LightWing AC4 Maintenance Manual

LightWing AC4

Maintenance Manual

LW-RL-Z-004 Rev.:1 Page 1

LightWing AC4 Maintenance Manual

Doc N° LW-RL-Z-004

LightWing AC4 Maintenance Manual


Intentionally left blank.

LightWing AC4

Maintenance Manual


Amendments

Issue Date Revised pages

Description

1st Edition 12-May-2014 all (1..123)

First Edition Original TC under ADxC-48-001-AMM

Rev.:0 23-Sep-2014 all (1..123) Transfer from ADxC-48-001-AMM 1stEdt. to LW-RL-Z-004 with detail rework

Rev.:1 19-Sep-2017 All (1…109) Detail Rework to V02

Rev. 1 15-Nov-2017 All (1…109 Detail Rework 912iS Sport

List of Service Bulletins

SB No Date Title Affected Serial no.’s

AD (EASA)


Table of Contents

Chapter Title ...................................................................................................... Page

01 Introduction ................................................................ 9

01-00 General ............................................................................................ 9

01-10 Coverage.......................................................................................... 9

01-20 Guidelines ........................................................................................ 9

01-30 Related Publications .......................................................................... 9

01-40 Addresses ...................................................................................... 10

02 How to Use the Manual ............................................. 11

02-00 General .......................................................................................... 11

02-10 Notes ............................................................................................. 11

03 General Description .................................................. 13

03-00 General .......................................................................................... 13

04 Limitations ............................................................... 16

04-00 General .......................................................................................... 16

04-10 Structural Limitations and Inspection Intervals ..................................... 16

04-20 Placards ......................................................................................... 16

04-30 Major Inspection .............................................................................. 17

04-30-10 Major inspection airframe .................................................................. 17

04-30-20 Major Inspection Engine Mount .......................................................... 17

04-40 Software ......................................................................................... 18

05 Inspection and Maintenance ....................................... 19

05-00 General .......................................................................................... 19

05-10 Time Limits and Inspection Program ................................................... 19

05-10-01 Component Time Limits .................................................................... 20

05-20 Scheduled Maintenance ................................................................... 21

05-20-01 Scheduled Inspection plan ................................................................ 21

05-20-02 Lubrication Chart ............................................................................. 37

05-20-03 Drain Holes ..................................................................................... 37

05-20-04 Maintenance Check Flight ................................................................. 40

05-50 Unscheduled Maintenance ................................................................ 46

05-50-01 Structure Dimension Check ............................................................... 46


06 Dimensions and Areas .............................................. 50

06-00 General .......................................................................................... 50

06-00-01 Coordinate System .......................................................................... 50

06-10 Main Data ....................................................................................... 50

06-10-01 External Dimensions ........................................................................ 50

06-10-02 Internal Dimensions ......................................................................... 50

06-10-03 Wing .............................................................................................. 50

06-10-04 Aileron ........................................................................................... 51

06-10-05 Flap ............................................................................................... 51

06-10-06 Horizontal Tail ................................................................................. 51

06-10-07 Elevator ......................................................................................... 51

06-10-08 Trim Tab ........................................................................................ 51

06-10-09 Flettner Tab .................................................................................... 52

06-10-10 Vertical Tail .................................................................................... 52

06-10-11 Rudder ........................................................................................... 53

06-10-12 Fuel System ................................................................................... 53

06-10-13 Landing Gear .................................................................................. 53

06-10-14 Engine and Propeller ....................................................................... 53

12 Servicing ................................................................. 54

12-10 Replenishing ................................................................................... 54

12-10-01 Replenishment of Brake Fluid............................................................ 54

20 Standard Practices Airframe ...................................... 55

20-00 General .......................................................................................... 55

20-10 Standard Practices Airframe ............................................................. 55

20-10-01 Standard Torque Values ................................................................... 55

20-10-02 Cable Tensions ............................................................................... 55

21 Environmental systems ............................................. 57

21-40 Cabin heating ................................................................................. 57

24 Electrical Power ....................................................... 58

25 Equipment/Furnishings ............................................. 61

25-10 Flight Compartment ......................................................................... 61

25-10-01 Seats ............................................................................................. 61


25-50 Baggage Compartment..................................................................... 63

27 Controls .................................................................. 65

27-10 Ailerons .......................................................................................... 65

27-20 Rudder ........................................................................................... 67

27-30 Elevator and Tab ............................................................................. 68

27-50 Flap System .................................................................................... 70

28 Fuel ........................................................................ 72

31 Indicating and Recording Systems .............................. 74

31-10 Instrument & Control Panels .............................................................. 74

32 Landing Gear ........................................................... 75

32-40 Wheels and Brakes .......................................................................... 77

34 Navigation ............................................................... 78

34-10 Flight Environment Data ................................................................... 78

34-10-01 Pitot/Static System ........................................................................... 78

51 Standard Practices and Structures – General ............... 81

51-30 Materials ........................................................................................ 81

52 Doors ...................................................................... 82

53 Fuselage ................................................................. 83

55 Stabilizers ................................................................ 89

55-10 Horizontal Stabilizer ......................................................................... 89

55-30 Vertical Stabilizer ............................................................................. 90


56 Windows ................................................................. 91

57 Wing ...................................................................... 92

61 Propeller ................................................................. 95

71 Power Plant ............................................................. 96

71-10 Cowling .......................................................................................... 96

71-20 Engine Mount ................................................................................. 98

71-30 Fire Seals ....................................................................................... 98

72 Engine .................................................................. 100

75 Air ........................................................................ 102

75-20 Cooling System ............................................................................. 102

76 Engine Controls ..................................................... 104

78 Exhaust ................................................................ 105

79 Oil ........................................................................ 106

91 Charts .................................................................. 107


List of Effective Pages

Page Date Page Date Page Date

1 Cover Rev. 1 24.07.17

2 thru 109


01 Introduction

01-00 General This Maintenance Manual provides educated maintenance staff information necessary for servicing, maintenance and repair of the LightWing AC4 CS-LSA Type aircraft. It contains a detailed description of systems including time limits for the particular components and instructions for the performance of inspections and maintenance. All service, maintenance, inspections, repairs and/or modifications shall be performed by adequate qualified/licensed personnel within approved maintenance organisations, certified according EASA Part-145/M or other applicable National Aviation Authority regulations. For all instruction necessary for major repairs and cases not covered in this manual, contact Light Wing AG. Instructions necessary for maintenance, repair and/or overhaul of vendor parts are not incorporated in this Maintenance Manual, appropriate documentation may be requested from the vendors or their representatives. For this contact addresses are provided in Chapter 01-40 Addresses of this manual. The instructions for installation, service, repair and maintenance of optional equipment shall be collected with this Manual.

01-10 Coverage This manual provides servicing and maintenance information for all LightWing AC4 aircraft. Maintenance actions that refer to a limited number of aircraft will be designated by serial numbers of the applicable aircraft.

01-20 Guidelines For general information on acceptable methods, techniques and practices, if not presented here, refer to FAA AC 43-13.

01-30 Related Publications Note If not stated otherwise use the latest revisions of documentation

presented in the following.

LightWing

AC4 Aircraft Flight Manual Doc. N°: LW-RL-Z-002


Rotax

Description

Operators's Manual OM-912 i

Installation Manual IM-912 i

Maintenance Manual Line MML-912 i

Maintenance Manuel Heavy MMH-912 i

Overhaul Manual OHM-912 i

Overhaul Manual, Appendix OHMA-912 i

Illustrated Parts Catalog IPC-912 i

Servive Bulletins, Service Instructions and Service Letters as issued

Neuform

C3 Series Operating and Maintenance Manual

DYNON AVIONICS

SkyView System Installation Guide SkyView Pilot’s User Guide

PowerFLARM

FTD-033 PowerFLARM Core installation manual

01-40 Addresses Contacts for service bulletins, general information and for ordering parts:

Firm Address

Light Wing AG Riedenmatt 1 6370 Stans Switzerland E-mail: [email protected]

Rotax Refer to Rotax Service network


02 How to Use the Manual

02-00 General The format and contents of this manual have been prepared in accordance with the GENERAL AVIATION MANUFACTURERS ASSOCIATION (GAMA) Specification No. 2. The contents of this manual are organized in three levels:

Group

System/Chapter

Subsystem (if needed)

Group

Groups used in this manual are:

Group Chapters Definition / Remark

General 01 & 02 General information

Aircraft 03 thru 20 Complete operational unit, limitations

Airframe systems 24 thru 34 All airframe systems except power plant

Structures 51 thru 57 All aircraft main structures

Propeller 61 Propeller information

Power Plant 71 thru 80 Power plant information

Miscellaneous 91 Charts

Supplementary information To be collected in Appendix

Forms, Advanced maintenance instructions, Service bulletins etc.

System/Chapter

Systems are arranged numerically per GAMA Specification 2 (ATA 100) recommended number assignment. The first two numbers indicate the chapter or system; the second two indicate the sub-system or section (for example Chapter 02-10). When a subsystem is further divided into units, a third element is added to the number sequence, e.g. 53-20-01 The table of content lists only those chapter numbers which are used in this supplement.

02-10 Notes Notes and safety notes in this handbook are marked by the words Note, Important, Caution, Warning or Danger in the left margin column. The latter


three words are emphasized by a safety sign. The text of the note or safety note is printed in bold. See the following examples:

Danger Represents a dangerous situation. The non-observation of this safety note will result in death or serious injuries.

Warning Represents a dangerous situation. The non-observation of this safety note may result in death or injuries.

Caution Represents a danger to equipment. The non-observation of this safety note will result in destruction of equipment. This safety note does not exclude a possible danger for persons.

Important Represents an important hint.

Note Represents a remarkable hint.


03 General Description

03-00 General The LightWing AC4 aircraft is a

Conventional high strutted wing configuration;

Conventional strutted tail;

Single Rotax piston tractor engine with fixed pitch propeller;

2 seat side by side;

Fixed tricycle landing gear with steerable nose wheel

airplane.

Figure 1: AC4 isometric view


Figure 2: AC4 side view

Figure 3: AC4 top view


Figure 4: AC4 front view


04 Limitations

Rev. No Description EASA Approval Number and date

1st Edition Initial TC EASA.A.588 17.6.14

04-00 General At time of print only a white top surface for the fabric covered parts is approved. If darker colours shall be used for striping or overall contact Light Wing AG for approval.

04-10 Structural Limitations and Inspection Intervals The airframe of the Lightwing AC4 is limited to 6000h, the engine mount to 4000h. In addition, the airframe must undergo a major airframe inspection according to 04-30 at 3000h/10year (whichever comes first) intervals for the airframe and at 2000h/10year (whichever comes first) intervals for the engine. The wing, stabilizer and movable control surface cover is limited to 5years of service live.

Note This limit is initially defined, before exchange of the fabric cover contact Light Wing AG for potential revised limits

Note Whenever the wing or stabilizer covers are removed the according major inspection shall be performed. This avoids removing the cover exclusively for this purpose.

04-20 Placards For Markings and Placards refer to LightWing AC4 Aircraft Flight Manual, Section 2, Document N°: LW-RL-Z-002.


04-30 Major Inspection

04-30-10 Major inspection airframe

The major airframe inspection program is not defined at time of print. Upon reaching this airframe life limit contact Light Wing AG. Critical components are: Main beam 1000-00003 Cross beam 1000-00005 Horizontal stabilizer interface 1000-00063/64/65/66/67 Cross beam to fuselage interface 1000-00059 /60/61/62 Verbindung Dachstrebe vorn 1210-00001 Verbindung Dachstrebe hinten 1220-00001 Kabinenabstützung 1400-0001 Horizontal stabilizer front tube 1500-00003/4 Vertical stabilizer front tube 1600-00003 Wing front spar 2111-00001 / 2211-00001 Wing rear spar 2121-00001 / 2221-00001 Stütze hinten 1007-00001 Struts adjacent to Engine mount 4100-00051

04-30-20 Major Inspection Engine Mount

Relevent P/N Engine mount 4100-00051 The inspection is best performed with the engine removed, which however is not mandatory. The inspection is required to be performed each 2000h, but recommended to be performed whenever the engine is removed from the airframe.

Major Inspection engine mount 2000h

Preparatory Activities

Remove engine (recommended) ○

Clean the engine mount thoroughly ○

Inspection

Visually inspect all engine mount struts for straightness using appropriate straight ruler lengths.

○

Check torque of all attachment bolts, ref 20-10-02. ○

At locations where bolt torque is below the specified values: remove bolt and inspect for sights of wear or overload. Discharge the respective (stop) nuts. If a bent bolt is found the engine mount must be removed from the airframe to further inspect the respective bearings on airframe and engine mount side. Report such condition to Light Wing AG.

○


Major Inspection engine mount 2000h

Visual inspect entire top coat paint of engine mount for scrathces and cracks. ○

Where top coat cracks are found remove top coat in the affected area and min 10mm further.

○

Perform dye penetrant check at all welding nodes and all identified top coat crack locations.

○

In case of doubt remove top coat at entire node. ○

If cracks are found report to Light Wing AG before proceeding ○

Finish

Refinish top coat at weld nodes as required. Touch up top coat at all other identified scatches

○

Reinstall engine (if removed) ○

Make appropriate airplane log book entry for release to furhter service ○

04-40 Software Only Software delivered with the airplane, or as mandated by resperctive Service Bulletins are approved to be used in the AC4. This adresses:

Function Unit Software revison (approved at time of print)

Fuel metering and ignition timing

ECU of Rotax 912iS/iSC 130

Engine indication EMU 912iS Evo EMUevo AC41

MFD configuration Skyview System 15.0.2


05 Inspection and Maintenance

05-00 General This chapter contains charts, tables and checklists for time limits, scheduled and unscheduled maintenance, to enable licensed personnel to carry out correct inspections on the LightWing AC4 aircraft. The periodic inspections and checks described and the related intervals are minimum required for maintaining the aircraft in airworthy condition. Specific operation and specific operation environments might require shortening the intervals. The regulating airworthiness authority must approve any increase of interval time.

Important The regulatory authority might require specific (additional) inspection or calibration items as well as replacement/overhaul intervals not described in this manual. It is the responsibility of the operator and maintenance personnel to adhere to national regulations.

05-10 Time Limits and Inspection Program The LightWing AC4 aircraft scheduled inspection and maintenance program comprises:

Non repetitive aircraft inspection at 25 hours after delivery of the aircraft or installation of a new, rebuilt or overhauled engine, including a break-in inspection and maintenance of the power plant corresponding to the 100 hours/annual inspection.

Recommended repetitive 50 hour inspection mainly covering power plant, and fuel system (firewall forward).

Mandatory repetitive 100 hour inspection or annual inspection, whichever comes first, which includes the coverage of the 50 hour inspection plus the inspection of the aircraft controls, structure landing gear and the fuel system aft of firewall.

Unless stated otherwise the inspection methods follow standard practice and are mainly visual. However specific attention shall be paid to the elements listed in section 04-30-10. In case of doubt consider dye penetrant inspections at the welding connections and highly stressed areas as indicated in the inspection list.


05-10-01 Component Time Limits

Time between Overhaul

Component Interval

Propeller Neuform 1000 h

Rotax 912i Engine

2000 h (refer to latest ROTAX documentation applicable to the actual SN of the engine)

Time Between Replacement

Component Interval

ELT Batteries 6 years

Dynon SkyView Batteries Depending on annual test result

Engine mount 4000h

Airframe elements as listed in section

04-30-10

6000h


05-20 Scheduled Maintenance

05-20-01 Scheduled Inspection plan

Scheduled Inspection Report

Make

LightWing

Model

AC4

Serial Number

Registration

Owner Date

Type of Inspection Airframe time (logbook)

Scheduled Inspection 50 h 100 h/ annual

as specified

Preparatory Activities

Review of aircraft logbook ○ ○ ○1

Check that all applicable Service Bulletins are complied with. ○ ○ ○1

Check that all applicable Airworthiness Directives are complied with. ○ ○ ○1

Carry out a Daily Inspection according the flight manual. ○ ○ ○1

Start up engine in accordance with AFM ○ ○ ○1

Check all engine related instrumentation and fuel quantity. ○ ○ ○1

Check voltage indication. ○ ○ ○1

Check function of exterior lights as installed. ○ ○ ○1

Shut down in accordance with AFM. ○ ○ ○1

Remove top and bottom cowling ○ ○ ○1

Clean and inspect cowling structure for cracks, dent and other damage, security of cowling fasteners.

○ ○ ○1

Check hinges and locking mechanism of access hatch for proper operation.

○ ○ ○1

Inspect cowling internal coating for deterioration and signs of overheat.

○ ○ ○1

Inspect seal to coolant radiator for signs of wear. ○ ○ ○1

Remove top empennage panel, tail cone and control stick sleeve. ○

1 First 25 hours of operation for new or overhauled engine



as specified

Inspect top empennage panel and tail cone for delamination, discoloration, cracks and damage, and condition of paint.

○

Check control stick sleeve for condition. ○ ○

Remove bottom empennage panel, middle console, baggage compartment panels, seats, and wing root covers.

○

Inspect bottom empennage panels for delamination, discoloration, cracks and damage, and condition of paint.

○

Inspect middle console and baggage compartment panels for cracks and damage.

○

Engine Installation

Take precautions against accidental starting or firing of the engine by removing ignition leads.

○ ○ ○1

Perform engine inspection, oil change etc. according to ROTAX 912 i Series Line Maintenance and Operators Manual, Chapter 05-20-00. Observe the following when performing an engine test run:

○ ○ ○1

Confirm NO electrical ground connection between regulator housings as well as from firewall (ground reference) to the starter relays housing (resistance >20MΩ)

○ ○ ○1

Inspect hose from inlet manifold to fuel pressure regulator for leaks or cracks

○ ○ ○1

Oil System

Check oil thermostat for proper attachment. Inspect for leakage ○ ○ ○1

Inspect oil breather line for proper routing, internal accumulation of oil/water emulation, and clogging. Clean as required.

○ ○ ○1

Inspect oil cooler for leaks and proper installation. ○ ○ ○1

Inspect cooling fins for dirt and damage. ○ ○ ○1

Coolant System

Check coolant thermostat for proper attachment. Inspect for leakage ○ ○ ○1

Inspect coolant radiator for leaks and proper installation. ○ ○ ○1

Inspect cooling fins for dirt and damage ○ ○ ○1

Inspect engine cooling cap for cracks, deterioration and breakage. ○ ○ ○1

Inspect cooling tank attachment grommets, and replace if needed ○ ○ ○1

Fuel System

Inspect electric dual fuel pump for leakage and attachment. Inspect electric connections for security and corrosion.

○

Replace fine filter element in engine bay ○



as specified

Clean fuel filter next to shut-off valve and inspect for foreign particles.

○

Cabin Heat System (if installed)

Inspect hoses for attachment, leaks and wear. ○ ○

Inspect air scoop at radiator for cleanness ○ ○

Inspect save closure of cabin air valves ○ ○

Inspect heat shroud on exhaust for cracks ○ ○

Remove heat shround for inspection of underlying plenum chamber ○ ○ ○1

Exhaust System

Inspect flanges and stack-pipes. (Exhaust stack attachment studs & nuts are prone to loss of torque due to vibration and thermal expansion.)

○ ○ ○1

Check EGT sensors for proper installation ○ ○ ○1

Inspect muffler for cracks, leakage and security of attachment. ○ ○ ○1

Check ball joint for freedom of movement. Disassemble and clean ball joint as required and reassemble with

heat resistive lubrication (copper paste). Refer to Section 05-20-02

Lubrication Chart.

○ ○ ○1

Check condition of springs and presence safety wire. ○ ○ ○1

Specifically inspect the areas around spring attachment hooks welded to the respective piping. Those areas are especially prone to fatigue cracks. In case of doubt remove the exhaust system and perform dye-penertrant inspection

○ ○ ○1

Remove end pipe and perform internal inspection (Visual) ○ ○ ○1

Remove end pipe and perform internal inspection (boroscope) 500h/ 5 Years

Air Induction

Inspect MAT/MAP sensor for foreign particles. Check for proper installation.

○ ○ ○1

Inspect air filter element for foreign particles. Install new air filter element on condition.

○ ○ ○1




as specified

Engine Controls

Check throttle control for proper attachment, full travel, freedom and smoothness of movement.

○ ○ ○1

Clean and lubricate Bowden cable. Refer to Section 05-20-02

Lubrication Chart. 500h/

5 Years

Inspect all wiring connected to the engine, regulators and accessories for attachment, leads, chafing etc.

○ ○ ○1

Inspect all firewall-mounted items for security of attachment. ○ ○ ○1

Inspect fuel pressure sensor mounting for leaks. ○ ○ ○1

Check battery for general condition, recharge as required. Apply a thin layer of MS4 grease to the battery connections.

○ ○ ○1

Inspect battery cables for signs of corrosion or cracks. Check cable routing and attachment.

○ ○ ○1

Inspect battery isolation provisions. ○ ○ ○1

Inspect regulator units for attachment and damage. ○ ○ ○1

Engine Mount

Inspect engine mount structure for cracks and damage. Pay specific attention to weld connections. In case of doubt consider dye penetrant inspection.

○ ○

Perform Major engine mount inspection per 05-30-20 2000h

Inspect engine mount attaching bolts at the firewall and the main beam connection. Check torque on all attachment points, re-torque as required per 20-10-02.

○ ○ ○1

Inspect shock mount rubber elements (vibration isolators) for condition.

○ ○ ○1

Check engine to shock mount attaching bolts, castle nuts and cotter pins.

○ ○ ○1

Propeller

Remove spinner. ○ ○

Inspect spinner for cracks and fractures ○ ○

The propeller must have a major overhaul by the manufacturer. 1000h

Inspect propeller mounting for security of installation. ○ ○




as specified

Inspect mounting bolts. Re-torque mounting bolts according to chapter 61

○ ○ ○1

Inspect propeller blades for cracks, dents, nicks, scratches, erosion or other damage.

○ ○

Inspect propeller blade mounting for wear and play (no play allowed at blade tip in any direction). A little angular play in the gear is normal (1-2 mm at blade tip). To make sure that no additional play is present in the blade retention manually counteract play detection force at the spinner or another blade to eliminate the gear influence.

○ ○

Measure actual propeller blade angles (gaugeable secant angle). ○ ○2

Reinstall spinner. Check for proper attachment ○ ○

Finish

Inspect entire engine compartment for foreign objects, loose connections of earlier work, correct application of safety wire and cotter pins at all locations where work was executed.

○ ○

Structure

Fuselage

Check main beam for condition and security. ○

Check all main beam mountings for condition and security. Inspect for deformation. Check rivets and bolt connections for condition.

○

Inspect main beam in area above cross beam for signs of cracks, check main beam to cross beam mounting for loose rivets or bolts. In case bolt connections show signs of wear, remove bolts and sleeves and check for roundness and tolerance of holes and sleeves. Contact Light Wing AG for options to mount oversize sleeves if needed.

○

Check cross beam for condition and security. ○

Check cross beam mounted brackets for proper (security of) attachment.

○


2 Anytime unusual vibrations are detected or a gaugable blade angle outside of specificed

tolerance is found, the propeller needs adjustment according chapter 61.



as specified

Inspect front and rear cross beam struts ("base brace"; V struts facing FWD and aft from cross beam to main beam) for deformation and cracks. Check rivets for condition. No gaps between tube and rod ends allowed.

○

Check base brace mounting flange to main beam for condition. Inspect for deformation and cracks. Check rivets for condition.

○

Inspect base brace for deformation and cracks. Check rivets for condition.

○

Inspect cabin bearing structure (connecting rods in roof area) for deformation and cracks. Check rivets for condition. No gaps between tube and rod ends allowed.

○

Inspect cabin support (vertical struts aft of pilots and center strut in front of pilots) for deformation and cracks. Check rivets for condition. No gaps between tube and rod ends allowed.

○

Inspect front and rear cabin roof welded steel structures for cracks. In case of doubt consider dye penetrant inspection.

○

Inspect rear cabin struts (V strut roof to tail) for deformation and cracks. Check rivets for condition. No gaps between tube and rod ends allowed.

○

Inspect intermediate elevator bellcrank / rear roof strut support for cracks, loose rivets and signs of deformation.

○

Inspect cabin composite frame for delamination, discoloration, cracks and damage, and condition of paint.

○

Inspect door structure for delamination, discoloration, cracks and damage, and condition of paint.

○

Check door hinges for condition. ○

Check door locking mechanism for proper operation. ○

Lubricate Locking pins as per Section 05-20-02 Lubrication

Chart. ○

Lubricate Locking mechanism as per Section 05-20-02

Lubrication Chart. 500h/

5 years

Inspect belly panel for delamination, discoloration, cracks and damage, and condition of paint.

○

Inspect centre wing roof panel for delamination, discoloration, cracks and damage, and condition of paint.

○

Check windshield structure frame for condition. ○

Inspect windshield and windows for deterioration, nicks, scratches, cracks and crazing.

○



as specified

Check instrument panel for condition and proper attachment. ○

Seats and Restraint System

Check seat support structure for condition ○

Check seat adjustment, lubricate per Section 05-20-02

Lubrication Chart. ○

Check seat upholstery and cushions for condition and attachment ○

Check seat belt condition and attachment for wear. ○

Surface

Inspect skin for delamination, discoloration, cracks and damage, and condition of paint.

○ ○

Inspect drain holes for obstructions. ○ ○

Wing Attachment

Check main bolts for security. ○

Shake wings to determine play of bolt connections. ○ ○

Inspect struts and secondary struts for damage and deformation. ○

Inspect struts to wing and struts to fuselage brackets for cracks and deformation.

○

Check bolt connections ○

Check pin and locking ring connections of secondary struts ○

Wing

Check fabric and seams for general condition. Inspect for cracks, damage and bumps.

○

Check root rib lace fastening for condition. ○

Check condition of zip fastener ○

Check wing tube structure for cracks and damage. ○

Check bolt connections of internal wing structure. ○

Check attachment, condition and tension (check by tensionmeter min. 500 N) of bracing cables.

○

Check position and condition of leading edge contour shape. Inspect for breakage.

○

Check wing twistas per Chapter 57. 500h/ 5 years

Inspect wing internal for accumulation of water and/or moisture. ○

Check drain holes in fabric (every second field in front rear spar ○



as specified

Check all internal wing batten holders on front and rear spar, as well as wing batten distance holders for cracks.

○

Horizontal Stabilizer Attachment

Check condition of mounting flanges. ○

Check rivets for condition. ○

Check condition of clamping plates and half clamps. ○

Check bolt connections for security. ○

Horizontal Stabilizers

Check condition of tube structure. ○

Check attachment (half clamps, clamping plates and bolt connections) for condition and security.

○

Check condition of profile foam ribs and security of attachments. ○


○

Check condition and security of root fastening (Do not open fastening. It cannot be closed without reducing the fabric tension).

○

Vertical Stabilizer Attachment

Check condition of tube lead through sheets. ○

Check condition and security of locking rings. ○

Check rivets for condition. ○

Check struts for condition and security. ○

Check locking rings installed. ○

Vertical Stabilizer


Check saddle pieces and bolt connections for condition and security. ○

Check profile foam ribs and attachment. ○


○

Check condition and security of root fastening (Do not open fastening. It cannot be closed without reducing the fabric tension).

○

Stabilizer Struts

Inspect for general condition (straightness), play in connection, tightness of attaching elements, presence of safety rings. Light play (less than 0.1mm can be eliminated by Loctite, larger play is reason to suspect overload, parts must be replaced)

○



as specified

Control Surface Hinges

Lubricate hinges as per Section 05-20-02 Lubrication Chart. ○

Check saddle pieces of hinges for condition and safety of attachment. (Wing hinges have saddle pieces only on the control surface side.)

○

Check hinges for freedom of movement and safety of attachment. ○ ○

Check locking rings are installed. ○ ○

Control Surface



○

Check condition and security of hook-and-loop fasteners on the hinge line.

○

Flap Actuation System

Check for condition and proper, smooth operation through full travel. Check for free movement.

○ ○

Lubricate bearings as required. Refer to Section 05-20-02

Lubrication Chart. ○

Check actuator for proper attachment and operation ○

Check push rods for condition and security. No gap to the rod ends. Check rivets for security of attachment.

○

Check flap actuation lever for condition. Inspect for deformations. ○

Check deflections. Refer to Section 06-10-05 Flap for nominal values. Full up (0°), actual LH……….RH…… Intermediate (10°), actual LH……….RH…… Full down (24°), actual LH……….RH…... Perform Flap Rigging as per Chapter 27, if values are out of tolerances.

○

Aileron Control


○ ○

Check torque tube for condition, security, and operation through full travel.

○

Check brackets for condition and security of attachment to the main beam.

○



as specified

Check condition and security of travel stops. ○

Check condition, security and tension (100-200 N) of control cables. ○

Check condition, free movement and security of pulleys. ○

Check central bellcrank for condition. ○

Check push rods inside the wing for condition and security. ○

Check bellcranks inside the wing for condition and security. ○

Check aileron actuation lever for condition. Inspect for deformations. ○

Check deflections. Refer to Section 06-10-04 Aileron for nominal values. Up (22°) actual L……....R…………. down (20°) actual L….......R…...…….. Perform Aileron Rigging as per Chapter 27, if Values are out of tolerances.

○

Elevator Control and Trim System


○ ○

Check elevator control rods for condition, security of attachment, and operation through full travel. No gap to the rod ends. Check rivets for security of attachment.

○

Check bellcranks and brackets for condition and security of attachment.

○

Inspect travel stops at the rocker type bellcrank bracket for deformations.

○

Check deflections. Refer to Section 06-10-07Elevator for nominal values. Up (30°), actual …….. down (-30°), actual …….. Perform Elevator Rigging as per Chapter 27, if values are out of tolerances.

○

Elevator Trim Tab System

Check for condition, security, free movement and operation. ○ ○

Check switch positions in relation to the travel direction. ○

Check elevator trim indication to match actual position. ○

Check deflections with elevator neutral. Refer to Section 06-10-08Trim Tab for nominal values.Up (5°), actual …….. down (-27°), actual …….. Perform Trim Tab Rigging as per Chapter 27, if Values are out of tolerances.

○



as specified

Elevator Flettner Tab System

Check for condition, security, free movement and operation. ○ ○

Check deflections. Refer to Section 06-10-09 Flettner Tab for nominal values. Elevator Up (tab at -26°), actual …….. Elevator neutral (tab at -12°) actual …….. Elevator down (tab at +7°), actual …….. Perform Flettner Tab Rigging as per Chapter 27, if Values are out of tolerances.

○

Rudder Control System


○ ○

Check rudder mounted actuation bracket for security. Inspect for cracks.

○

Check rudder travel stops for signs of overload. ○

Inspect cables for wear, security, condition and operation through full travel.

○

Check Bowden cable counter brackets for condition and secure fastening of adjustment.

○

Check cable tension (100 – 200 N) ○

Check rudder pedals for general condition and proper attachment. Inspect for cracks.

○

Check deflections. Refer to Section 06-10-11 Rudder for nominal values. LEFT (25°), actual …….. RIGHT (25°), actual ……... Perform Rudder Rigging as per Chapter 27, if values are out of tolerances.

○

Fuel System (excluding firewall forward)

Rotate engine key to "START POWER", to energize fuel pump (do not rotate key to "START". Open shut-off valve and check all fuel system connections downstream of the electric fuel pump for leaks.

○

Check fuel pressure indication reads 3 bar (START POWER ON). If value is below 3 bar, inspect fuel lines for clogging and kinks, and replace fuel filter. If value is above limit inspect return line for clogging and kinks

○



as specified

Check shut-off valve function by closing while fuel pumps are running (START POWER ON). Check fuel pressure indication drop, reopen shut off valve and check fuel pressure regain. Switch START POWER OFF.

○

Fuel Tank

Check fuel tank attachment. ○

Inspect fuel tank for evidence of leakage and/or damage. ○

Check fuel cap for condition and proper operation. ○

Drain fuel at fuel tank bottom. ○

Remove drain valve and inspect for sediment 200h/ 2 Years

Open fuel tank top plate and remove internal slosh panel, inspect for cleaniness

500h/ 5 years

Fuel Lines, Hoses and Elements

Inspect fuel lines and hoses for damage, leakage and proper routing.

○

Inspect vent system for obstructions. Check for free airflow. ○

Visually inspect fuel quantity sight gauge tube housing for damage and leakage.

○ ○

Verify fuel quantity sight gauge lighting system operational ○ ○

Visually inspect fuel shut off valve for leakage. ○ ○

When refilling system (aircraft in level attitude): check indication and low level warning operation. Indicator may not start indication of usable fuel when total fuel quantity in system is below published unusable quantity of 4 Liter per side. Low level warning must trigger at total (steady) quantity of 6 Liter per side. Cross check fuel quantity sight gauge indication.

500h/

5 years

Instruments

Check instruments for condition, security and proper markings. (Instrument dials or markings may not be excessively faded out due to sunlight.)

○

Check instrument lines and wiring for condition, proper routing, and security.

○

Check Pitot-static system for condition, proper installation and security.

○

Check Pitot-static system moisture traps, clean as required. ○



as specified

Perform Pitot-static system leak test: Pitot: pressurize to 240km/hIAS, allowable drop 20km/h/min Static: evacuate to 10000ft, allowable drop 100ft/min. Note: allow vertical speed indicator (if installed) to stabilize before taking measurement. Most likely points of leakage are the instruments themselves and hose connections.

○

Avionics

Inspect avionics units and related antennas for security of installation and condition.

○

Inspect cables and connectors for attachment. ○

Inspect microphone and jacks for cleanliness security and evidence of damage.

○

Inspect ELT and AHARS mounting on main beam. ○

Conduct Magnetic Heading Calibration of AHARS as per DYNON AVIONICS SkyView System Installation Guide latest Revision.

○1

Follow the Instructions of Continued Airworthiness as per DYNON AVIONICS SkyView System Installation Guide latest Revision.

○

If installed check ELT for condition and exp. Date of battery, replace battery if needed.

○

Perform radio and transponder check. ○1

Perform PowerFLARM firmware and obstacle database update as required. Consult Light Wing AG for latest approved release. Perform range analysis as described in PowerFlarm manual.

○

Magnetic Compass

Check magnetic compass for security and cleanliness. Inspect for leakage and evidence of damage.

○ ○

Perform magnetic compass compensation. ○2

Electrical System (excluding firewall forward)

Inspect electric wiring for proper routing chafing loose or broken wires/connectors, check attachment.

○

Inspect circuit breakers and switches for operation and security. ○

Check navigation and strobe light for condition and proper installation.

○

1 As mandated by local regulations

2 According to country-specific requirements



as specified

Landing Gear & Brakes

Main Landing Gear Attachment

Check bayonet bolts for proper attachment of security bolts. ○

Inspect bearing roller for fretting, wear and damage. ○

Check rubber buffer for condition and proper attachment. Inspect for cracks.

○

Main Landing Gear

Check main landing gear and fairing for general condition. ○

Inspect main gear springs for cracks and deformation. ○

Check axle mounting for condition and proper attachment. ○

Check pivot axles for security and presence of cotter pin. ○

Nose Gear

Check nose gear for condition and attachment. ○ ○

Inspect nose gear fork for deformation, cracks in welding seams or due to material fatigue or stress.

○

Check nose gear elastomere for condition. ○ ○

Inspect nose gear steering rod attachment. Lubricate rod ends as

per Section 05-20-02 Lubrication Chart. ○

Wheels and Tires

Check rims for condition. ○ ○

Inspect tires for cracks, cuts and condition. ○ ○

Inspect slip marks for proper alignment. ○ ○

Check nose and main wheel tire pressure nose: 2.7 bar; main 3.0 bar

○ ○

Check wheel bearing for play, replace if needed and re-install according Chapter 32-42.

○

Brakes

Inspect control stick mounted brake cylinder for leakage, damage and attachment.

○ ○

Inspect brake disc and linings for wear and cracks, replace as required. For limits refer to Chapter 32-44.

○ ○

Inspect wheel brake cylinders for damage wear, leakage and cleanliness.

○ ○



as specified

Check brake lines and hoses for proper routing and attachment. ○ ○

Check brake filling state according AFM, refill as required. ○

Check park brake action. ○ ○

Replace brake system fluid as per Chapter 12-10-01 Replenishment of Brake Fluid

200h/

2 years

Placards (refer to pilot’s operating handbook)

Placards and Decals: Check presence, legibility and security. Consult AFM for required placards exterior and interior.

○

Finish

Inspect all aircraft compartments for foreign objects, tools etc. ○ ○ ○1

Reinstall (as applicable): middle console baggage compartment panels seats top and bottom cowling top and bottom empennage panels tail cone

Note: If specific work involved opening/closing of oil, coolant or fuel system related hose connections, it is advised to execute a short ground run without cowling to check for leaks.

○ ○ ○2

Check seat belt routing ○ ○ ○1

Check control system operation. ○ ○ ○1

Reattach ignition leads to spark plugs. ○ ○ ○1

Ground Run

Perform engine ground run (without upper cowling) according to ROTAX 912 i Series Line Maintenance and Operators Manuals. Observe the following when performing an engine test run:

○ ○ ○1

Check general conditions and powerplant start behavior ○ ○ ○1

Lane A & B check (refer to ROTAX 912 i Series Operators Manual). ○ ○ ○1

Check pressures, temperatures, acceleration performance ○ ○ ○1

Perform Full Throttle Test Check. ○ ○ ○1

Check brakes at full throttle ○ ○ ○1

Check Idle RPM (refer to ROTAX 912 i Series Operators Manual). ○ ○ ○1





as specified

Fuel pressure within limit over complete RPM range both pumps individual and in combination.

○ ○ ○1

Check battery and power generation. ○ ○ ○1

Install upper cowling ○ ○ ○1

Perform maintenance check flight according to 05-20-04 Maintenance Check Flight

○1 ○1

Make appropriate aircraft and engine logbook entries for scheduled powerplant service.

○ ○ ○1

Ensure all Maintenance Record log-book entry’s required are complied with before the aircraft return to service.

○ ○ ○1

File all documents e.g. inspection report, ground run report Forms and tags in aircraft history file.

○ ○ ○1

Clean exterior of aircraft as required, pay attention to any unusual surface condition.

○ ○ ○

Vacuum clean aircraft interior as required. ○ ○ ○

Ensure the entire aircraft is clean. ○ ○ ○

1 After new adjustment from elements of the control systems, retension of the fabric and all

repairs


05-20-02 Lubrication Chart

Three types of lubricants are used which are

"oil", meaning any general purpose mineral oil according to MIL-PRF-7870 or similar

"grease" meaning any water free general-purpose grease according to MIL-PRF-81322 or similar.

"copper paste" meaning any high temperature copper anti-seize according to MIL-PRF-907E or similar

Interval Item Lubricant

100 h/ annual

All cable timble endings and cable rod ends MIL-PRF-7870

Control surface hinges, rod end external MIL-PRF-7870 after disassembly: MIL-PRF-81322

Door pins MIL-PRF-81322

Nose gear steering rod ends

Seat tracks

Exhaust ball joints MIL-PRF-907E

500 h/ 5 years

Throttle Bowden cable housing and core MIL-PRF-7870

Door locking mechanism MIL-PRF-7870 after disassembly: MIL-PRF-81322

All internal control system bellcranks including flap actuation system bearings,

MIL-PRF-81322

Cable pulleys

Nose gear pivot axis

The AC 4 features a number of dry bearings which in essence do not need any lubrication, if those bearings are questionable in their status just clean and inspect. In case the bearing shows signs of wear they need to be replaced. However, a thin grease layer does not hurt, therefore theses bearings are listed in the 500h schedule. Those bearings are the door hinges and rudder pedal hinges and all internal control system bellcrank bearing. The wheel bearings are life time lubricated - in case of questionable status they need to be replaced.

05-20-03 Drain Holes

Drain holse are located in the composite cowling, belly panel and lower empennage panel as well as in the lower fabric surfece of wing and horizontal stabilizer. Drain holes must be inspected regular for obstruction.


Figure 5 Drain holes cowling area

Figure 6 Drain holes belly panel area (view from RH side)


Figure 7 Drain hole tail

Figure 8 Drain holes horizontal stabilizer fabric

Figure 9 Drain holes wing fabric (infront rear spar)


05-20-04 Maintenance Check Flight

The maintenance check flight is intended to check whether the aircraft can be released for service. Reasons for performing a maintenance check flight can be different. Examples include restoring to operation after the aircraft has been stored for a long period, with yearly maintenance, or aircraft modifications. The maintenance check flight should be performed by a pilot who has sufficient experience with general aviation aircraft and is sufficiently familiarized with the type. Prior to starting the maintenance check flight the ground tests have to be completed satisfactorily and the aircraft has to be released by authorized personnel for the maintenance check flight. The pilot should read the relevant chapters in the airplane flight manual prior to executing the maintenance check flight.

Important The pilot should be aware of the fact that due to maintenance/modifications systems may have malfunctions which have not been discovered in prior inspections.

The Maintenance check flight is to be conducted using the Maintenance Check Flight Form (refer to Chapter 91 Charts). On this form all the items to be checked are indicated. For all the relevant items a short description is given here. The maintenance check flight is not intended to fly a complete evaluation program but covers all the relevant items satisfactorily to be able to decide whether or not the aircraft can be released for further service. Start with filling in the items on the first four rows. These parameters reflect the general aircraft data, meteorological and flight conditions.

General

The maintenance check flight consists of three parts: performance tests, system tests, and flight handling tests. However, some of the system tests are best to be done on with the engine running on ground. For the flight test, use airspace that is sufficiently clear of other traffic so the pilot is not distracted from executing the tests. For flight handling, the flight altitude should be sufficient for executing the specific tests and should include a sufficiently large safety margin. If the weather does not permit this, postpone the test but do not omit it from the program. If during the test any indication shows a possible malfunctioning, do not continue the test but land as soon as practical and have the aircraft inspected. After the maintenance check flight has been completed and the form has completely been filled in, the authorized inspector must indicate in the top row of the corner whether the aircraft can be released for further service. There are three possible conclusions:

Released for further service

Released for further service after the comments/complaints found in the flight have been addressed, no new flight necessary

Not released for further service, comments and complaints found in the test have to be addressed, an additional flight is required

Finally, the inspector has to date and sign the form.


Performance Tests

The goal of the performance tests is to have a spot check of three relevant flight conditions in the envelope. Climb, cruise, and full throttle level flight are checked. Both flight performance and engine performance are monitored.

Climb

Fly the aircraft at a speed between 105 and 115 km/h IAS using a full throttle and flaps retraced. Fly this as stationary as possible while monitoring the flight and engine instruments. Note down the relevant values on the form. Do not fly this test for a too short period. Allow the engine to stabilize the oil temperature. Compare this data with the data displayed in the airplane flight manual. The corrected flight data should correlate with the data in the airplane flight manual. Correction procedures are given in the flight manual.

Cruise

Fly the aircraft at a typical cruise speed of 150 to 160 km/h IAS. Monitor the indicated parameters. Allow the situation to stabilize before writing down the data. Compare this data with the data displayed in the airplane flight manual. The corrected flight data should correlate with the data in the airplane flight manual.

Full Throttle Level Flight

Fly the aircraft at full throttle. Build up speed in moderately descending flight up to the expected maximum cruise speed. Level off and allow the aircraft to stabilize for some time. Reaching the maximum level flight speed can take several minutes. Fly this manoeuvre as stationary as possible. Write down the requested parameters. Compare this data with the data displayed in the airplane flight manual. The corrected flight data should correlate with the data in the airplane flight manual.

System Tests

The system tests are meant for checking the systems of the aircraft. The systems are subdivided into 7 groups. For each group the relevant systems are indicated on the form. Check their functionality and indication where relevant. On the form indicate an acceptable functionality with a “+”. A functionality which is not acceptable should be indicated with a “-“. Use the reverse of the form to write down possible comments or complaints. Try to be as accurate as possible in writing the comments/complaints. This will allow maintenance personnel to handle this adequately.

Flight Controls

Elevator/Aileron/Rudder/Flap Check the elevator/aileron/rudder controls for smooth operation and forces as expected. Do not apply full or abrupt control inputs at speeds above 176km/h IAS. While increasing speed do not allow the speed to increase above VNE (210 km/h IAS), keep engine RPM within limits. While decreasing


speed do not stall the aircraft. Check controls with all possible flap settings. The maximum speed with flaps intermediate and full flaps is 165 km/h IAS.

Longitudinal Trim Operate the trim through the full range. It should be possible to trim the aircraft in a speed range above 90km/h IAS at Full throttle and flap up as well as 100km/h IAS at 3000RPM and flap up. A larger trim range is amongst other depending on the cg position. Check both full forward and full aft trim. Stick forces change significant with trim setting. Fly the trim test for nose up at low, for nose town at high speeds. Note that full nose down trim with flaps extended would result in speeds above VF and, depending on CG also above VNE for clean configuration

Lateral and Directional Trim The aircraft should be adequately trimmed lateral and directional at a cruise speed of 125-150 km/h IAS.

Flap Control Check for proper functioning of the flap controls. This may be done on the ground or in flight at an airspeed of less than VF (IAS < 165 km/h). Select intermediate flap position then full flap position, verifying visually that the flaps have deployed and retracted correctly.

Engine Controls

Throttle Check the smooth operation of the throttle over its complete range. The engine should give a direct response.

Engine Electric Control Switches Check the operation of the engine key switch before takeoff according to the AFM. Check operation of main and auxiliary fuel pump before takeoff according to the AFM.

Other Controls

Door Locks Door locks are not tested in flight as such, however throughout the engine RPM range the lock handles should be observed to ensure the lock does not open due to vibrations.

Brake and Park Brake Check the function of the brakes during taxi. Perform stops using the brake to verify smooth and symmetric operation of the brakes. Set the parking brake and perform a runup to verify that the parking brake is operating correctly.

Flight Instruments

Magnetic Compass Check presence, legibility and date of the compensation card. Check the smooth functioning of the magnetic compass. A nervous or otherwise unstable compass indicated a vibration or magnetic field problem. One


should be familiar with generic magnetic compass turning errors in tuning or accelerating flight.

Airspeed/Altitude Indication Check the logic and smooth functioning of the pitot/static related indicators. While increasing speed do not allow the speed to increase above VNE. While decreasing speed do not stall the aircraft. Indicated situation should follow actual situation instantaneous. Lagging or “sticking” indication is reason for complaint.

Avionics

COM Check the correct functioning of the radio. Tune in to a frequency given by ATC and check whether both receiving and transmitting levels are acceptable.

XPDR Check the functionality of the transponder. Ask a transponder code of ATC and ask whether they receive the signal. They should check for the primary and secondary signal including altitude. Try to send an ident and ask ATC to reply via radio when they have received it.

Skyview System

General Verify that the database is current. Verify that software settings are applicable to the AC4 and unchanged versus the information contained in the flight manual.

Artificial Horizon Check the logical functioning of the artificial horizon. It should be possible to see the effects from both roll and pitch on the instrument instantaneous and reflecting actual pitch and roll. The aircraft indicator symbol should be adjustable both up and down.

Turn and Bank Indication Check the logical functioning of the turn and bank indicator. It should be possible to see the effects from both left and right bank on the instrument. Furthermore, check the functioning of the slip indicator. Slipping the aircraft both to the left and to the right should result in a logical indication. Check accuracy of the instrument by timing a full 360 turn.

GPS Check the functionality of the GPS. See whether the reception of satellite signals is sufficient. Furthermore, check the navigation facility by trying to navigate for a short period to an airfield or beacon in the neighbourhood which is available in the data base.

OAT Indicator The OAT indicator shows the outside air temperature measured on lower side fuselage. The temperature indication can be correlated to the temperature ATC has available on the airfield at the moment of take-off. The functionality can further be checked by the fact that usually the temperature decreases with increasing altitude. Be aware that in certain meteorological


conditions, the temperature will increase with increasing altitude (inversion). If needed consult the meteo office for further information on the day of the test. OAT indication should not change with any change electric power or environment situation. Changed or erratic OAT while transmitting on the Com radio indicates a degradation of the sensor wire shielding. The OAT can also be correlated to the engine MAP temperature; however the MAP has engine related thermal influences so that values will not be identical, but behaviour in climb should be comparable.

PowerFLARM Verify connection of PowerFLARM to Skyview. Verify traffic alerts as well as audio warning functionality.

Compass Check agreement of SkyView compass display with magnetic compass while executing turns.

Airspeed Indicator/Altimeter/Variometer Check agreement of SkyView airspeed and altitude readings with those of the conventional instruments.

Accelerometer Select the g-meter display and verify the indication to correlate with bank angle in turning flight. There is no need to deliberately attempt more than 2g.

Engine Management System (EMU)

EMU Check Check functioning of EMU display including the diming function. Prior to takeoff, follow startup and runup procedure according to the AFM. Check proper functioning of lane warning indicators according to the AFM.

RPM Indication Check the functioning of the rpm indication on the EMU display while moving from low to high rpm and reverse.

Fuel Pressure Indication Check the functioning of the fuel pressure indication on EMU display by switching from main to both to auxiliary pump and back. Fuel pressure indication should remain green in colour.

Oil Pressure and Temperature Indication Check the functioning of the oil pressure and oil temperature indication on the EMU display. Idle RPM will reduce the oil pressure and increasing power settings will increase the pressure. Indication should follow instantaneously. The oil temperature indication should remain relatively unaffected by the flight condition due to the thermostat employed in the oil system. Therefore, the oil temperature indication shall be checked in engine run up. However, verify in stabilized full throttle climb flight at 115km/h IAS that the temperature remains within limits. The limit values should likewise not be exceeded when adding to the displayed temperature difference of actual OAT to ISA+20°C condition.


EGT Indication Check the functioning of the EGT indication on the EMU display by changing the throttle setting. In idle conditions, the EGT of the various cylinders will have a significant spread, in stabilized conditions above 4000RPM the difference between the four EGT signals should be no more than 50°C.

CHT Indication The CHT indication should remain relatively unaffected by the flight condition due to the thermostat employed in the coolant system. Therefore, the CHT indication shall be checked in engine run up. However, verify in stabilized full throttle climb flight at 115km/h IAS that the temperature remains within limits. The limit values should likewise not be exceeded when adding to the displayed temperature difference of actual OAT to ISA+20°C condition.

Other Instruments

Fuel Quantity Indicator Check the functioning of the fuel quantity indicator by monitoring the indication during the flight. During the flight the indication should become less according the amount burned. The indication is only accurate in horizontal flight; however, the indication should be independent of the airspeed. Changing indication with changing speed gives reason to suspect a problem with the fuel ventilation and should be investigated immediately. Do not read the indicator in a turn or a sideslip. Check agreement of fuel quantity with indication of fuel sight gauge. Verify functioning of sight gauge LED lighting system,

Note the low-level warning shall not be tested in flight. With the low-level warning triggered the remaining useful flight time is very limited. In this case initiate an immediate landing.

Volt/Amp Meter Check the functioning of the volt/amp meter by switching master on and electric consumers (lights) on prior to engine start. The battery should be sufficient to maintain a Voltage above 12V, the Ampere meter should show a discharge depending on the amount of electric load. A regular twitch trigged by the ACL is normal. The voltage should immediately increase to 13.6V when the engine generator engages at engine speed above 2800RPM, the ammeter should immediately read a charging state.

Engine Run Time Counter Verify the engine run time counter by correlation to actual flight duration. Note that the run counter is triggered by pitot pressure. Hence no run time is logged in a ground run.

Flight Handling Tests

These tests come closer to the boundaries of the flight envelope and have to be tested with care. Gain sufficient altitude before starting these tests. Do not execute these tests in inadequate weather conditions. Do not omit this part of the maintenance check flight but schedule an additional flight. The flight handling tests address four items.


Normal Flight

In this item the pilot should comment on the normal flight handling. He can base his judgement on the experience gained on the type in previous flights. He should base his judgment on all items tested so far in the maintenance check flight. He should address flight handling, the possibility to trim the aircraft and the control authority.

High Speed

In this part of the test the pilot should fly speeds up to VNE. This speed should be approached carefully with sufficient altitude left for recovery since this speed will only be reached in a relatively steep dive. Since there is a risk of overspeeding the engine this has to be flown at idle power setting. Check the rpm at VNE. This should not be more than 4000 rpm). During the high-speed flight, check for excessive or unusual vibrations or buffeting. Check the fabric tension. When unusual vibrations are noticed, do not increase speed further. Gently pull out of the dive and return to the airfield as soon as practical for inspection.

Stall

Approach the stall with a speed reduction of approximately 2km/h/s. Trim the aircraft at 100 km/h IAS before starting this manoeuvre. When the airplane stalls, recover the aircraft in a normal way. This has to be done in a configuration with the flaps up and the power set to idle. Be aware that maintenance can influence the stall behaviour quite significantly. When it is known that maintenance has taken place which influences the stall handling characteristics a more elaborated program has to be flown. Contact the manufacturer prior to testing in this case. The stall speed found in the tests should correlate to the stall speed indicated in AFM.

05-50 Unscheduled Maintenance This maintenance manual is under progress. In case of any event such as structural overload, lighting or propeller ground strike which warrants inspection or repair bejond what is defined in this issue contact Light Wing AG.

05-50-01 Structure Dimension Check

Global structural dimensions need to be checked if doubts about the structural health are given such as after a reported structural overload. This check is performed by six free distance measurments on either side of the aircraft, ref. Figure 10.


Line No

Theoretical measure

Acceptable tolerance

1 1868mm ±0.5%

2 5364mm ±0.5%

3 4241mm ±0.5%

4 4593mm ±0.5%

5 5940mm ±0.5%

6 2083mm ±0.5%

Figure 10 Check distances, overview, side and front view

Line 1, 1856mm: The measurement is taken from the frontend center of the lower wing strut attachment bolt to the forward corner of the nose gear strut. Attention: the tape measure touches the belly panel. The actual measured value is a little longer, but sitll needs to be within the tolerances.


Figure 11 Line 1, 1856mm

Line 2 / 5348mm: Measurment is taken from the lower center of the outer wing tip bolt to the front edge of the nose gear strut.


Line 3 / 4226mm: Measurment is taken from the lower center of the outer wing tip bolt to the center of the lower wing strut bolt.


Line 4 / 4584mm: Measurment is taken from the upper center of the outer wing tip bolt to the center of the horizonal tail spar.



Line 5 / 5932mm: Measurement is taken from the upper center of the outer wing tip bolt to the edge of the vertical tail tube (shortest distance).


Line 6 / 2083mm: Measurement is taken from the edge of the horizontal tail spar tube to the edge of the vertical tail tube (shortest distance).



06 Dimensions and Areas

06-00 General

06-00-01 Coordinate System

An artificial datum point in front and below of the aircraft is defined. All data in this Manual refer to this datum in EX, EY and EZ coordinates. Level attitude is defined by the orientation of the lower door frame.

Axis System

X aft positive, origin 1.000 m in front propeller flange

Y right positive, origin on centre line

Z up positive origin 2.000 m below propeller flange

Design level attitude is defined by a 4° nose down inclination of the fuselage main beam.

06-10 Main Data

06-10-01 External Dimensions

Total Length (Spinner to rudder tip): 6.950 m Maximum Height (Approx. static gear loading empty): 2.670 m Maximum Fuselage Width: 1.250 m Wing span (incl. wing tips): 9.446 m Wing span (incl. wing tip lights): 9.565 m

06-10-02 Internal Dimensions

Cabin width (inside spacing canopy frame): 1.215 m Cabin height (floor to top canopy): 1.250 m

06-10-03 Wing

Area (projected): 12.70 m2 Root chord 1.481 m Tip Chord (excl. wing tips): 1.339 m

Root Incidence: 3.7

Tip Incidence: 3.7

Dihedral: 0.5


Sweep angle Leading edge: 0

06-10-04 Aileron

Area: (each) 0.435 m2 Span: (each) 1.829 m Displacement: Up 22° +-2° Down 20° +-2°

06-10-05 Flap

Area: (each) 0.660 m2 Span: (each) 2.290 m

Positions: Down 0/ 10 /24 +-2°

06-10-06 Horizontal Tail

Area: 2.250 m2 Span: 2.910 m Root Chord, (theoretical centre): 1.050 m Tip Chord, (theoretical tip): 0.633 m Root & Tip Incidences: 1.2°

Dihedral: 0

Sweep angle at hinge line: 0

06-10-07 Elevator

Area aft of hinge line (both sides): 0.946 m2 Span: 2.910 m Displacement: +30° +/-2º

-30 +/-2º

Figure 17 Elevator range

06-10-08 Trim Tab

At L/H elevator trailing edge

Main beam 4° dwn

REF = X-axis+30°

-30°

relative to WRT Reference System

Elevator rangeRoot & Tip Incidences1.2°


Span 900 mm Chord 65 mm Displacement up (for nose down) with elevator at zero +5° +/-2° Displacement down (for nose up) -27° +/-2°

Figure 18 Trim range

06-10-09 Flettner Tab

At R/H elevator trailing edge Span 600 mm Chord 65 mm Position with elevator UP -26° +/-2º Neutral position (with respect to horizontal stabilizer) -12° +/-2º Position with elevator DOWN +7° +/-2º

Figure 19 Flettner range

06-10-10 Vertical Tail

Area:* 1.207 m² Height:* 1.358 m Root Chord:* 1.327 m Tip Chord: 0.600 m

Sweep angle at leading edge: 35 Vertical tail incidence 0°

Numbers include theoretical area located in fuselage up to fuselage main beam.

Main beam 4° dwn

REF = X-axis +5°

-27°

Root & Tip Incidences1.2° Trim range


Main beam 4° dwn

REF = X-axis

-26°

-12°

+7°


Flettner rangeRoot & Tip Incidences1.2°


06-10-11 Rudder

Area:* 0.576 m² Span:* full

Displacement: Left/Right 25 +/-2°

06-10-12 Fuel System

Total volume: 90 litres Unusable volume: 4 litres

06-10-13 Landing Gear

X Y Z Direction

(zero load) Nose wheel ground contact point

1.460 0 751 -

Main wheel ground contact point

3.303 +/-0.958 751 tow in 0°

camber 0°

06-10-14 Engine and Propeller

The engine is installed with 0º right and 2º nose DWN (zero thrust, angle of engine shock mount cup orientation)


12 Servicing

For servicing the engine (oil, water) refer to applicable Rotax instructions (refer to Chapter 01-30 Related Publications).

12-10 Replenishing

12-10-01 Replenishment of Brake Fluid

Necessary Tools:

square key wrench (11) Allen key Beringer bleeding equipment Brake fluid Transparent hose

Procedure

1 Loosen LH and RH filling nipple (do not remove). 2 Remove the cover at the brake handle. 3 Attach bleeding equipment to one nipple. 4 Attach a transparent hose to the other nipple. 5 Slowly pump clean brake fluid in the system until it comes out bubble-free on the other side. Check the transparent hose. 6 Tighten nipple and remove transparent hose. 7 Pump on brake fluid until it comes out bubble-free on the top of the system. 8 Tighten nipple and disconnect bleeding equipment. 9 Reinstall cover at the brake handle. 10 Check correct braking pressure. 11 Check park brake function.


20 Standard Practices Airframe

20-00 General The design of the airframe is according to standard procedures and generally requires no special tools or procedures for maintenance other than presented in AC 43-13. Specific torque and tension values are given in the following.

20-10 Standard Practices Airframe

20-10-01 Standard Torque Values

The standard torque values for bolt connections are:

Thread Size Torque Value

M4 2 Nm

M5 3 Nm

M6 5 Nm

M8 11 Nm

M10 22 Nm

M12 37 Nm

These values apply for lightly greased bolt connections or connections with liquid bolt lock.

20-10-02 Cable Tensions

The following cable tensions must be adjusted in the respective control system:

Rudder control Aileron control Wing bracing

Without noticeable tension

100 N thru 200 N min.500N

In both control systems adjustment is done by means of turnbuckles.


The structural cables in the wing cannot be adjusted. If their tension is outside limits it is a sign of damage. In this case contact Light Wing AG


21 Environmental systems

The Lightwing AC4 is optionally equipped with a heating system

21-40 Cabin heating

Description

The AC4 features an optional cabin heating system which uses RAM air aft of the coolant radiator and guides it through an exhaust shroud. The heated air is further guided to a firewall mounted valve which either dumps the air back into the cowling area or, if the valve is selected by the pilot to ON, into the cabin below the instrument panel. The cabin control for this function is located on the centre pedestal below the instrument panel. Its function is “PULL” for cabin heating active and “PUSH” for cabin heating off. The cabin heating system exhaust shroud around the exhaust plenum chamber is designed as two half sheets which can be taken off the exhaust plenum chamber. A reqular crack inspection of the plenum chamber and the heat shround is mandatory to avoid CO-contamination in the cockpit.

Figure 20: Cabin heat assembly


24 Electrical Power

Description

The heart of the system is provided by the fuse box of the engine manufacturer. The Rotax generation system provides a 12/14V system voltage. On the airframe side, it further features a lead battery in the engine compartment, with a 16Ah capacity at 12.7 V. Control switches, indicators and distribution busses are provided.

Figure 21 Rotax el. Generation system

The engine control unit can be provided with electric power through three sources. In normal operation, there is a separate generator for the engine and for the airframe. In case the engine generator part fails the engine


continues running on the airframe generator which in this mode no longer supplies the airframe. In case of a dual generator failure the engine control is supplied by means of a manual activates back-up system drawing power only from the battery. In this mode, the usable time is limited by battery capacity. Engine ignition is through the Lane A and B which are selectable individual or as automatic combination. Both Lanes are switched OFF with a rotary key switch. This rotary switch is also used to disconnect the relays coil line for the backup power system to avoid engine operation without the key.


Figure 22 Electric system schematic


25 Equipment/Furnishings

25-10 Flight Compartment

Description

The cabin volume is separated from the rest of the fuselage by the engine bulkhead/instrument panel on the front and a lightweight textile curtain at the rear.

25-10-01 Seats

Description

Two seats with integrated head rest, with an adjusting range of approx. 8 cm are provided. The adjustment can be done only on ground. The seat is structurally supported by a FWD extending framework attached to the main cross beam and a secondary fuselage cross beam FWD of the seat. 4-point seat belts are anchored on the seat (lap belt anchor point moves with the seat) and the wing support frame (shoulder belt – combined point for both shoulder belts).


Figure 23: Seat

Figure 24: Seat support principle


25-50 Baggage Compartment

Description

A maximum of 25kg of baggage can be placed behind the seats, above the fuel tank, and can be secured by rings anchored at the main beam and at the composite fuselage frame. The fuel cell top surface is sized as loading bay to withstand maximum baggage mass g-loads. Protection from impacts (baggage drop during loading) is given by sandwich plates covered with carpet.

Figure 25: Baggage compartment panels


Figure 26: Luggage restraint anchor points on main beam


27 Controls

Description

The control system is designed with push pull rods and cables. All push pull rods feature spherical rod end bearings allowing system adjustment. The control cables are stainless steel and feature a 3mm diameter. At cockpit level, the control system consists of a central (single) control stick, two sets of rudder pedals, one flap actuator located at the cockpit ceiling, one elevator trim actuator switch. A general overview of the control systems is shown in Figure 27.

Figure 27 Control systems overview

27-10 Ailerons

Description

Aileron control is achieved when moving the control stick sideways. The control stick turns a torsion tube, which in turn actuates two cables via a bell crank. These two cables are routed up and then forward, guided by pulleys before arriving at a bell crank in the cockpit ceiling. This bell crank is connected to two pushrods (Figure 28) entering the wing. These spanwise


pushrods are connected to two chordwise pushrods, actuating both ailerons (see Figure 29). Polyamid control stops are placed on the fuselage centre beam acting at the rocker type bell crank connecting the torsion tube to the cables. The cable part of the system can be adjusted by a turnbuckle in the vertical moving part of the system. An aluminium fixed trim tab is placed on the right aileron.

Figure 28 Aileron actuation, fuselage part, location and principle of control stop

Figure 29 Aileron actuation, wing part

Aileron Rigging

Aileron (and Flap) are in zero position with the lower surface aligned with the main wing spar to spar tangent on the lower side. The zero position can be set using rod end adjustment range.


If the gearing is not correct it is a sign of internal deformations. In this case contact Light Wing AG.

27-20 Rudder

Description

The rudder is commanded by two sets of non-adjustable rudder pedals connected to control cables which cross each other while moving aft (see Figure 30). Cable tension adjustment is achieved by turnbuckles at the end of the cables close to the rudder. A bell crank connects the cables to the torsion tube placed at the hinge line of the rudder. Each set of the pilot/co-pilot rudder pedal sets are interconnected left and right by a common torque tube which penetrates the fuselage main beam. The penetrations house nylon bearings in stainless steel cups. The pedals are interconnected via the nose gear steering link which makes the rudder control a closed loop system. The fixed control stop is located at the rear end of the fuselage main beam and limits the travel of the rudder actuation arm. A fixed trim tab is placed on the rudder.

Figure 30 Rudder actuation and principle


Figure 31 Rudder pedal mounting

Rudder Rigging

The first step in rigging of the system is to center the nose gear with left and right rudder pedals aligned. After this the rudder cable length is adjusted such that the rudder is centered.

27-30 Elevator and Tab

Description

The elevator control is commanded by moving the control stick forward and aft. The control stick actuates a pushrod leaving the control stick in aft direction. Via two gearings at bell cranks the actuation is delivered at the torsion tube at the leading edge of the elevator, which is just aft of the hinge line of the elevator. The path travelled from control stick to elevator hinge line is shown in Figure 32. The fixed control stop is located at the intermediate bell crank. This bellcrank incorporates a mass balance which has a non-linear characteristic versus the elevate static hinge moment.


Figure 32 Elevator actuation, (orange=bearings, red = massbalance)

A trim tab is employed on the left-hand elevator side and controlled by an electric actuator. The linear servo is mounted in the elevator, near the hinge line pivot. The trim actuation control is on the control stick, the indication by means of a multi LED indicator on the instrument panel.

Figure 33 Trim servo and tab

A further Flettner tab is mounted on the right-hand elevator to reduce elevator hinge moments.


Elevator Rigging

For all movables on horizontal tail (elevatror, trim, flettner) adjust the respective zero position. If resulting deflections do not correspond to the defined values it is a sign for deformations in the system. In this case contact Light Wing AG. Note that the zero position of the elevator is with respect to the horizontal stabilizer, see Figure 17

27-50 Flap System

Description

The left and right flap are synchronised by a mechanical link provided by the actuation system. The flaps are moved by means of an electric actuator (see Figure 34). Three flap positions (UP, 10°, 24°) are defined for cruise, take off and landing. Full up and full down are limited by internal limit switches in the actuator, preventing the actuator to block at its physical travel end. The intermediate position is marked on both sides of the bellcrank support as an indication visible for both the pilot and co-pilot. The actuator moves a pushrod, connected to the flap spar acting as a torsion actuator rod parallel to the flap hinge line. The flap actuation path is shown in Figure 35 .

Figure 34 Flap actuation (green actuator, red control rods)


Figure 35 Flap actuation unit

Flap Rigging

Flap (and (aileron) are in zero position with the lower surface aligned with the main wing spar to spar tangent on the lower side. The zero position can be set using rod end adjustment range. If the gearing is not correct it is a sign of internal deformations. In this case contact Light Wing AG.

fwd

Pilot indication


28 Fuel

Description

Fuel is stored in a single composite fuel tank behind the seats. The tank capacity is 90 liter. On the tank bottom, a sump volume is present. Bulkhead penetrations and a fuel strainer are mounted.

Figure 36 Fuel tank and its integration

Downstream of the fuel tank there is a shut off valve and a filter with a sediment volume (gascollator) and finally the dual fuel pump unit with internal check valves. The fuel shut off valve and fuel filter are mounted on the left of the fuselage main beam in front of the pilot. The fuel injection pump unit is mounted below the main beam, in front of the cross beam. Except for a fine fuel filter, NO valve, sensor or other intermediate element is employed downstream of the fuel pump unit up to the engine inlet. This part of the system, during operation is pressurized at 3 bar. The fuel tank further has a drain valve and connections for the return line, an opening for a capacitive sensor and the filling connection. A sight gauge for pre-flight check of the content is on the pilot side. A low level sensor is installed in the header volume. The filler neck is located on the right hand empennage panel.


Figure 37 Fuel system schematic

The system can be drained through the tank. A (water) contamination collection sump is present in the lower part of the tank. Just above is a 4 liter header volume to ensure uninterrupted fuel supply. The fuel cell ventilation features four pick up points which route high over the cockpit frame and high along the rear luggage volume limitation. The exit is one combined outlet at the airplane aft of the tank on the bottom empennage panel on the right side.

Figure 38 Fuel venting system


31 Indicating and Recording Systems

31-10 Instrument & Control Panels

Description

Figure 39: Instrument panel layout

The control and indicating essentially consists of the instrument panel, ref. Figure 39. For all electric and pneumatic instruments, electric and electronic units and associated wiring standard practices as outlines in AC 43-13 apply. For electronic units refer to the respective manufacturer information.

Note Approved software revision for the engine monitoring unit EMU912 is designated " EMUevo SW 1.41". Only this, or later approved revisions as mandated be revision of this handbook or by respective service information issued by Light Wing AG is approved foir use in the AC4 type airplane.

Note Changing airframe related software settings, such as speed limits or units used, in the multifunction display "Skyview" is not permissible. In case of doubt of theses settings contact Light Wing AG.

Note For approved firmware and database for the FLARM contact Light Wing AG.


32 Landing Gear

Description

The AC4 has a tricycle landing gear with steerable nose wheel. The nose gear leg passes through the fuselage main beam (Figure 40). An elastomeric insert is used to provide the spring/damping characteristics of the nose gear. Nose wheel steering rotation is actuated by a direct connection to the rudder pedals using pushrods. The pushrods feature a fire sleeve protection at the firewall penetration. The nose gear wheel is a 4.00-6” rim with 15*6.00-6 tyre (Beringer P/N wheel JAB02)

Figure 40 Nose landing gear

The nose gear is equipped with a wheel fairing featuring an aerodynamic surface for directional stability (see Figure 41). Flight without nose gear fairing is not permissible. For the main gear the fairings are offered optional.


Figure 41 Nose landing gear wheel fairing

The main landing gear leg is a machined steel spring connected by brackets to the fuselage cross beam, see Figure 42.

Figure 42 Main landing gear connection to fuselage


32-40 Wheels and Brakes

Description

The wheels and brakes are produced by Berringer. The wheels have a 4.00-6” aluminium rims and 15*6.00-6 tires (Berringer P/N wheel RF-004(B)). Central braking is present at the main gear wheels, using floating disk brakes, actuated by a single break handle placed on the main control stick (Berringer P/N HAB02 brake cylinder; HZA04 pressure limiter; brake handle HAB02). The brake handle incorporates the brake fluid reservoir. Fluid filling control is given by the adjustment travel range of the brake lever.

Figure 43 Gear leg, axle and brake cylinder assembly

For removal and reinstallation of bearings as well as for maintenance of the disc brakes refer to applicable Berringer maintenance instructions.


34 Navigation

34-10 Flight Environment Data

34-10-01 Pitot/Static System

Description

The Pitot port is located in the left wing, at the connection of the wing strut. Associated pressure tubing is routed thought the wing, then along the fuselage frame to the centre of the instrument panel. Static pressure is taken from the interior of the fuselage and routed to the instrument panel along the fuselage centre beam. System drains are located aft of the co-pilots seat, visible for pre-flight inspection.

Figure 44: Pitot tube at left hand wing strut interface


Figure 45: Pitot tube, with optional aerodynamic strut cover

Figure 46: Pitot/static system drains under Co-pilot seat

The pitot-static system serves the airspeed and altimeter instruments but also the ADAHARS and a pressure switch for operation hour counting.


Figure 47: Pitot-static routing


51 Standard Practices and Structures – General

51-30 Materials

Specification Used on Primary structure & Control system

aluminium 6082T6 (AlSi1MgMnT6) fuselage main beam, framework tubes, control system tubes, brackets, wing battens

aluminium 2024 control system tubes, structural struts

aluminium 7020 structural tubes

aluminium 6060T66 fuselage cross beam, brackets

aluminium 6005 & 6106 strut extrusions

steel 1.7218 (25CrMo4) welded elements such as engine mount & centre part of fuselage interface to wing; brackets, fittings on fuselage main beam

stainless steel cable 1.4401, “Litzenseil 6*19” Control and bracing Cables D=3mm; swaging by „Brugg“

Secondary structure

Glass fibre pre-preg Fuselage covers, empennage panels and cowling Carbon fibre pre-preg

stainless steel 1.4307 (X2CrNi18-9 / AISI304L

Firewall (0.4mm)

Airex R63.50 foam Leading edge contour shape on aluminium tube, below surface fabric. Intermediate stabilizer contour ribs

Airex R63.80 foam Stabilizer root ribs

Note: For repair on any composite component contact Light Wing AG.


52 Doors

Description

The aircraft has one door on each occupant side. The doors are top hinged (i.e. open upwards) and feature a turning locking mechanism.

Figure 48: Door lock actuation (inside)

For lubrication the inner part of the mechanism is accessible from the inside after removal of the outer and inner handle parts.


53 Fuselage

Description

The fuselage is constructed around a central load bearing aluminium tube: the main beam (see Figure 49).

Figure 49 Main beam

The second load bearing element is an aluminium box section frame: the cross beam (See Figure 50).

Figure 50 Cross beam


For the attachment of the wing, an aluminium and steel tube frame is connected to the main and cross beam. This frame consists of (from front to rear) the

base brace

cabin bearing structure

cabin support

rear cabin struts.

The complete configuration is shown in Figure 51, including the wing attachment locations.

Figure 51 Wing attachment to fuselage (red), strut connection (green)

The fuselage centre beam provides mounting hardpoints for

Engine mount,

Nose gear,

Front wing frame work support,

Rudder pedal bearings,

Main control bearing and bell cranks,

FWD seat support,

Fuselage cross beam and respective struts,

Luggage restraint,

Horizontal stabilizer support brackets,

Vertical stabilizer mounting penetrations.

It further supplies mounting points for the optional

Ballistic recovery system BRS,


The air tow winch and hook connection.

The fuselage cross beam acts as structural connection for:

The main landing gear,

The front and rear cross beam struts,

The wing struts,

The pilot seats AFT support,

Cabin support

The outer surface mounting composite bulkhead.

The fuselage is covered by composite shells (see Figure 52):

Top and bottom cowling;

Windshield side frames and transparency with instrument panel glare shield;

Wing top centre panel with fairing to windshield;

Belly panel;

Doors;

Top and bottom empennage panel;

Tail cone.

Two bulkheads are used as structural interfaces to align the covers

A composite bulkhead between the empennage parts of the cover and the belly panel;

A stainless-steel engine bulkhead between the cowling and belly panel respectively the windshield frame. This bulkhead also serves as fire wall with respective system penetration means.

The windshield, belly panel, glare shield, FWD door frames form one assembly which serves as mounting for the engine fire wall. This assembly and the cabin composite frame are the only cover which cannot be removed from the airplane individual in normal maintenance. To do so the firewall and several struts penetrating thought it must be disassembled first. All other cover elements can be un-mounted for convenient access to systems and maintenance. The belly panel is drained at the main gear penetrations and at the lowest point – also the lower empennage cover features a specific drain location.


Figure 52 Fuselage panels

The engine cowlings are attached to the engine bulkhead frame plane by means of bolts. A view of the cowling attachment bolts is given in Figure 53.

Figure 53 Cowling attachment location

The cockpit bottom ‘belly panel’ is connected to the engine bulkhead in the front (Figure 54) and to the cabin composite frame at the cross beam in the rear (Figure 55).


Figure 54 Belly panel connection to firewall

Figure 55 Belly panel connection to cabin composite frame

The bottom empennage panel is connected to the bulkhead and framework in the front (Figure 56) and to the horizontal stabiliser main spar supports in the rear (Figure 57).

Figure 56 Bottom empennage panel to cabin composite frame connection


Figure 57 Bottom empennage panel to main bean connection

The top empennage panel is connected to the aluminium/steel framework and the bottom empennage panel as well as to the wing centre panel. Details are shown in Figure 56 and Figure 57.

Figure 58 Top to bottom empennage panel connection

When removing or re-installing the top empennage panel care must be exercised with the antenna wire of the ELT.


55 Stabilizers

Description

The horizontal and vertical stabilisers consist of an aluminium tube framework covered with thermal shrinking tensioned fabric. They provide mutual support by struts attached to the tubes in front of the hinge line.

Figure 59 Tail structure

55-10 Horizontal Stabilizer

Description

The horizontal stabiliser is connected to the fuselage centre beam via a bolted connection to connecting flanges riveted to the fuselage centre beam.


55-30 Vertical Stabilizer

Description

The vertical stabiliser’s two main load carrying spars pass through the entire fuselage centre beam. The mounting of the vertical stabilizer tubes is done using riveted stop rings to avoid movement and liquid shim to avoid chaffing.


56 Windows

Description

Pilot and occupant external vision is provided by a windshield, windows in the doors as well as windows in the top empennage cover. All windows and the windshield are adhesively bonded to the respective supporting composite covers. The windshield is bonded from the outside, all other transparencies from the inside. In addition, the windshield attachment is

reinforced by bolt connections, see Figure 61. All transparencies are cut from flat polycarbonate and bent to shape upon installation. Thickness of the side transparencies is 2mm. Thickness of the windshield is 3mm.

Figure 60: Windshield

Figure 61: Windshield reinforcement bolts


57 Wing

Description

The AC4 has a thermal shrinking tensioned fabric skin wing. Structurally, the wing consists of two aluminium tube spars, held in place by aluminium tube ribs, tensioning cables and a rear lift truss strut combination. The spars lie on the leading edge and forward of the control surface hinge lines, as can be seen in Figure 62. The ribs consist of aluminium tube battens. They are placed with an equidistant pitch and are connected to the spars and restraint in spacing by vacuum moulded parts as shown in Figure 63. Steel bracing cables extend from the wing root to the wing strut locations and the wing tip area to maintain the planform angularity. The wing surface consists of heat shrinkable rib-stop polyester material and retains the wings aerodynamic form with help from the wing battens. The leading edge shape (in front of the wing spar) is shaped by machined thermoplastic foam (Airex R63.50).

Figure 62 Wing structure, top view (bracing cables in red)


Figure 63 Wing rib battens

Rigging/De-rigging

For reduction of required hangar space, the wings can be taken off. For this purpose, the following system connections need to be opened and closed:

bolted aileron system connection

bolted flap system connection

electric connection (wing tip lights) is by means of wing root mounted connectors

pitot system

No other system is involved. The structural connections that need to be opened/closed are the wing strut connections as well as the wing to fuselage connection. The wing twist and incidence is determined by a secant tool as shown in Figure 64.


Figure 64 Wing structure, secant tool for rigging check

The tool is used at stations between the rib battens along the span. The nominal angle determined by the Inclinometer is 0°. The acceptable general tolerance is 0.5°. However, the difference between the average angle left and average right shall not be more than 0.5°, nor should the tolerance within one wing be more than 0.5°. Further the angle at the wing tips may not be more than at the root.

Figure 65 Wing structure, acceptable tolerances for wing twist and incidence

If wing incidence or twist is outside acceptable tolerances it is a sign of damage. In this case contact Light Wing AG. Before doing so measure the wing bracing cable tension (nominal range 500 to 800N)


61 Propeller

Description

Propeller Neuform

Make: Neuform Composites GmbH & Co Type: CR3-75 3-blade Diameter: 1.75m Blade angle: 25° measured 365mm from hub center using the Neuform tool, which

determines the gaugeable angle (Secant). Refer to Figure 66. Torque Bolts: 25Nm

Figure 66 Definition of the gaugeable angle


71 Power Plant

71-10 Cowling

Description

The cowling is made from glass fibre composite in an upper and lower part. Both are removable from the airplane as a whole using bolted hardware. For pre-flight inspection a hatch giving access to the oil and coolant water reservoir is provided. The lower cowling incorporates the air ducting to the oil radiator and the engine air filter. The principle arrangement of components is depicted in Figure 67.

Figure 67 Powerplant: arrangement of components (cabin heating optional)


Figure 68 Cowling inlet for engine air and oil radiator

Figure 69 Cowling inlet for cylinder cooling and coolant radiator (note: inlet of optional

cabin heating system is right aft of coolant radiator)


71-20 Engine Mount

Description

The engine is structurally mounted to the aircraft by means of a welded steel tube framework; see Figure 70. The framework is bolted to the fuselage centre beam.

Figure 70 Engine mount

The engine mount also provides the mounting base for the coolers as well as a stabilization for the belly panel.

71-30 Fire Seals

Description

The engine cowling area is the only designated fire zone of the AC4 airplane. The basic firewall is a 0.4mm stainless steel sheet. It is installed along the separation line of cowling and fuselage covers in a self stiffening Z-shape. Additional stiffening is given by the oil reservoir mounting, the electric system unit mounting and additional stringers. Penetrations of the firewall and their respective protection means are

Landing gear control with flexible, textile (glass fibre) shrouds.

Fuel supply and return line with steel bulkhead fittings;

Engine control Bowden cables, sealed with high temperature silicone;


Electric cables sealed with high temperature silicone;

Fuselage centre beam tube opening is closed with stainless steel plates

Fuselage centre beam surface is protected by by textile aluminized glass fibre heat shield

Fuselage centre beam and engine mount interfaces are sealed with high temperature silicone;

No structural interface is given to composite parts, composite parts are in contact with the firewall only along the surface contour lip only through mounting hardware. The surfaces are separated by means of fireproof silicone. They are sealed both, in and outside, to prevent direct flame impingement as well as decomposition smoke inside the cabin.

Figure 71 Firewall seal principle

Fuel and oil lines within the cowling area are protected by fire-sleeves. The cowling as such is a hybrid design embedding a carbon layer in the otherwise glass fibr dominated structure for fire containment.


72 Engine

Description

Make: BRP-Powertrain GmbH & Co KG; Model: ROTAX 912iS Sport Fuel injection Engine Mode (non-certified) or

ROTAX 912iSC Sport (certified) EASA TCDS E.121 Power:

Version: fixed pitch propeller flange; with torsion shock absorber.

Details:

Naturally Aspirated 4 Stroke, 4 Cylinder Horizontally Opposed, single Central Camshaft, hydraulic Valve Lifters with automatic adjustment;

Liquid cooled cylinder heads; Ram air cooled cylinders;

Dry sump forced lubrication, with oil cooler and oil tank;

Dual ignition with breakerless capacitor discharge design;

Fuel injection, pressure supplied by a dual electric fuel pump;

Prop drive via integrated gear box (1:2.43);

Coolant expansion tank;

Electric Starter with a external starter relays;

Dual Integrated AC generator for engine control and fuel supply, one generator co-used for the airplane system,

Thermostats for oil and water cooling system added.

For more detailled descrption refer to applicable BRP Powertrain publications.

Note Approved software revision for the engine control unit (ECU) is designated "130". Only this, or later approved revisions as mandated be revision of this handbook or by respective service information issued by Light Wing AG is approved for use in the AC4 type airplane


Figure 72 Rotax 912iSc/iS Sport


75 Air

Description

The engine takes its air from a separate NACA inlet on the right cowling side, see Figure 73. The air enters a separated volume into which the induction filter and engine air data sensor are mounted.

Figure 73 Air filter installation

Engine inlet air temperature is sensed next to the inlet filter.

75-20 Cooling System

Description

The cylinder heads are cooled with a liquid cooling system, while the cylinders are cooled by the air flowing around them. The liquid is circulated by a water pump that is driven directly from the crankshaft. An expansion tank is installed above the engine, from where the cooling liquid flows into the cooling radiator. The pump delivers the water to the cylinder heads. An overflow bottle is also installed in the system. The coolant system radiator is circulated only when a thermostatic valve opens. The radiator is mounted below the engine in the forward part of the cowling and attached by a removable sub-frame which in turn is mounted to the engine mount. It is supplied with ram cooling air from a cowling inlet. Radiator warm air is dumped into the engine compartment. The cylinder head cooling system is composed of components supplied by BRP powertrain, the engine manufacturer, and by Rotax Franz (water thermostat).


The radiator is supplied with cooling air from the cowling centre front inlet.


76 Engine Controls

Description

The engine side of the engine control is thought the engine manufacturer supplied engine control unit (ECU). The airframe side engine control compromises the following:

A throttle vernier control for the pilot in the left side of the instrument panel, mechanically driving directly the throttle valve;

Control switches serve the functions according Rotax Installation manual.

The control switches are grouped in the instrument panel and compromise

A keyed rotary switch providing the functions:

o OFF o LANE A o LANE B o LANE A&B (=normal flight position) o Start power (spring loaded to return to LANE A&B) o Starter (spring loaded to return to LANE A&B)

Two toggle switches for the fuel pumps:

o Main pump ON/OFF (guarded) o Aux pump ON/OFF

Power is available to the fuel pump circuit in all positions of the rotary switch except the OFF position.

A guarded backup switch providing direct battery power to the engine electric circuit in the case of a generator failure

There are further two warning lights for LANE A & B


78 Exhaust

Description

The exhaust system is mounted to the engine bock. The muffler is located below the engine such that the length of all four exhaust discharge stacks is similar. The design of the engine exhaust is shown in Figure 74.

Figure 74 Exhaust system

The exhaust discharges to the left through the lower main air dump opening.


79 Oil

Description

The engine is provided with a dry sump oil system, which includes a pump and an oil pressure regulator. The oil pump is driven by the crankshaft. The oil pump sucks the oil from the sump, and delivers the oil through a filter to the moving components requiring lubrication. An oil drain screw is located at the bottom of the engine block. An oil temperature sensor is located next to the pump. The oil cooler is located on the right side, and supplied with cooling air from a NACA type cowling inlet, which also serves as its structural mounting. The oil cooler air dump is into the engine compartment. The oil reservoir is mounted to the firewall by means of a bracket, which stiffens the firewall. Oil lines are covered with fire sleeves.


91 Charts

Figure 75 Wire routing (Power)


Figure 76 Wire routing (RF)


AC-4 Maintenance Check Flight Form

Date: Pilot: Tacho: hrs QNH: hPa Empty mass: kg

Serial number: Take Off: : Wind: / Take off mass: kg

Registration: Observer: Landing: : OAT: C Fuel: liter

Duration: : Remarks:

Performance tests

Configuration IAS

(km/h)

Altitude

begin (ft)

Altitude

end (ft)

Elapsed

time (min)

RPM

(min-1

)

Oil press.

(bar)

Oil temp

(C)

Fuel press.

(bar)

CHT

(C)

Climb:

Cruise:

Full throttle level flight:

System tests + = acceptable - = not acceptable 0 = not installed

Flight controls: Elevator: Ailerons: Rudder: Flaps: Trim:

Engine controls: Throttle: Fuel pump switches: Rotary engine key: Back-up switch: -

Flight instruments: Magnetic compass: Airspeed: Altimeter - -

SkyView: Compass: Airspeed: Altimeter GPS: Display brightness:

Artificial Horizon: g-meter: Data base expiration: OAT: Audio feed:

Avionics: COM: Intercom: PTT (also Co-pilot): XPDR: FLARM/traffic alert:

Electrics NAV light: Anti-collision light: 12V outlet: USB power outlet: CB's:

EMU: RPM: Fuel pressure: CHT: EGT: MAT:

Oil pressure: Oil temperature: Lane indicators: Display brightness: MP:

Throttle position: Lane Voltage: Warnings: - -

Other instruments: Fuel quantity: Sight gauge / light: Amp meter: Volt Meter: Hour counter:

Flight handling tests Consult airplane flight manual prior to executing these tests, gain sufficient altitude before starting the manoeuvres

Normal flight: Flight handling: Min trim speed: km/h Max trim speed: km/h Control authority:

High speed: Vne (vibration): Idle RPM at Vne: min-1

Stall (power idle): Stall flaps UP: km/h Stall flap 24°: km/h Stall handling:

Steep turn: 45 bank: 60 bank:

Result Released for further service:

Released for further service after complaints have been resolved:

New maintenance check flight necessary after complaints have been resolved:

Signature:

Documents

LightWing AC4 Maintenance Manual