Ae2355 Manual

PREPARED BY S.RAJKUMAR Page 2

TABLE OF CONTENTS

AE 2355

AERO ENGINE LABORATORY MANUAL

Expt LIST OF EXPERIMENTS Page no

Introduction – piston engine

1 Stripping of a piston engine

2 Engine (Piston Engine) - cleaning, visual inspection, NDT checks.

3 Piston Engine Components - dimensional checks.

4 Piston – Engine reassembly.

5 Propeller Pitch Setting

Introduction – jet engine

6 Stripping of a jet engine

7 Jet Engine – identification of components & defects.

8 Jet Engine – NDT checks and dimensional checks

9 Jet Engine – reassembly.

10 Engine starting procedures.

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INTRODUCTION – PISTON ENGINE

Piston engines are internal combustion engines that burn a mixture of fuel and air inside a

combustion chamber. The chamber is provided with a piston that moves within the compression

chamber. The energy for the movement of the piston is provided by the air-fuel mixture. Piston

engines operate similar to the car and other automobile engines. In its basic operation, a valve in

the engine permits air into the chamber (called the cylinder) which is compressed by the moving

piston. When an appropriate compression is reached, fuel is allowed into the compressed air

through another inlet as a fine spray. Finally, the compressed fuel-air mixture is ignited with a

spark provided by a spark plug, which causes the mixture to explode violently. The explosive

power is used to move the piston back, and remove the exhaust gases from the compression

chamber. The return movement of the piston is conveyed to the wheel and fans of the aircraft

which causes it to rotate at high speed. In a propeller powered aircraft, much of the thrust is

created by the propellers, which creates the upward lift for the aircraft.

The general aircraft piston engine used for thrust generation, consist of the following basic

components.

CRANK CASE:

The crank case of an engine is the housing that houses the various components

surrounding the crankshaft. Therefore it is the basic foundation of the engine. The crank case

performs the following functions:

It contains bearings in which crankshaft revolves.

It provides a tight enclosure for lubricating oil.

It supports various internal and external mechanism of power plant

It provides a support for attachment of cylinder.

It prevents the misalignment of the shaft and its bearings.

BEARINGS:

Bearing is any surface that supports or is supported by another surface. The bearings in

any aircraft engine are designed to minimize the friction and wear resistance. They must reduce

the friction of moving parts and also take the thrust loads, radial loads or combination of both.

SRINIVASAN ENGINEERING COLLEGE,

PERAMBALUR – 621 212

DEPARTMENT OF AERONAUTICAL ENGINEERING

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CRANK SHAFT:

The crankshaft transforms the reciprocating motion of the piston to rotating motion for

turning the propeller. It is a shaft composed of one or more cranks located at definite places

between the end. Since the crank shaft is the backbone of the engine it is subjected to all forces

developed within the engine and hence should be strongly constructed.

CONNECTING ROD ASSEMBLIES:

Connecting rod is the link which transmits forces between the piston and crankshaft of an

engine. It transmits the reciprocating motion of the piston to the rotating movement of the crank

shaft. The principle type of connecting assemblies are the

Plain type

Fork and handle type

Articulated type

PISTON:

The piston is a plunger that moves back and forth or up and down within the engine

cylinder barrel. It transmits the force of the burning and expanding gases in the cylinder through

the connecting rod to the engine crank shaft. As the piston moves down the cylinder, during

intake stroke, it draws in the air fuel mixture. As it moves up, it compreses the charge. Ignition

takes place and the expanding gases cause the piston to move towards the crank shaft.The piston

forces the burnt gases out of the combustion chamber during the next stroke.

CYLINDERS:

The cylinder of an IC engine converts chemical heat energy of the fulel to mechanical

energy and transmits it through the connecting rods to the rotating crank shaft. The cylinder

assembly used for present day engines usually includes cylinder barrel, cylinder head, valve grid,

valve seats, rocker arms, cooking fins

VALVES:

In general a valve is a device for regulating or determining the check on the flow of a

liquid or a gas by a movable part which opens or closes into a passage.The main purpose of a

valve in IC engine is to open and close parts which are into the combustion chamber of the

engine namely intake and exhaust ports.The valves are associated with valve guides,valve seats

and valve springs.




PROPELLERS:

They are essential aircraft parts that provide the necessary thrust for moving the aircraft.

The propeller is connected to the engine by means of a shaft.The propeller consists of two or

more blades and a central hub to which the blades are attached service. For an aircraft to remain

in an airworthy condition the following conditions have to be fulfilled.

Periodic inspection

Repairs

Overhauls and replacements




EX. NO:1 STRIPPING OF PISTON ENGINE

AIM:

To dismantle a piston engine and study its particular components.

TOOLS REQUIRED:

Special tools for notching crank shaft.

Universal socket for spark plug

Selected spanner no: 6-19

Ring spanner no: 6-22

Adjustable spanner

Plier, cutter and screwdriver

Value depression tool

Crow foot spanner

Simple aircraft piston engine

PROCEDURE:

1. Remove spark plug and rocker curves.

2. Remove starter and accessories.

3. Turn the engine over such that cylinders are upper most.




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4. Remove controls completely with universal joints.

5. Remove air scoop, plug leads, distribution covers.

6. Remove induction system with carburetor.

7. Unscrew push rod ball socket from rockers.

8. Take out push rod and push rod covers.

9. Remove cylinder baffle plate.

10. Remove cylinder.

11. Remove piston rings.

12. Extract gudgeon pin, air clip.

13. Withdraw gudgeon pin and piston. Remove magnetos.

14. Remove gearbox with timing gear cover.

15. Turn the engine cover on its stand. Remove starter.

16. Remove adaptor, thrust bearing cover and top cover.

17. Detach big and bearing caps. Withdraw connecting rod.

18. Remove main, intermediate bearing caps.

19. Lift crankshaft. Unscrew idle gear hub bolt.

20. Draw off gear wheel. Remove magneto drivers.

21. Unscrew camshaft gagging the gear.

22. Remove camshaft rear bearing bush.

23. Withdraw camshaft. Remove tappet and guides.

24. The parts are kept for visual inspection.

RESULT:

Thus the stripping of piston engine is carried according to instructions in the

manufacturer’s maintenance manual.

VIVA QUESTIONS:

Explain overhaul

What are the safety precautions while handling the engine?

Explain the purpose of push rod

What is the role of cam shaft




EX. NO:2 NDT CHECK FOR AIRCRAFT COMPONENTS

AIM:

To perform the NDT checks on aircraft components

APPARATUS REQUIRED:

Aircraft component

Kerosene

Lubricating oil

French chalk

Methylated spirit

Heating source

PROCEDURE:

I. For parts that can be removed from aircraft

a) For these components, hot fluid chalk method is used cleaning must be done

b) A mixture of three parts of kerosene and one part of lubricating oil is heated at 90 – 95oC.

c) The removal components such as piston’s connection rods, cylinders, combustion

chamber are dipped in the hot fluid

d) Take the component out and dried out apply French chalk on it.

e) Extra French chalk is to be removed by tapping.

f) Then cool the component, the contraction of the piston on cooling will force the oil out of

any crank and stain the French chalk with a yellowish color.

II. For components that cannot be removed from aircraft.

a) For a components that cannot be removed from aircraft such as landing gear mounting,

cold fluid chalk method is used cleaning is done.




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b) French chalk is mixed with Methylated spirit and applied on the components that are to

be checked

c) Excess chalk is removed by tapping.

d) Methylated spirit will evaporate off leaving the cracks stain with French chalk

RESULT:

Thus the NDT checks have been performed on aircraft component.

VIVA QUESTIONS:

What are the NDT techniques used in inspection?

What techniques is used for inspecting internal defect

Explain some defects occur in piston engine components?

How to monitor the health of engine condition?




EX. NO:3 PISTON ENGINE COMPONENTS - DIMENSIONAL CHECKS.

3.(a) VIEWING PROCEDURE OF CONNECTING ROD

AIM:

To perform maintenance and inspection on connecting rod.

TOOLS REQUIRED:

Surface plate

Micrometer

Dial gauge

Vernier caliper

Telescopic gauge

Tapered sleeve

Arbors

Plug gauge

PROCEDURE:

1. Check the connecting rod conditions,the big end caps for cracks and other surface defects

by hot oil and chalk method.

2. Check the rod for notches and abrasion.

3. Measure small end dia and compare with external dia of gudgeon pin.

4. Check the nip in the big end bearings.

5. Measure and check the diameter with internal dimensions of cylinder bore gauge.

6. To carry out the nip check,assemble connecting rod shell and cap as per assembly

sequence and tighten the bolts.

7. Tighten to 840 pounds inch and check diameter of big end bearing.

8. Check connecting rod for alignment.

9. Check connecting rod bolts for elongation and nuts for threads.

10. Check for hardness.

RECTIFICATION:

1. During the NIP check, if 0.004” doesn’t go inside machine the big end cap. If 0.006”

goes inside replace the bearing cap.




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2. Fitting and searing can be removed by stoning and polishing if not too deep.

RESULT:

Thus the connecting rod is viewed and its dimensions are measured as per instructions

in the manufacturers’ maintenance manual.

VIVA QUESTIONS:

Which type of material used to manufacture the connecting rod?

Different types of connecting rod?

What refer the big and small ends of connecting rod?

What is connecting rod?




3.(b) VIEWING PROCEDURE OF CRANK SHAFT

AIM:

To view the crankshaft and check out its dimensions.

TOOLS REQUIRED:

Surface table

V-blocks

Dial indicator

Vernier caliper

Micrometer

Magnifying glass

PROCEDURE:

1. Check for cracks by contact current method.

2. Check for corrosion, pitting etc..

3. Check for ovality and taperness using micrometer.

4. Check external dimensions of crank pin and journals.

5. Carry out rip check before measuring internal dimensions.

6. Check for central journal errors due to ovality.

7. Check the crank web for parallelism.

8. Check crank pin for parallelism. Error allowed is 0.0016” per unit length.

9. Check if propeller shaft has a tapered end in the hub.

10. Check propeller shaft for threads and keyways for burrs and beveling.

11. Check oil seal retainer and sealing for burrs and correct seating.

12. Carry out static and dynamic hardness tests.

RECTIFICATION:

1. Score, taper and ovality can be removed by grinding.

2. Slight score and pitting can be removed by grinding or dressing with carborundum or

polishing with emery paper.




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RESULT:

Thus the crankshaft is viewed and its dimensions are checked with the manufacturers’

maintenance manual.

VIVA QUESTIONS:

What is the purpose of crankshaft?

What is a journal?

What is the purpose of counter weight?




3.(c) VIEWING PROCEDURE OF CYLINDER ASSEMBLY

AIM:

To perform the task of maintenance and inspection of cylinder assembly.

TOOLS REQUIRED:

DIP basket

Stud removing tool

Spark plug insert tool

Hand vice drill bit

Drift and bore gauge

PROCEDURE:

CLEANING:

Clean the cylinder head with petroleum solvent. Dip it in petroleum agent using

cleaning basket.

VISUAL INSPECTION:

1. Inspect the cylinder head visually using a magnifying glass.

2. Inspect the cylinder for

3. Loose damaged studs.(replace new ones)

4. Loose spark plug (insert new oversize ones.)

5. Loose cracked valve guide.

6. Damaged mounting ports, rocker box cover

7. Cracked or damaged fins

DIMENSIONAL CHECKS:

1. Check internal dimensions of intake and exhaust valves.

2. Check diameter and roundness of guide bore with gauge.

3. Check wear and tear in rocker arm bush.

4. Dimension checks are done in processes.




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CYLINDER BARREL:

TOOLS REQUIRED:

Cleaning basket

Feeler gauge

Dial gauge

Bore gauge

PROCEDURE:

CLEANING:

Clean the barrel using petroleum solvent dipping it on the cleaning basket.

VISUAL INSPECTIONS:

1. In cooling fins, check for nicks and notches.

2. In barrel, check for cracks (result in rejection)

3. In skirt, check for cracks, bends, and breaks.

4. In mounting flange, check for nicks, cracks and warping.

5. Inside the barrel inspect for corrosion and scoring.

DIMENSIONAL CHECKS:

1. Maximum clearance between piston skirt and cylinder is 0.021”

2. Maximum taper of cylinder wall in 0.018”.

3. Maximum ovality is 0.018”.

RESULT:

Thus the inspection of the cylinder assembly is carried out as per instructions given in

manufacturer’s maintenance manual.

VIVA QUESTIONS:

What is cylinder head temperature?

Why fins are used?

What is cold spark plug?




3.(d) VIEWING PROCEDURE OF PISTON ASSEMBLY

AIM:

To carry out inspection on the piston assembly.

TOOLS REQUIRED:

Cleaning basket

Feeler gauge

Scale 12”

Telescopic gauge

Micrometer

Vernier caliper

PROCEDURE:

1. Check for completeness of the piston assembly and clean it by dipping in petroleum

solvent using cleaning basket.

2. Examine the piston surface thoroughly for excessive pitting, cavaties or surface

distortion.

3. Check the piston rings, grooves, piston pinholes and holes base for any damage.

4. Check side clearance between piston rings and piston (0.004”-0.0025”).

5. Check end clearance on wedge type piston rings.

6. Check inside diameter of piston pinhole (0.03”-0.004”).

7. Check clearance between piston skit and cylinder and piston dia top and bottom(0.021”).

8. Check outside diameter of piston pin against inside diameter of hole in piston(0.0002”-

0.001”).

9. Measure fit between piston and plug and check outside diameter of plugs(0.0002”-

0.001”).

10. Examine two interior surface of piston pin hole for corrosion and fitting.

RESULT:

The maintenance and inspection of the piston assembly has been performed according

to manufacturer’s maintenance manual.




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VIVA QUESTION:

What is manufacturer’s maintenance manual?

Explain the piston types?

Why piston rings are used?

What is meant by clearance?

What types of rings are used?




EX. NO: 4 REASSEMBLY OF PISTON ENGINE

AIM:

To reassemble the piston engine after inspection checks.

TOOLS REQUIRED:

Special universal socket for spark plug

Set spanners 6’-19’

Ring spanners 6’-22’

Adjustable spanner

Pliers and cutters

Screwdriver different sizes

Hammer

Value depression tool

Crow foot spanner

PROCEDURE:

1. Insert the tappet and the guides in the crank case.

2. Fix the camshaft after positioning bearing bush.

3. Fix the magneto drive gear.

4. Fix the idle gear and screw the hub bolt.

5. Fix the crankshaft and position the bearing caps.

6. Fix the connecting rod and the bearing caps.

7. Position the top crankcase and then tighten all bolts and nuts.

8. Fix the gearbox with timing gear cover.

9. Fix the magnetos.

10. Fix the position in the connecting rod.

11. Assemble the piston rings on the piston groove and insert the cylinder over piston and

tighten all cylinder large nuts.

12. Fix the cylinder baffle plates.

13. Position the push rod covers and push rods.

14. Fix the rocker shafts.

15. Fix the induction system and carburetor.

16. Fix the air scoop, plug heads with distribution cover.




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17. Fix the carburetor controls with universal rods.

18. Fix the starter and other accessories.

19. Fix the spark plug in cylinder head bush and tighten to connect torques and connect the

plug leads.

20. Fix the rocker covers.

RESULT:

Thus the piston engine in reassembled as per maintenance manual instruction

VIVA QUESTION:

What is ignition timing?

What is timing advance?

Define engine firing order?

What is backfiring?




EX. NO: 5.(a) CHECKING OF PROPELLER PITCH BALANCING

AIM:

To ensure the propeller blade twist is intact.

TOOLS REQUIRED:

Surface table

Degree marked protractor with mounting stand

PROCEDURE:

1. Attach the propeller on the hub stand and place it on the surface table.

2. Now position the protractor head near the propeller hub station with surface table.

3. Now check the angle of the blade near to the hub station.

4. The propeller stations are at a distance from the hub and tip varies from propeller to

propeller.

5. The blade angle is checked from the hub to the tip by moving the protractor in all

directions of the blade stations and also referred the maintenance manual for the

particular airplane adjustment.

6. The propeller track also checked with the help of weight gauge on the surface table.

RESULT:

Thus the propeller pitch is checked at various stations and compared with values in

maintenance manual.

VIVA QUESTION:

What is mean by pitch?

What is hub?

What are the Types of propellers?

What is the main purpose of propeller?




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EX.NO:5.(b) FIXED PITCH PROPELLER BALANCING

AIM:

To ensure the propeller is balanced horizontally and vertically.

TOOLS REQUIRED:

Propeller stand with knife-edge support.

Correct size mandrel

PROCEDURE:

1. Insert the mandrel in the propeller shaft hole.

2. Place the mandrel in the knife-edge.

3. Rotate the propeller and to vertical position and ensure it remains in this position without

moving.

4. The vertical balance is corrected by attaching a metal weight to the lighter side of the

hub. The amount of weight is determined by applying putty at a point normal to the

horizontal line. After balancing, the putty is weighed; a metal plate is cut approximately

equal in weight to the putty. The weight of the metal is adjusted for the weight of the

screw and the solder.

5. The plate is attached to the hub at the location normal to the counter shrunk screw.

Finally varnish is applied.

6. The horizontal balance can be adjusted on a wooden propeller by adding or removing

solder from the balance tip.

RESULT:

Thus the propeller is balanced both vertically and horizontally.

VIVA QUESTION:

Explain reverse pitch propeller?

What is feathering?

Why reduction gear box is used?




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INTRODUCTION TO JET ENGINE

The major components of a jet engine are similar across the major different types of engines,

although not all engine types have all components. The major parts include:

Cold Section:

Air intake (Inlet) — The standard reference frame for a jet engine is the aircraft itself.

For subsonic aircraft, the air intake to a jet engine presents no special difficulties, and consists

essentially of an opening which is designed to minimise drag, as with any other aircraft

component. However, the air reaching the compressor of a normal jet engine must be travelling

below the speed of sound, even for supersonic aircraft, to sustain the flow mechanics of the

compressor and turbine blades. At supersonic flight speeds, shockwaves form in the intake

system and reduce the recovered pressure at inlet to the compressor. So some supersonic intakes

use devices, such as a cone or ramp, to increase pressure recovery, by making more efficient use

of the shock wave system.

Compressor or Fan — The compressor is made up of stages. Each stage consists of

vanes which rotate, and stators which remain stationary. As air is drawn deeper through the

compressor, its heat and pressure increases. Energy is derived from the turbine (see below),

passed along the shaft.

Bypass ducts much of the thrust of essentially all modern jet engines comes from air from the

front compressor that bypasses the combustion chamber and gas turbine section that leads

directly to the nozzle or afterburner (where fitted).

Common shaft — The shaft connects the turbine to the compressor, and runs most of the

length of the engine. There may be as many as three concentric shafts, rotating at independent

speeds, with as many sets of turbines and compressors. Other services, like a bleed of cool air,

may also run down the shaft.

Diffuser section: - This section is a divergent duct that utilizes Bernoulli's principle to

decrease the velocity of the compressed air to allow for easier ignition. And, at the same time,

continuing to increase the air pressure before it enters the combustion chamber.

Hot section:




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http://en.wikipedia.org/wiki/Frame_of_reference

http://en.wikipedia.org/wiki/Gas_compressor

http://en.wikipedia.org/wiki/Fan_(mechanical)


Combustor or Can or Flameholders or Combustion Chamber — This is a chamber where

fuel is continuously burned in the compressed air.

Turbine — The turbine is a series of bladed discs that act like a windmill, gaining energy

from the hot gases leaving the combustor. Some of this energy is used to drive thecompressor,

and in some turbine engines (i.e. turboprop, turboshaft or turbofan engines), energy is extracted

by additional turbine discs and used to drive devices such as propellers, bypass fans or helicopter

rotors. One type, a free turbine, is configured such that the turbine disc driving the compressor

rotates independently of the discs that power the external components. Relatively cool air, bled

from the compressor, may be used to cool the turbine blades and vanes, to prevent them from

melting.

Afterburner or reheat (chiefly UK) — (mainly military) Produces extra thrust by

burning extra fuel, usually inefficiently, to significantly raise Nozzle Entry Temperature at

theexhaust. Owing to a larger volume flow (i.e. lower density) at exit from the afterburner, an

increased nozzle flow area is required, to maintain satisfactory engine matching, when the

afterburner is alight.

Exhaust or Nozzle — Hot gases leaving the engine exhaust to atmospheric pressure via a

nozzle, the objective being to produce a high velocity jet. In most cases, the nozzle is convergent

and of fixed flow area.

Supersonic nozzle — If the Nozzle Pressure Ratio (Nozzle Entry Pressure/Ambient

Pressure) is very high, to maximize thrust it may be worthwhile, despite the additional weight, to

fit a convergent-divergent (de Laval) nozzle. As the name suggests, initially this type of nozzle is

convergent, but beyond the throat (smallest flow area), the flow area starts to increase to form the

divergent portion. The expansion to atmospheric pressure and supersonic gas velocity continues

downstream of the throat, whereas in a convergent nozzle the expansion beyond sonic velocity

occurs externally, in the exhaust plume. The former process is more efficient than the latter.

The various components named above have constraints on how they are put together to

generate the most efficiency or performance. The performance and efficiency of an engine can

never be taken in isolation; for example fuel/distance efficiency of a supersonic jet engine

maximises at about mach 2, whereas the drag for the vehicle carrying it is increasing as a square

law and has much extra drag in the transonic region. The highest fuel efficiency for the overall

vehicle is thus typically at Mach ~0.85.

For the engine optimisation for its intended use, important here is air intake design,

overall size, number of compressor stages (sets of blades), fuel type, number of exhaust stages,

metallurgy of components, amount of bypass air used, where the bypass air is introduced, and

many other factors. For instance, let us consider design of the air intake.



http://en.wikipedia.org/wiki/Combustor

http://en.wikipedia.org/wiki/Flame_holder

http://en.wikipedia.org/wiki/Turbine

http://en.wikipedia.org/wiki/Afterburner_(engine)

http://en.wikipedia.org/wiki/Nozzle

http://en.wikipedia.org/wiki/De_Laval_nozzle


EX.NO:6 STRIPPING OF TURBOJET ENGINE

AIM:

To dismantle the turbojet engine in a proper sequence.

TOOLS REQUIRED:

¾ *1/4 BS or 12-13 set spanner

10-11 set of ring spanner


C-spanner

Common screw driver

Ball peen spanner

plier and side cutter

PROCEDURE:

1. Loosen the fine nuts using appropriate spanner and r3emove the inlet case from the

accessory case.

2. Loosen the 10 nuts using no 10-11 set of ring spanner and detach air casing from

compressor case.

3. Remove 15 bolts using no 8-9 set spanner. Detach compressor casing from diffuser.

4. Loosen retaining nut with C-spanner and remove centrifugal impeller.

5. Remove front roller bearing and the sleeve.

6. Remove 2 ignition connection and fuel turners from the combustion chamber outer case.

7. Now take out the turbine along with the shaft from the rear side.

8. Take out the combustion chamber.

9. Loosen the bolts and nuts from the exhaust pipe flange and detach the exhaust pipe from

the combustion chamber.

10. Loosen the clamps of the propelling nozzle and disconnect the nozzle from the exhaust

pipe.

11. Keep all the removed parts separately in the cleaned tray in sequence so that there is no

possibility of mixing with each other.

12. Wherever blanking is required, blank it and place identification slips.




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RESULT:

Thus the turbojet engine in dismantled and the components are studied.

VIVA QUESTION:

What is operating principle of jet engine?

What is the temp of air entering the combustion chamber?

How much should be turbine blade tip clearance?

What is compressor recovery wash?




EX.NO:9 ASSEMBLY OF TURBO JET ENGINE

AIM:

To assemble a turbojet engine in a proper sequence.

TOOLS REQUIRED:

¾ *1/4 BS or 12-13 set spanner



C-spanner

Common screwdriver

Ball peen spanner

plier and side cutter

PROCEDURE:

1. Remove all blankings and clean them thoroughly.

2. Attach air intake case front accessory by tightening all the 5 nuts using 12-13 set hammer

3. Attach air intake case rear to the compressor case by tightening all the nuts using 10-11

set ring spanner

4. Now assemble the compressor in the front and turbine at the rear of the shaft by inserting

the shaft in front of the diffuser case.

5. Enclose the combustion chamber outer case over the flame tube and tighten all the 15

bolts.

6. Encage 2 ignition and 5 fuel burners connection and tighten the nuts.

7. Encage the exhaust pipe to combustion chamber outer case flange and tighten all the bolts

and nuts.

8. Attach the propelling nozzle to the rear side exhaust pipe and together with the clamp.

RESULT:

Thus the turbojet engine is assembled as per the maintenance manual instructions.




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VIVA QUESTION:

How does the turbine transmit power to the compressor?

What is interconnectors?

What is two stage turbine?

What is the max r.p.m of a turbine engine?




EX.NO: 10 ENGINE STARTING PROCEDURE

AIM:

To study the starting problem of engine

PROCEDURE FOR PREPARATION:

1. Before starting an engine, aircraft servicing record (ASR) form has to be referred for

knowing the serviceability of both engine and aircraft.

2. The aircraft is to be positioned nose towards the wind.

3. For a piston engine, the wind direction will affect the following

a. Engine speed obtained during checks.

b. Likely to cause vibration in certain directions

4. For turbine engine a/c strong tail wind could result increased jet pipe temp (JPT) during

start.

5. In a turboprob engine if wind rotates propellar in opposite direction of rotation then do

not start the engine.

6. During cold condition before starting piston engine 2 or 3 rotation of propellar should be

given by hand to remove the air.

7. Priming of piston engine cylinder should be carried out if necessary

8. In a piston engine if engine fire develops during starting then continue cracking to start

the engine to blow out the fire.

PRECAUTIONS:

The ground power unit and CO2 fire extinguisher trolley are to be stationed near the a/c.

1. The starting crew should not wear loose clothes.

2. For jet engine during starting performed should not go near to more than 5m from frontal

area and 100m from the tail pipe.

3. All control locks should be removed. The engine cover wheel cover, canopy covers are to

be removed.

4. Visual inspection of the a/c and the engine has to be done to ensure that there are no loose

panels and cowling before starting the ground run.




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5. Only components persons should be given ground run.

PROCEDURE FOR STARTING THE ENGINE

PISTON ENGINE:

1. Turn the auxiliary fuel pump on if a/c is so equipped.

2. Place the mixture control to the piston recommended for the engine and carburetor

combination being started. As a general rule, the mixture control should be in the ‘idle

cut off’ position for pressure type carburetors and in the ‘full rich’ for float type

carburetors.

3. Many light a/c are equipped with a mixture control pull rod which has no defended

intermediate position when such controls are pushed in flush with the instrument panel

the mixture is set in the ‘full rich’ position conversely when the control rod is fulled all

the way out the carburetor is in the ‘idle cut off’ or ‘full bean’ position. Unmarked

intermediate position b/w these two extremes can be selected by the operator to achieve

any desired mixture setting.

4. Open the throttle to a position that will provide 1000 to 1200 rpm.

5. Leave the preheat or alternate air control in the ‘cold’ position to prevent damage and fire

in case of backfire. This auxiliary heating devices should be used of ten the engine warms

up. The improve fuel vaporization, prevent fouling of the spark plug oil formation and

climate icing in the induction system.

6. Energize the starter after the propeller has made at least two compile revolutions and twin

the ignition switch on one engine equipped with on induction vibrator turn switch to the

‘both’ position. When starting on engine; that uses on impulse coupling magnetic turn by

ignition switch to the ‘left’ position. Place the ignition switch to the ‘start’ when the

magnetic incorporation a retard breaker assembly. Do not crank the engine continuously

with the starter for more than 1 minute. Allow a 3 to 5 minute period for cooling the

starter between successive attempts. Otherwise the starter may be burned out due to

overheating.

7. Move the primer switch to ‘on’ intermittently or prime with one or three stokes of

priming pump, depending of on how the aircraft is equipped. When the engine begin to

fire, hold the primer on, while gradually opening throttle to obtained smooth operation.

8. After the engine is operating smoothy on the primer, move the mixture control to the ‘full

rich’ position. Release the primer as soon as drop in r.p.m indicates the engine in

receiving additional from the carburetor.

JET ENGINE:

1. Place the start selector switch to the desired engine and the start arming switch (if so

equipped) to ‘start position’

2. Turn the a/c boost pumps on




3. Place the fuel and ignition switch on

4. Position the low rpm switch in low or normal (high)

5. Make sure that the power lever is in the ‘start’ position: If the propellar is not at the ‘start’

position. Difficulty may be encountered in making a start.

6. Depress the start switch and if printing is necessary depress the primer button.

7. Make sure the fuel pump parallel light comes on at or above 2200 rpm and remains on

upto 900 rpm.

8. Check the oil pressure and temperature maintain the power level at the ‘start’ position

until the specified minimum oil temperature is reached.

9. Disconnect the ground power supply.

RESULT:

Thus the starting procedure of the engine has been studied.

VIVA QUESTION:

What is a need of booster pump?

What equipment is driven from the engine?

How is the maximum r.p.m. controlled?

What is a starting by-pass?



Documents

Ae2355 Manual