SUMMER TRAINING

REPORT

Hindustan Aeronautics Limited

Lucknow, U.P.(Duration: 25st June 2011 to 24th July 2011)

Submitted for partial fulfillment of the requirement for the award of the degree of

Bachelor of Technology

In

ELECTRONICS & INSTRUMENTATION ENGINEERING

SUBMITTED BY:

ABHISHEK PANDEY08EI02

Department of Electronics & Instrumentation Engineering,

I.E.T., M.J.P. Rohilkhand University,

Bareilly(U.P.)-243006

DECLARATION

I here by declare that project work is an authentic record of my own work carried out at

HINDUSTAN AERONAUTICS LIMITED, LUCKNOW as requirement of 4 weeks project

for the award of degree during 25th JUNE to 24th JULY, 2011.

ABHISHEK PANDEY

08EI02

M.J.P.R.U., BAREILLY

Certified that the above statement made by the student is correct to the best of our knowledge

and belief.

Sign._________

INSTITUTE OF ENGINEERING & TECHNOLOGY

M.J.P.ROHILKHAND UNIVERSITY

BAREILLY-243006

CERTIFICATE

CONCERN TO WHOM IT MAY

This is to certify that Mr. ABHISHEK PANDEY, ROLL NO. 08EI02, B.Tech. final year student of Electronics & Instrumentation Engineering had undergone an Industrial Training at “HINDUSTAN AERONAUTICS LTD.” Lucknow, effect 25-06-2011 TO 24-07-2011. He has appeared in the Industrial Training viva–vice as partial fulfillment of requirement for the award of degree in “Bachelor of Technology” in the Electronics & Instrumentation Engineering of M.J.P. Rohilkhand University, Bareilly during the Academic year 2011-12.

Mr. Yatendra Kumar

H.O.D.

(EI Deptt.)

ACKNOWLEDGEMENT

With deep sense of gratitude, first & foremost I express my

profound thanks to Mr. Manoj Kumar, Sr. Manager- Training for giving

me this very opportunity to do my summer training in the Instrument

factory of H.A.L. Lucknow during the summer session- 2011.

I would like to express my gratitude to Mr. Ram Awtar, Head of

Instrument factory, our training guide for the valuable guidance ,

inspiration & enouragenment.

Last but not the least, I also wish to acknowledge my indebteness

to the staff of H.A.L. without whose co-operation, this training would not

have not been successful.

The training at H.A.L. Lucknow was full of responsiveness & it

gave me the rare opportunity to correlate the theoretical knowledge with

the practical one.

Being well known company of India & abroad, it gave me the

opportunity to learn the work carried out here, got a glimpse of new

environment & hard work of industrial unit.

CONTENT

1. Preface

2. About H.A.L.

3. Organizational Growth of HAL

4. Our Products

5. The Organization

6. HAL services

7. Airplane parts definitions

8. Major products of the H.A.L. Division

9. H.A.L. Accessories Division - Lucknow

10. Instrument Factory 

Clean room

Assembly and test shop 2 & 3 

Electromagnetic rotating shop (E.R.M)

Ground land navigation system shop (G.L.N.S)

11. Gyroscope

Properties

12. Actuator

Mechanical actuators

Hydraulic actuators

Piezoelectric actuators

Electro-mechanical actuators

Linear Actuator

Trim Actuator

13. Flight Data Recorder 

14. Advanced Light Helicopter (ALH)

15. Conclusion

16. References

PREFACE

Last few years have witnessed major changes in economic environment of

our country. The industrial and economical policies have been liberalized .Indian

industries have become globally competitive, giving boost to the young and small

enterprises and thus arises the need of an efficient research and development

department.

I had done my part of training in INSTRUMENT DEPARTMENT of HAL

LUCKNOW. The project I had worked on ALH department, SU30 department.

There I had learned a lot of things about Helicopter and Fighter plane.

This all, for me, was a memorable experience.

Hindustan Aeronautics Limited (HAL) came into existence on 1st

October 1964.  The Company was formed by the merger of Hindustan

Aircraft Limited with Aeronautics India Limited and Aircraft Manufacturing

Depot, Kanpur.

The Company traces its roots to the pioneering efforts of an industrialist with

extraordinary vision, the late Seth Walchand Hirachand, who set up Hindustan

Aircraft Limited at Bangalore in association with the erstwhile princely State of

Mysore in December 1940. The Government of India became a shareholder in

March 1941 and took over the Management in 1942.

Today, HAL has 19 Production Units and 9 Research and Design Canters in 7

locations in India. The Company has an impressive product track record - 12 types

of aircraft manufactured with in-house R & D and 14 types produced under

license. HAL has manufactured over 3550 aircraft, 3600 engines and overhauled

over 8150 aircraft and 27300 engines.

HAL has been successful in numerous R & D programs developed for both

Defense and Civil Aviation sectors. HAL has made substantial progress in its

current projects:

Dhruv, which is Advanced Light Helicopter (ALH)

Tejas - Light Combat Aircraft (LCA)

Intermediate Jet Trainer (IJT)

Various military and civil upgrades.

Dhruv was delivered to the Indian Army, Navy, Air Force and the Coast

Guard in March 2002, in the very first year of its production, a unique

achievement.

HAL has played a significant role for India's space programs by participating in the

manufacture of structures for Satellite Launch Vehicles like

PSLV (Polar Satellite Launch Vehicle)

GSLV (Geo-synchronous Satellite Launch Vehicle)

IRS (Indian Remote Satellite)

INSAT (Indian National Satellite)

HAL has formed the following Joint Ventures (JVs):

BAeHAL Software Limited

Indo-Russian Aviation Limited (IRAL)

Snecma HAL Aerospace Pvt Ltd

SAMTEL HAL Display System Limited

HALBIT Avionics Pvt Ltd

HAL-Edgewood Technologies Pvt Ltd

INFOTECH HAL Ltd

 Apart from these seven, other major diversification projects are Industrial Marine

Gas Turbine and Airport Services. Several Co-production and Joint Ventures with

international participation are under consideration.

HAL's supplies / services are mainly to Indian Defence Services, Coast Guards and

Border Security Forces. Transport Aircraft and Helicopters have also been supplied

to Airlines as well as State Governments of India. The Company has also achieved

a foothold in export in more than 30 countries, having demonstrated its quality and

price competitiveness.

HAL has won several International & National Awards for achievements in

R&D, Technology, Managerial Performance, Exports, Energy Conservation,

Quality and Fulfillment of Social Responsibilities.

 HAL was awarded the “INTERNATIONAL GOLD MEDAL AWARD”

for Corporate Achievement in Quality and Efficiency at the International

Summit (Global Rating Leaders 2003), London, UK by M/s Global Rating

and UK in conjunction with the International Information and Marketing

Centre(IIMC).

HAL was presented the International - “ARCH OF EUROPE “Award in

Gold Category in recognition for its commitment to Quality, Leadership,

Technology and Innovation. At the National level, HAL won the "GOLD

excellence in Public Sector Management, instituted by the TROPHY" for

Standing Conference of Public Enterprises (SCOPE). The Company scaled

new heights in the financial year 2006-07 with a turnover of

Rs783.61Crores.

Su

30 MKI

Twin-seater, Multi-role, Long range Fighter / Bomber /

Air Superiority Aircraft

MiG-27 M

Single-seater Tactical Fighter / Bomber with variable sweep

wings

MiG-21 VARIANTS

Single-seater Front line Tactical Interceptor / Fighter

Aircraft

JAGUAR

Stabilized Inertial Platform with Dry-tuned Gyroscopes

and Accelerometers

AIRPLANE PARTS DEFINITIONS

And their functions

This page shows the parts of an airplane and their functions. Airplanes are

transportation devices which are designed to move people and cargo from one

place to another. Airplanes come in many different shapes and sizes depending on

the mission of the aircraft. The airplane shown on this slide is a turbine-powered

airliner which has been chosen as a representative aircraft.

For any airplane to fly, you must lift the weight of the airplane itself, the

fuel, the passengers, and the cargo. The wings generate most of the lift to hold the

plane in the air. To generate lift, the airplane must be pushed through the air. The

jet engines, which are located beneath the wings, provide the thrust to push the

airplane forward through the air. The air resists the motion in the form of

aerodynamic drag. Some airplanes use propellers for the propulsion system instead

of jets.

To control and maneuver the aircraft, smaller wings are located at the tail of

the plane. The tail usually has a fixed horizontal piece (called the horizontal

stabilizer) and a fixed vertical piece (called the vertical stabilizer). The stabilizers'

job is to provide stability for the aircraft, to keep it flying straight. The vertical

stabilizer keeps the nose of the plane from swinging from side to side, while the

horizontal stabilizer prevents an up-and-down motion of the nose. (On the Wright

brother's first aircraft, the horizontal stabilizer was placed in front of the wings.

Such a configuration is called a canard after the French word for "duck").

At the rear of the wings and stabilizers are small moving sections that are

attached to the fixed sections by hinges. In the figure, these moving sections are

colored brown. Changing the rear portion of a wing will change the amount of

force that the wing produces. The ability to change forces gives us a means of

controlling and maneuvering the airplane. The hinged part of the vertical stabilizer

is called the rudder; it is used to deflect the tail to the left and right as viewed from

the front of the fuselage. The hinged part of the horizontal stabilizer is called the

elevator; it is used to deflect the tail up and down. The outboard hinged part of the

wing is called the aileron; it is used to roll the wings from side to side. Most

airliners can also be rolled from side to side by using the spoilers. Spoilers are

small plates that are used to disrupt the flow over the wing and to change the

amount of force by decreasing the lift when the spoiler is deployed.

The wings have additional hinged, rear sections near the body that are called

flaps. Flaps are deployed downward on takeoff and landing to increase the amount

of force produced by the wing. On some aircraft, the front part of the wing will

also deflect. Slats are used at takeoff and landing to produce additional force. The

spoilers are also used during landing to slow the plane down and to counteract the

flaps when the aircraft is on the ground. The next time you fly on an airplane,

notice how the wing shape changes during takeoff and landing.

The fuselage or body of the airplane, holds all the pieces together. The pilots

sit in the cockpit at the front of the fuselage. Passengers and cargo are carried in

the rear of the fuselage. Some aircraft carry fuel in the fuselage; others carry the

fuel in the wings.

As mentioned above, the aircraft configuration in the figure was chosen only

as an example. Individual aircraft may be configured quite differently from this

airliner. The Wright Brothers 1903 Flyer had pusher propellers and the elevators at

the front of the aircraft. Fighter aircraft often have the jet engines buried inside the

fuselage instead of in pods hung beneath the wings. Many fighter aircraft also

combine the horizontal stabilizer and elevator into a single stipulator surface.

There are many possible aircraft configurations, but any configuration must

provide for the four forces needed for flight.

Aircraft Yaw Motion

In flight, any aircraft will rotate about its center of gravity, a point which is the

average location of the mass of the aircraft. We can define a three dimensional

coordinate system through the center of gravity with each axis of this coordinate

system perpendicular to the other two axes. We can then define the orientation of

the aircraft by the amount of rotation of the parts of the aircraft along these

principal axes. The yaw axis is perpendicular to the wings and lies in the plane of

the aircraft centerline. A yaw motion is a side to side movement of the nose of the

aircraft as shown in the animation.

The yawing motion is being caused by the deflection of the rudder of this

aircraft. The rudder is a hinged section at the rear of the vertical stabilizer.

As described on the shape effects slide, changing the angle of deflection at

the rear of an airfoil changes the amount of lift generated by the foil. For the

vertical stabilizer and rudder, the orientation of the airfoil causes a side force to be

generated. With greater deflection of the rudder to the left, the side force increases

to the right. With greater deflection to the right, the side force increases to the left.

The lift generated by the rudder acts through the center of pressure of the rudder

and vertical stabilizer and is located at some distance from the center of gravity of

the aircraft. The change in side force created by deflecting the rudder generates a

torque about the center of gravity which causes the airplane to rotate. The pilot

uses this ability to keep the nose of the aircraft pointed in the direction of travel.

On all aircraft, the vertical stabilizer and rudder create a symmetric airfoil.

This produces no side force when the rudder is aligned with the stabilizer and

allows the combination to produce either positive or negative side force, depending

on the deflection of the rudder. Some fighter planes have two vertical stabilizers

and rudders because of the need to control the plane with multiple, very powerful

engines

Aircraft Roll Motion

.

In flight, any aircraft will rotate about its center of gravity, a point which is the

average location of the mass of the aircraft. We can define a three dimensional

coordinate system through the center of gravity with each axis of this coordinate

system perpendicular to the other two axes. We can then define the orientation of

the aircraft by the amount of rotation of the parts of the aircraft along these

principal axes. The roll axis lies along the aircraft centerline. A roll motion is an up

and down movement of the wings of the aircraft as shown in the animation .

The rolling motion is being caused by the deflection of the ailerons of this

aircraft. The aileron is a hinged section at the rear of each wing. The ailerons work

in opposition; when the right aileron goes up, the left aileron goes down.

As described on the shape effects slide, changing the angle of deflection at

the rear of an airfoil will change the amount of lift generated by the foil. With

greater downward deflection, the lift will increase in the upward direction; with

greater upward deflection, the lift will decrease in the upward direction. Since the

ailerons work in pairs, the lift on one wing increases as the lift on the opposite

wing decreases. Because the forces are not equal, there is a net twist, or torque

about the center of gravity and the aircraft rotates about the roll axis. The pilot can

use this ability to bank the aircraft which causes the airplane to turn.

On this page we have demonstrated an aircraft roll induced by movement of

the ailerons, but there are other ways to produce a rolling motion on an aircraft.

The Wright brothers used a method called wing warping. Their wings were wired

together in such a way that the outer panels of each wing could be twisted relative

to the inner panel. The twisting changed the local angle of attack of sections of the

wing which changed the lift being generated by that section. Unequal forces on the

wings caused the aircraft to roll. Many modern airliners use a spoiler to roll the

aircraft. A spoiler is a plate that is raised between the leading and trailing edges of

the wing. The spoiler effectively changes the shape of the airfoil, disrupts the flow

over the wing, and causes a section of the wing to decrease its lift. This produces

an unbalanced force with the other wing, which causes the roll. Airliners use

spoilers because spoilers can react more quickly than ailerons and require less

force to activate, but they always decrease the total amount of lift for the aircraft.

It's an interesting trade! You can tell whether an airliner is using spoilers or

ailerons by noticing where the moving part is located. At the trailing

edge, it's an aileron; between the leading and trailing edges, it's a spoiler.

(Now you can dazzle the person sitting next to you on the plane!)

MAJOR PRODUCTS OF THE H.A.L. DIVISION

        The major products of the Division are:

Undercarriage systems

Wheels and Brake systems

Hydraulic Systems

Aircraft and Engine Fuel Systems

Panel Instruments (Barometric and gyroscopic)

Electric Power Generation and Control systems

Environmental control systems.

Flight Control Actuators

Ground Support Equipment and test Rigs.

Main Customers:

 

i. Indian Air Force, Army, Navy, Coast Guard, BSF

ii. Defence R&D Laboratories and Deptt of Space;

iii. Civil Aviation, State Govt., Ordnance Factories, Corporate Sectors;

iv. Flying Academies & Educational Institutions;

v. Airlines, Air Taxi, Air Cargo;

vi. Overseas customers for civil and military applications.

vii. Collaborators and Licensors. 

HAL ACCESSORIES DIVISION - LUCKNOW 

Hindustan Aeronautics Limited

Accessories Division

Lucknow 226 016

India

The Division was established in 1970 with the primary objective of manufacturing

systems and accessories for various aircraft, helicopters and engines with a view to

attain self-sufficiency in this field in the country. The Division started with the

manufacture of hydro-mechanical accessories and instruments under license for

Marut and Kiran aircraft. This was followed by license manufacture of accessories

for MiG-21 aircraft, Cheetah/Chetak helicopters, Dornier and other defense

applications. Additionally repair and overhaul of Lucknow manufactured

accessories as well as those fitted on directly purchased aircraft, such as Mirage

and Sea Harrier was undertaken. At present, it is manufacturing, repairing and

overhauling more than 800 different types of systems and accessories under

license. The range of items cover units for hydraulics, engine fuel system,

environment control system, pressurization system, gyroscopic instruments,

barometric instruments, electrical system items, undercarriages, and electronic

items. The number of licensors exceeds twenty. 

         From inception, the Division has laid emphasis on developing indigenous

capability through design and development of various systems and accessories. 

This capability has culminated in indigenous design and development of a variety

of systems and accessories for the Light Combat Aircraft (LCA), Advanced Light

Helicopter (all versions i.e. Army, Air force, Navy & Civil) and Intermediate Jet

Trainer (IJT-36). The Division has also developed and has made successful strides

into the area of Microprocessor based control systems. Design and Development

capabilities include Environmental Control Systems & Pneumatics, Fuel

Management, Engine Fuel Control & aircraft fuel systems, Microprocessor based

Controllers, Hydraulic System & Power Controls, Wheels and Brakes, Cockpit

instruments and sensors, Gyroscopes, Electrical Power Control Protection,

Navigation and Display, Land Navigation, Ground support equipment, Dedicated

Test rigs, and Computerized test equipment. The Division has diversified in other

defence applications like tanks and armored vehicles for Army, and took

commercial applications of Hydraulic items, Gyroscopic Equipment, Special

Purpose Test Equipment & Ground Support Equipment. 

        The Division has also made steady progress in the area of Exports. The range

of products and services available for exports include: 

1. Rotables and spares of Jaguar International and Cheetah (Lama), Chetak

(Alouette) Helicopters;

2. Ground Support Equipment for MiG 23, 27, 29 Mirage-2000, Jaguar, LCA, Su-

30, Sea-Harrier, Dornier DO-228, Avro HS-748, Cheetah, Chetak, MI-17, and

ALH.

3. Repair and Overhaul of aircraft accessories of MiG series, Jaguar International,

Cheetah (Lama), Chetak (Alouette) and Dornier.

The Division today has a prime name in the aviation world and a number of

international companies are interested to join hands with it for future projects. 

H.A.L. accessory division, Luknow is divided into three main factories namely

1. Mechanical Factory

2. Instrument Factory

3.FuelFactory 

 

INSTRUMENT FACTORY  

 This factory deals with the testing and assembly of electronics instruments used in

aircraft e.g. Altimeter, RMI, Gyro-magnetic compass , black box etc. 

This INSTRUMENT FACTORY is further divided into four units which are as

follows: 

CLEAN ROOMS

ASSEMBLY AND TEST SHOP 2 & 3

ELECTRO ROTATING MACHINES

GROUND LAND NAVIGATION SYSTEM SHOP (G.L.N.S Shop)

Clean room

        In Clean room those subunits are assembled and tested that are sensitive to

dust, temperature and humidity. All these parameters are kept under control

because these can have adverse effect on their functional efficiency.

        The required specification for the instruments assembled and tested are

different .so Clean room is further subdivided into three units. The following chart

is given for the classification of clean room. 

 

 

 

 

 

 

STANDARD CLEAN ROOM CONDITIONS: 

 

ROO

M

 

ITEM

 

Temp

Limit

s    °C

 

Humidit

y R/H %

 

Dust Count

Particle size 0.5

m/ft3

 

AIRCRAFT

ROOM

1 

 

 

 

ROOM

2 

 

 

 

 

 

 

 

 

Gyroscopic

Instruments of

Russian Origin 

Barometric

Instruments,

Accelerometers

, RPM

Indicator of

Western

Origin 

 

 

Gyroscopic

Instruments of

Western Origin

15 to

25

° C 

 

 

 

15 to

25

° C 

 

 

 

 

 

 

 

45 -55 

 

 

 

45 -55 

 

 

 

 

 

 

 

 

45 -55

<100,000

CLASS C –

UNMONITORE

D 

<100,000

CLASS B 

 

 

 

 

 

 

 

MIG 21, 27, AN

– 32  

 

 

Kiran MK-I&II,

HPT-32, Jaguar,

AN-32, Mirage,

Dornier, Avro 

Aircraft,

Cheetah,

Chetak, ALH

Helicopters 

Kiran MK-I&II,

HPT-32, Jaguar,

AN-32, Mirage,

ROOM

3

 

15 to

25 ° C

<10,000

CLASS A -

MONITORED

Dornier, Avro 

Aircraft,Lakshy

a, Cheetah,

Chetak

Helicopters

 

Assembly and test shop 2 & 3 

        The major products of H.A.L. are fighter aircrafts. An aircraft comprises of

many small units or accessories, which play significant role in their successful

flight. any fault, may lead to an catastrophic end. Here comes the role of assembly

and test unit .it forms an integral part of any manufacturing unit. The main

instrument were KCN-2 compass system, flight data recorder, gyro magnetic

compass, fuel gauging system, radio magnetic indicator, milli voltmeter

temperature indicator.

Electromagnetic rotating shop (E.R.M)

  In the E.R.M department of the instrument factory the assembly and testing

of the dc Starter Generators, AC Generator system, Constant speed alternator,

Regulators, Inverter, of the Russian and French origin. These products are

basically those products which takes the principle of the electromagnetic rotating

which can be elaborated as follows i.e., electrical energy is converted into

mechanical energy or vice versa. These products are of mig-21 & mig-27 aircrafts

which is of Russian origin and jaguar aircraft is of France origin.   

Ground land navigation system shop (G.L.N.S)

       Ground land navigation system shop is one of the most different & unique

shop. As in this shop it manufacture the only ground land navigation system in

world. As due the different applicability of the gyros therefore these gyro own

s have been placed in the road transportation system which is used in ground e.g.

trucks, cars. The instrument which uses the property of any type of gyro and is

installed in road transportation system is known as ground land navigation system.

The Gyro land navigation system is an electronic navigation device used for

guiding any army vehicle to its destination point. The principle objective of system

is not only to ease the in more precise and quicker manner whether in plains, hills

or sand dunes, where there are no special remarks. In the G.L.N.S shop it

assembles and test the ground land navigation system of Vijayanta tank .

Gyroscope

A gyroscope is a device for measuring or maintaining orientation, based on

the principles of momentum. The device is a spinning wheel or disk whose axle is

free to take any orientation. This orientation changes much less in response to a

given external torque than it would without the large angular momentum

associated with the gyroscope's high rate of spin. Since external torque is

minimized by mounting the device in gimbals, its orientation remains nearly fixed,

regardless of any motion of the platform on which it is mounted. Gyroscope works

in situations when using magnetic compass is not possible at all (as in Hubble

telescope). Due to higher precision it is used to maintain direction in tunnel

mining.

Description

Within mechanical systems or devices, a conventional gyroscope is a

mechanism comprising a rotor journal to spin about one axis, the journals of the

rotor being mounted in an inner gimbals or ring, the inner gimbals’ being journal

for oscillation in an outer gimbals which in turn is journal for oscillation relative to

a support. The outer gimbals or ring is mounted so as to pivot about an axis in its

own plane determined by the support. The outer gimbals’ possesses one degree of

rotational freedom and its axis possesses none. The inner gimbals are mounted in

the outer gimbals’ so as to pivot about an axis in its own plane that is always

perpendicular to the pivotal axis of the outer gimbals’.

The axle of the spinning wheel defines the spin axis. The inner gimbals

possess two degrees of rotational freedom and its axis possesses one. The rotor is

journal to spin about an axis which is always perpendicular to the axis of the inner

gimbals’. So, the rotor possesses three degrees of rotational freedom and its axis

possesses two. The wheel responds to a force applied about the input axis by a

reaction force about the output axis.

The behavior of a gyroscope can be most easily appreciated by consideration

of the front wheel of a bicycle. If the wheel is leaned away from the vertical so that

the top of the wheel moves to the left, the forward rim of the wheel also turns to

the left. In other words, rotation on one axis of the turning wheel produces rotation

of the third axis.

A gyroscope flywheel will roll or resist about the output axis depending

upon whether the output gimbals are of a free- or fixed- configuration. Examples

of some free-output-gimbals’ devices would be the attitude reference gyroscopes

used to sense or measure the pitch, roll and yaw attitude angles in a spacecraft or

aircraft. The center of gravity of the rotor can be in a fixed position. The rotor

simultaneously spins about one axis and is capable of oscillating about the two

other axes, and thus, except for its inherent resistance due to rotor spin, it is free to

turn in any direction about the fixed point. Some gyroscopes have mechanical

equivalents substituted for one or more of the elements, e.g., the spinning rotor

may be suspended in a fluid, instead of being pivotally mounted in gimbals. A

control moment gyroscope (CMG) is an example of a fixed-output-gimbals device

that is used on spacecraft to hold or maintain a desired attitude angle or pointing

direction using the gyroscopic resistance force. In some special cases, the outer

gimbals (or its equivalent) may be omitted so that the rotor has only two degrees of

freedom. In other cases, the center of gravity of the rotor may be offset from the

axis of oscillation, and thus the center of gravity of the rotor and the center of

suspension of the rotor may not coincide.

Properties

A gyroscope exhibits a number of behaviors including precession and

mutation. Gyroscopes can be used to construct gyrocompasses which complement

or replace magnetic compasses (in ships, aircraft and spacecraft, vehicles in

general), to assist in stability (bicycle, Hubble Space Telescope, ships, vehicles in

general) or be used as part of an inertial guidance system. Gyroscopic effects are

used in toys like tops, yo-yos, and Powerball’s. Many other rotating devices, such

as flywheels, behave gyroscopically although the gyroscopic effect is not used.

The fundamental equation describing the behavior of the gyroscope is:

Where the vectors τ and L are, respectively, the torque on the gyroscope and

its angular momentum, the scalar I is its moment of inertia, the vector Ω is its

angular velocity, and the vector α is its angular acceleration. It follows from this

that a torque τ applied perpendicular to the axis of rotation, and therefore

perpendicular to L, results in a rotation about an axis perpendicular to both τ and L.

This motion is called precession. The angular velocity of precession ΩP is given by

the cross product:

Precession can be demonstrated by placing a spinning gyroscope with its

axis horizontal and supported loosely (frictionless toward precession) at one end.

Instead of falling, as might be expected, the gyroscope appears to defy gravity by

remaining with its axis horizontal, when the other end of the axis is left

unsupported and the free end of the axis slowly describes a circle in a horizontal

plane, the resulting precession turning. This effect is explained by the above

equations. The torque on the gyroscope is supplied by a couple of forces: gravity

acting downwards on the device's centre of mass, and an equal force acting

upwards to support one end of the device. The rotation resulting from this torque is

not downwards, as might be intuitively expected, causing the device to fall, but

perpendicular to both the gravitational torque (horizontal and perpendicular to the

axis of rotation) and the axis of rotation (horizontal and outwards from the point of

support), i.e. about a vertical axis, causing the device to rotate slowly about the

supporting point. Under a constant torque of magnitude τ, the gyroscope's speed of

precession ΩP is inversely proportional to L, the magnitude of its angular

momentum:

where θ is the angle between the vectors ΩP and L. Thus if the gyroscope's spin

slows down (for example, due to friction), its angular momentum decreases and so

the rate of precession increases. This continues until the device is unable to rotate

fast enough to support its own weight, when it stops processing and falls off its

support, mostly because friction against precession cause another precession that

goes to cause the fall.

By convention, these three vectors, torque, spin, and precession, are all

oriented with respect to each other according to the right-hand rule.

To easily ascertain the direction of gyro effect, simply remember that a

rolling wheel tends, when entering a corner, to turn over to the inside.

Actuator

A linear actuator is a device that applies force in a linear manner, as opposed

to rotationally like an electric motor. There are various methods of achieving this

linear motion. Some actually convert rotational motion into linear motion.

Types

Mechanical actuators

Mechanical actuators typically convert rotary motion of a control knob or

handle into linear displacement via screws and/or gears to which the knob or

handle is attached. A jackscrew or car jack is a familiar mechanical actuator.

Another family of actuators are based on the segmented spindle. Rotation of the

jack handle is converted mechanically into the linear motion of the jack head.

Mechanical actuators are also frequently used in the field of lasers and optics to

manipulate the position of linear stages, rotary stages, mirror mounts, monometers

and other positioning instruments. For accurate and repeatable positioning, index

marks may be used on control knobs. Some actuators even include an encoder and

digital position readout.[1] These are similar to the adjustment knobs used on

micrometers except that their purpose is position adjustment rather than position

measurement.

Hydraulic actuators

Hydraulic actuators or hydraulic cylinders typically involve a hollow

cylinder having a piston inserted in it. The two sides of the piston are alternately

pressurized/de-pressurized to achieve controlled precise linear displacement of the

piston and in turn the entity connected to the piston. The physical linear

displacement is only along the axis of the piston/cylinder. This design is based on

the principles of hydraulics. A familiar example of a manually operated hydraulic

actuator is a hydraulic car jack. Typically though, the term "hydraulic actuator"

refers to a device controlled by a hydraulic pump.

Piezoelectric actuators

The piezoelectric effect is a property of certain materials in which

application of a voltage to the material causes it to expand. Very high voltages

correspond to only tiny expansions. As a result, piezoelectric actuators can achieve

extremely fine positioning resolution, but also have a very short range of motion.

In addition, piezoelectric materials exhibit hysteresis which makes it difficult to

control their expansion in a repeatable manner.

Electro-mechanical actuators

Electro-mechanical actuators are similar to mechanical actuators except that

the control knob or handle is replaced with an electric motor. Rotary motion of the

motor is converted to linear displacement of the actuator. There are many designs

of modern linear actuators and every company that manufactures them tends to

have their own proprietary method. The following is a generalized description of a

very simple electro-mechanical linear actuator.

Linear Actuator

VL13A4Aircraft – Jaguar

The linear actuator VL13A4 is destined to operate the elevator trim. This actuator

is assembled with two motors and a differential planet gear arrangement which

converts the rotary motion of motor to linear motion. As the motors are

bidirectional it shows the progressive working in both the directions. For normal

working of the unit only, one motor is energized at a time. The second motor is

called the sub motor which works in case of failure of main motor.

Specifications

Nominal Load : 20 Dan

Maximum Load : 40 Dan

Operating Voltage : 18V to 29V

Stroke Length : 44+/-1.25mm

Motor RPM : 25000

Rated current : 0.85 Amp

Power : 5.2 Watt

Trim Actuator

Aircraft – ALH

A set of trim / force feel system(FFS) consists of four actuators namely collective,

pitch, roll and yaw actuator corresponding to the four body axis of the helicopter.

These actuators are electromechanical units interfaced with the mechanical as well

as with automatic flight control system. The conventional mechanical control

leakages in pitch, roll, collective and yaw axis are fitted with one corresponding

trim.

Functions

1.) Engagement/disengagement of anchor point by means of an

electrically operated clutch. This anchor point can be displaced

either automatically or mechanically.

2.) Artificial force feel about the anchor point generating a

predetermined feel force. The artificial feel is proportional to the

displacement in pitch, roll and collective trim actuator as they are

spring based. The force feel is a constant friction in the yaw axis.

3.) Pilot controlled displacement of the anchor point by means of an

electrical motor (manual trim function) or by declutching the

artificial feels.

4.) Automatic displacement of the anchor point so as to maintain the

series actuators around there centre position (auto trim) .

Flight Data Recorder  

Purpose and working:

  System records automatically 6 continuously changing parameters which are: 

Altitude

Engine speed

Aircraft speed

Vertical acceleration

Horizontal acceleration

Turn Angle of stabilizer

 Five single command signal, Eight single command signals superimposed on

Three continuously variable parameters, and timer line to indicate the time on

black and white aero photo film and preserves it in normal and crash conditions for

study and analysis of flight conditions. 

Working:

In this, mechanical motion is converted into electrical signals and then it is

converted in to optical signals,. There is a fixed mirror in the vibrator which moves

accordingly to the moving light beam. The light beam is moved under the effect of

a permanent magnetic field and flux and shifts the light beam accordingly. Now

the mirror will move and thus light will move and thus further the photographic

film is printed. 

ADVANCED LIGHT HELICOPTER (ALH)

Advanced Light Helicopter is a multirole, multimission helicopter designed

& developed by HAL. The design of this 5.5-ton class, twin-engine helicopter

incorporates several state of the art technologies. Extensive use of composites high

cruise speed, long range & endurance, excellent high altitude performance and

capability to operate in hot & humid environment are the key design features. ALH

has been designed for both civil & military applications in large variety of roles

overland & sea.

Performance:-

Maximum cruise speed at maximum load : 250 km/hr

Maximum rate of climb : 10 m/sec

Range with 20 min reserve : 650 km

Endurance : 4 hrs

Hover in ground effect : 1500 m

Hover out of ground effect : 1000m

Leading Particulars:-

Overall length : 15.87 m

Overall height : 4.91 m

Width : 3.19 m

Empty weight : 2500 kg

Fuel capacity : 1100 kg

Maximum take-off weight : 5500 kg

Maximum under slung weight : 1500 kg

Maximum height : 25000 HT

Roles:-

Military Role( unarmed):-

Heliborne attack

Reconnaissance

Logistics support

Casualty evacuation

Air observation post

Military Role (Armed):-

Anti tank

Close air support

Anti submarine warfare

Anti surface vessel warfare

Civil Role:-

Commuter / VIP

Search & rescue

Disaster relief

Air ambulance

Offshore operations

Salient Features:-

Ergonomically designed cockpit

Extensive use if composites, reduced radar signature

Large cabin volume

Ballistic damage tolerant

Greater system redundancy

Provision for weapons hard points

Twin engine with full authority digital electronic control

Adequate safety margin for single engine operation

Four axes automatic flying control system

Crash worthy crew seats, under floor & fuel tank

Hinge less main rotor & bearing less tail rotor

Excellent handling qualities at low as well as high speeds

Low maintenance cost & high fuel efficiency

CONCLUSION

Finally we may conclude that HAL Accessories Division, Lucknow is a

Government undertaking, which is entitled to perform the making of the

accessories used in the fighter aircraft.

Although the whole assembly of the aircraft is not done in HAL Lucknow

but there are plans to launch Sukhoi’s full assembly in HAL Lucknow

Thus HAL Lucknow would be entitled to work on latest technology of

Sukhoi aircraft in the coming future.

References

1. http://www.grc.nasa.gov/WWW/K-12/airplane/airplane.html

2. http://www.alibaba.com/countrysearch/IN-suppliers/Alternator_Manufacturers.html

3. http://en.wikipedia.org/wiki/Gyroscope

4. http://www.aircraftspruce.com/menus/ps/oxygensystems.html

5. en.wikipedia.org/wiki/Actuator

6. en.wikipedia.org/wiki/Voltage_regulator

Hindustan Aeronautics Limited

Accessories DivisionLucknow-226 016

India