Mirage Aircraft Basics PDF

RESTRICTED CHAPTER - 1 BASICS PART - I Introduction 1. BASICS stand for Basics aircraft system introduction and concerning safeties. This chapter provides core information for all Mirage aircraft technicians. It covers the Gen...

RESTRICTED CHAPTER - 1 BASICS PART - I Introduction 1. BASICS stand for Basics aircraft system introduction and concerning safeties. This chapter provides core information for all Mirage aircraft technicians. It covers the General information about Mirage-V PA aircraft that is to include aircraft description, an overview of aircraft systems, aircraft inspection and other related topics. The chapter also touches on the subject of aircraft safety and organizational level maintenance. Mirage Aircraft Aircraft General Information 2. Mirage-V PA is single seater, single engine, delta wing and all weather Mach 2 aircraft, manufactured by DASSAULT. It is basically a low altitude strike aircraft, but it can also be used as a day fighter. The aircraft cockpit is air conditioned, pressurized, and is equipped with a Martin Baker ejection seat. The seat is designed for ejection at ground level provided the aircraft speed equals to or exceeds 90 Knots. Operation 3. In normal use with external stores, aircraft operation requires 4920 to 9840 ft (1500 to 3000 m) hardened runways, according to aircraft configuration. Performance 4. The aircraft performance is as follows:- (a) Max speed below 33000 ft = 750 Knots (Clean aircraft) 1 RESTRICTED  RESTRICTED (b) Max speed above 33000 ft = 2 Mach (Clean aircraft) (c) Operational Ceiling Height = 50000 ft (d) Maximum Endurance with full Internal and external fuel = 03 hours (e) Inverted Flight duration = 15 Seconds. Aircraft Dimensions 5. (a) Length (with pitot tube) = 51.05 ft Length of Mirage Aircraft (b) Span (wing to wing) = 26.97 ft Wing Span of Mirage Aircraft (c) Height (clean aircraft with full internal fuel) = 14.76 ft (d) Track = 10.33 ft (e) Nose Wheel Turning Radius = 60 deg 2 RESTRICTED  RESTRICTED Nose Wheel Turning Radius of Mirage Aircraft Aircraft Weight 6. The weight of the aircraft is: - (a) Empty = 14,990 Lbs. (b) Take –Off weight = 21,150 Lbs. to 29750 Lbs. (Varies with configuration) Fuselage 7. The fuselage is of conventional monocoque construction and complies with the area rule in that, it has a ‘Wasp Waist”. Its main points are frames 20, 26 and 32, that receive the wing spar and fuselage pylon attachment points. Frame 33 receives the main fin spar attachment point. Frames 2 and 10 limit the cockpit. (a) Nose Cone The Nose Cone houses the following: - The radar ranger - The air data computer - The auto-command box - The low-altitude safety box - The TACAN system - The radio-altimeter - The inertial unit - The altitude unit - The sight electronics box - The DC/DC converter (inertial unit) - The servo-control box - The platform adapter box - The load setting box 3 RESTRICTED  RESTRICTED The cone skin is constituted by a polyester radome. The nose cone is secured to frame 1 at four points. (b) Air intake ducts. The side air intakes are provided with a boundary layer bleed. The bled air is partly channeled into the fuselage and is used for cooling the jet engine and for supplying ram air to the heat exchangers in to conditioning system. The air intakes are fitted with moving shock cones, better known as ‘Mice’. The mice start moving forward at Mach 1.25 and their displacement follows a law related to the Mach number so that the air intake ducts operate at their best efficiency at all times. The air intake ducts joins together just in front of the engine at mid fuselage. However, they remain separated by a central bulkhead. (c) Bays. The fuselage includes:- (i) A front bay (forward of the main wheel well) which accommodates a gun pack carrying 2X30 mm guns and their ammunition containers (125 shells per gun). (ii) A rear bay which accommodates a 913 Lbs (545 Ltrs) non- jettison able fuel tank. (iii) A front upper bay which accommodates a 779 Lbs (465 Ltrs) fuel tank. The oxygen cylinders and the negative-G flight accumulator are housed in the rear section of this bay. (iv) A bay under the cockpit. (v) Two small heat insulated bays at the lower part of the fuselage between frames 33 and 35. The RH bay houses the bomb release interval meter and the LH bay houses the UHF transmitter receiver. (vi) Three U/C Wells: The nose U/C well gives access to a large number of the air conditioning system or flight control components. The battery is located aft of this well. The main U/C wells give access to certain components of the hydraulic and fuel system. (d) Aircraft Accessory Gearbox. Fitted in a compartment located between the main U/C wells, it consists of a gearbox driven by the engine through a telescopic shaft. The gearbox drives:- (i) Alternator (ii) Generator (iii) Hydraulic pump No 2. 4 RESTRICTED  RESTRICTED (e) Ground Power Receptacles. The following connectors are provided:- (i) The external ground power connection is located at centre of the LH wing root. It is blanked by a manual-locking door. When the door is not closed, a red ‘GRD CONN’ light is illuminated. It includes:- (A) A DC ground connector (B) An AC ground connector. (ii) The tele-briefing connector, near the LH wing trailing edge, with a spring–loaded door. (iii) The ground ventilation connection in the nose cone. (f) Tail Fairing. The tail fairing is the fuselage rear most component and can be easily removed for engine removal. Its upper part includes the brake chute housing. Wing 8. The wing unit is of the delta type, the main characteristics are as follows:- (a) Wing surface area - 374.5 sq.ft (34.8 sq.m) (b) Leading edge sweep back - 60º 36’ (c) Thickness to chord ratio - 4.5 to 3.5% (d) Dihedral - -1º (e) Wing loading - 54.3 to 79.9 Lbs. per sq. ft (f) The wing is of the multi-spar structural box type. The space between the two main spars constitutes an integral fuel tank. Each wing includes:- (i) An outboard and inboard elevon, practically integral with each other. (ii) An inboard control surface. (iii) An airbrake comprising of an upper surface flap and a lower surface flap mechanically lined together. (g) The aircraft has no landing flaps. 5 RESTRICTED  RESTRICTED (h) The leading edge has a conical camber and can be considered as lying on the surface of a cone which has its apex at the wing root. This type of aerofoil improves the aerodynamic behavior at high angle of incidence and particularly increases the maneuvering margins and limits. (j) The leading edge internal section from the wing root to the wing notch fence and front spar of wing constitutes and integral fuel tank. (k) The wing is fitted with notch fences. Located at 53% of the spar. These have the same effects as boundary layer fences. Fin 9. The fin is swept back and its main characterizers are as follows: (a) Leading edge sweep-back - 63 (b) Thickness to chord ratio - 4 to 3.5% (c) It carries the following components:- (i) The UHF fin tip antenna under a fiberglass fairing. (ii) The flux valve between two ribs. Undercarriage 10. The undercarriage is retractable tricycle type:- (a) Wheel track - 10.33 ft (3.15m) (b) Wheel base - 15.94 ft (4.86m) (c) Three wheels are fitted with relatively low pressure tubeless tyres:- (i) Nose wheel - 113 PSI Michelin tyres (according to (ii) Main wheels - 199 PSI Michelin tyres A/C loading) (d) The 3 shock absorbers contain hydraulic fluid and are inflated with nitrogen. (e) Special marks provide for visual checking of the nose shock absorber inflation. (f) The nose undercarriage is connected to its shimmy damper by means of torque links which has to be disconnected before the aircraft towing. 6 RESTRICTED  RESTRICTED Drag Chute 11. The nylon drag chute is of the cruciform type. It is housed inside a container closed by a cap and this cap is also used as an extractor. The container and the mechanism are housed in the fairing above the tail fairing. The drag chute is controlled through the ‘DRAG CHUTE’ lever. Moving the lever aft opens the chute; returning the lever forward releases the chute. The linkage of the chute mechanism is mechanical. The hook jaws are normally in the open position in order to allow for separation from the aircraft in case of inadvertent opening of the brake chute. They are closed by the chute strap only when the chute control lever is placed in the ‘OUT’ position. The maximum speed at which the brake chute may be deployed is 210 knots. Flight Controls 12. The flight controls are powered by two hydraulic systems, with an emergency system as a standby. The controls are irreversible incorporated with an artificial feel unit. The Control surfaces consist of:- (a) Elevons for pitch and roll control. (b) In board control surfaces for pitch control and to function as pitch damper. (c) The rudder for yaw control. (d) A unique feature is the absence of the horizontal stabilizer. To improve aircraft handling special devices have been added to the aircraft flight control system. These are:- (i) An electrically operated Auto Command System, which improves pitch control throughout the flight envelope. (ii) An Altitude Monitor, Connected to the Auto Command Unit, which keeps the aircraft flying at a constant height. (iii) The Roll Stabilizer, which maintains the heading. (iv) The Pitch and Yaw Damper to prevent oscillations under certain flight conditions Engine 13. (a) Introduction The aircraft is powered by an ATAR 09C jet engine manufactured by SNECMA. 7 RESTRICTED  RESTRICTED (b) The exhaust nozzles of ATAR 09C engine are fully variable. The air intake ducts, though not a part of the engine, are an integral part of the power plant system. The air intake ducts include shock cones (commonly known as “Mice”). The essential purpose of the sock cones is to improve engine efficiency at high mach numbers by generating oblique shock waves clear of the intake lips. (c) The engine start up does not require any external power source. A ground power unit is however, used for supplying aircraft services (50 Amps 28 Volts DC) during the engine start up. (d) The aircraft battery supplies the starting current (200 Amps) to the starter directly. The starter consists of a small engine housed in the ATAR engine front fairing and acts as a gas generator. The exhaust gases drive a free turbine coupled to the engine rotor through a reduction gear (a free wheel drive). ATAR 09C Engine Systems 14. (a) After Burner System. (i) There is no After Burner (A/B) operating limitation, either in the air or on ground. (b) Over Speed System. (i) Automatically cuts in when the total air temperature is greater than 27°C at 30, 000 ft or higher altitude. (ii) Can be selected for takeoff, for one minute the thrust increase being 3 to 6 percent. 8 RESTRICTED  RESTRICTED 15. Operation Limitations. LIMITS OF TEST BENCH THRUST ‘F’ SPEED SETTING RPM ‘N’ TEMP T- 4 ºC (lbs) 8650± 50 a. Max with A/B & over speed 14000 715 103 ± 0.6% b. Max with A/B & without over 8400± 50 13232 700+5-10 speed 100± 0.6% 8400±50 c. Max without A/B & over speed 9480 700+5-10 100± 0.6% 2900±100 d. Idling 265 500 34.7±1.2% Major Assemblies 16. (a) Compressor. (i) Type = Axial Flow (ii) No of stages = 09 (iii) Direction of rotation = Clock wise (From Rear) (iv) Compression Ratio = 5.5 : 1 Compressor (b) Combustion Chamber (i) Purpose: Provides space for burning (ii) Type: Annular 9 RESTRICTED  RESTRICTED (c) Turbine (i) Purpose: Extracts energy from gases to drive compressor (ii) Type: Axial flow reaction type (iii) No of stages: 02 (A) 1st turbine wheel (73 blades) (B) 2nd turbine wheel (50 blades) Turbine Assembly Combustion Chamber (d) Jet Pipe (i) Location. At the end of the engine. (ii) Purpose. Provides the area to burn fuel for A/B operation and conveys the gases to nozzle assembly. (iii) Parts. (A) Junction section (B) Nozzle support (C) Nozzle Assembly Jet Pipe 10 RESTRICTED  RESTRICTED Danger Zone 5. (a) Front - 23 Feet Radius (b) Rear with jet deflector - 81 Feet (c) Rear without jet deflector - 195 Feet Danger Zone Area Electrical System 14. The aircraft electrical system comprises:- (a) A DC system with two power sources, a battery and a generator. (b) An AC system powered by an alternator. (c) Some of the important particulars of the aircraft electrical power generating equipment are as follows:- (i) DC Generator = 28.5 Volt, 9 KW DC Generator 11 RESTRICTED  RESTRICTED (ii) AC Generator = Three Phase, constant speed, 10 KVA, 115/200 Volt, 400 CPS. AC Generator (iii) Nickel Cadmium Battery = 24 Volts, 40 A.H. Aircraft Battery (d) External ground power connection is located at the centre of the LH wing root. It has a DC ground connector and an AC ground connector. Connecting of the external power sources automatically cuts out the corresponding aircraft generation system, except for the aircraft battery which remains connected to the battery bus. Cockpit 15. The Mirage aircraft cockpit accommodates a single fighter pilot for its mission. DP (Dual Purpose) aircraft can house two pilots in tandem (one behind the other). The Mirage–V PA cockpit is limited: (a) At the front & back - By frame 2 & 10 (b) At the top - By the hinged canopy & the windshield (c) At the lower part - By the cockpit floor 12 RESTRICTED  RESTRICTED (d) The cockpit side sections consist of the fuselage structure. (e) Cockpit Equipment: The cockpit is provided with many items of equipment installed at the following locations:- (i) Front instrument Panel (ii) Left Hand and Right Hand Consoles (iv) Side Panel 13 RESTRICTED  RESTRICTED Canopy 16. The canopy forms the cockpit upper structure and is located immediately behind the windshield. It is hinged on top of frame 10, is jettisonable and provides access to the cockpit. The canopy consists of a dome 1 fixed in a metal framework. (a) Canopy Operation. The canopy is fully mechanically operated. The canopy is unlocked. (i) From Inside. by means of a lever located on the RH side of the cockpit. (ii) From Outside. by means of a spanner engaging a square drive located on the LH side of the cockpit. (iii) Procedure. The canopy is opened using the action of two bungee cords which bring the canopy to a stable balanced position. The pilot then only has to lock the canopy in the open position by slightly pushing it upward. The canopy is closed by pulling back the canopy control lever on the RH side of the cockpit, which results in unlocking the canopy which re-turns by itself to the stable balanced position. The canopy is then to be pulled fully down with the left hand by means of the canopy handle (21) (para. 1.2) and locked in the down position by pushing the canopy control lever 6 forward. Armament Loads 17. The aircraft has seven ‘external stores’ attachment point. Three are under the fuselage and two under each wing. (a) Under Fuselage. (i) One permanently installed gun pack with 30 mm guns type 552A DEFA. Each gun can fire 125 rounds each. (ii) One in the center line of fuselage non jettisonable PM3M6 pylon is installed. It carries either configuration of bombs. (A) 2X500 Lbs Bombs (B) 2X750 Lbs Bombs (C) 2X1000 Lbs Bombs (D) 2XDurandal Target Penetration Bombs (E) 2XCluster Bombs (F) 2XBDU (For practice bombing) (G) 2XAdapter 65 (For practice bombing) 14 RESTRICTED  RESTRICTED (iii) Two JATO points where non jettisonable CLB 11 pylon are installed which can carry 2X500 Lbs. (b) Under Wings (i) Inner Station (LH & RH) (A) RPK-16 (Bomb + Fuel) carrier is installed which can carry (4X500) or (2X750) or (2X1000) Lbs bombs. (B) JL 100 rocket launcher each carrying 18 rockets with diameter of 68 mm. (ii) Outboard Station (LH & RH) (A) Aim 9P sidewinder or MATRA R550 missile are installed. Fuel Load 18. The aircraft carries JP-8 fuel in Internal and External tanks. There are nine internal tanks with a total capacity of 5762 Lbs. or 3450 Liters. The External tanks can be carried under the wings and the fuselage (a) Under Fuselage. One center line jettisonable tank under the fuselage of 1100 and 1300 liters (2178 Lbs) capacity. (b) Under Wings. Two under wing tanks, one under each wing capacity of:- (i) 1300 liters (2178 Lbs) jettisonable or. (ii) 1700 liters (2848 Lbs) jettisonable or. (iii) 500 liters (838 Lbs) Super Sonic Tanks non jettisonable. (c) The maximum fuel load with full internal and external tanks can be 8150 liters or 13636 Lbs. Instrumentation 19. In Mirage different types of instruments are used to get information on aircraft flight status and functioning of aircraft systems. The systems handled by Instrument trade on Mirage aircraft are as follows: - 15 RESTRICTED  RESTRICTED (a) Flight Instruments. Includes altimeter, ASI/Machmeter, vertical speed indicator and cabin altimeter. These instruments provide altitude, speed, vertical climb and dive of the aircraft along with cabin altitude. (b) Engine Instruments. Includes tachometer and EGT indicating system, which shows the instantaneous speed of the engine and temperature of Jet engine exhaust gases coming out from engine respectively. (c) Fuel Instruments. Includes fuel quantity indicating system, which shows quantities of fuel in the LH and RH fuselage and also the quantity of fuel remaining in the tanks. The fuel consumption indicating system indicates the instant rate of fuel flow to the engine. (d) Hydraulic Instrument. For indicating the pressures of the aircraft hydraulic system. (e) Gyro Instruments. Includes Artificial Horizon, and Vertical & Azimuth Reference System which provides roll and pitch indications relative to earth’s horizon and roll, pitch and heading information respectively. (f) Oxygen System. The oxygen system of Mirage-V aircraft is designed to store and supply oxygen under maximum safety conditions in all the possible missions of the aircraft. Oxygen system consists of two systems Normal oxygen and Emergency oxygen systems. The system normally supplied from two cylinders through regulator assembly. In case of exhaustion of normal cylinders or pilot ejection emergency supply bottle provide oxygen to the pilot. This system can provide oxygen with mixed air or pure oxygen according to the selection and height of the aircraft. (g) Flight Control System. To improve aircraft handling, special devices have been added to the aircraft flight control system these are: (i) Pitch and Yaw damper. Used to prevent oscillations under certain flight conditions. (ii) Auto Command System. Electrically operated auto command system improves pitch control through out the flight envelope. (iii) Altitude Monitor System. Connected with Auto command system when engaged keeps the aircraft flying at a constant height. (iv) Roll stabilizer System. When engaged maintains the heading of the aircraft. (v) Aerodynamic Reference System. Detects various conditions under which an aircraft flies ie various speed, altitude, impact temperature. The Aerodynamic Reference system than provides this information to the concerned aircraft systems and the equipment in the shape of electrical values for applying compensations. 16 RESTRICTED  RESTRICTED Versions of Mirage Aircraft 20. The MIRAGE aircraft were inducted into PAF operation over a period of time. First of the series came in 1967. Since then, different versions of these aircraft which includes FRENCH , AUSTRALIAN & LIBYAN got inducted with time to time. Some of the older versions were also later on modified to new versions to enhance the PAF capability. Avionics Radar Trade 21. The Radar trade of Mirage aircraft looks after following systems. (a) INAS. (Inertial Navigation & Attack System) LW33A/A-1. It serves as the primary navigation and air to ground weapon delivery system as well as provides primary attitude and heading reference for the Mirage-V aircraft. (b) Agave Radar. It is X band airborne radar used in the following modes. (i) In ‘air to sea’ mode for search acquisition and tracking surface target. (ii) In ‘air to air’ mode it is used for search acquisition and tracking of aerial targets. (iii) In ‘air to ground’ mode it works as a precession range finder. (iv) In close air to air combat mode it works as a range finder too. It is also called gun emergency mode. (v) Ground map display mode. This mode is obtained when no selection is made. (vi) Range scales of Agave radar are 12, 25, 40 and 80 NM maximum (148 KM) (c) HUD (Head Up Display). The HUD has been designed for installation in Mirage-V aircraft. It displays luminous images, superimposed on the outside world to the pilot. The pilot sees the firing markers and flight directors while looking through the combining glass. (d) IFF/JZ/YD-126. It provides the controller identification between friend or foe and self-identification feature. Also transmits the emergency signal. 17 RESTRICTED  RESTRICTED (e) TACAN AN/ARN 130(V). It is tactical air navigation system. It consists of a fixed ground beacon and an airborne TACAN system. The two subsystems operate together to from a Radio Navigation system. This system provides the pilot range and bearing from a particular selected ground beacon. In addition to supplying range and bearing information the beacon identify it self every 37.5 sec with ID Tone. (f) AVTR (Airborne Video Tape Recorder). It is essentially a video recorder using video cassette tape of 30 minutes recording. The mission performance is recorded through the AVTR. Avionics Radio Trade 22. The Radio trade in the Mirage-V aircraft looks after the following systems. (a) UHF Communication System. UHF communication system provides communication between pilots and ground controller and other agencies. Different types of Mirage use different type of UHF communications systems. Following communications system are in use for Mirages. (i) V/UHF Communication R&S. It is most common UHF communication set installed on all Mirage aircraft. (b) Intercomm System. It is used to provide communication between front and rear cockpit in Dual seater aircraft. Mir-III DP, DA,DF and DPA2 are the Double seater version of Mirage in PAF. Inter phone system TFAP-12 is being used on all double seater except Mir-III DPA2. Features of intercom system TFAP-12 are as follow. (i) Inter communication between two pilots. (ii) Selection of Radio for transmission. (iii) Routing /mixing /Amplification of all received. Audio including future warning device audio. (c) Telebriefing System. It is an inter communication system between cockpit and ground crew. Pilot or he crew in the cockpit can talk by selecting Tele briefing from intercom control panel and by pressing the press to talk switch, while the ground crew microphone is permanent hot. A receptacle connector ‘IR’ in the fuselage of aircraft enable the ground crew to connect his Telebriefing set TT 644 through a 66Ft long cable. This cable automatically disconnects when the aircraft rolls off. (d) Radio Altimeter AHV6-311. The radio altimeter provides accurate altitude of aircraft with respect to ground/sea. It works on the principle of FM- CW-Radio altimeter and provide altitude information of 0 to 10,000 Ft. Indicator of AHV6-311 provides height information up to 2500 Ft , while the 18 RESTRICTED  RESTRICTED HUD displays height up to 10,000 ft. Beside displaying height on indicator and HUD it also provides altitude information to INAS. Radio Altimeter AHV6-311 is installed on Mir-V PA, PA2, PA3, DPA2 and Mir-III RP2 aircraft. (e) GPS-296. The GPS is a satellite based navigation system, which provides precise position, velocity and time information. The heart of the system consists of 21 satellites cycling around the earth twice in 24 hours. These satellites are distributed among six orbits, approximately 10.900 nautical mile above the earth. The GPS 296 receives data up dates from satellites and provides following basic information. (i) Position ( Longitude – Latitude ). (ii) Velocity ( Speed – range etc ). (iii) Time. Many other informations are calculated and displayed on GPS-296 by using data of basic information. LIFE SAVING EQUIPMENT 24. LSET trade look after the followings:- (a) Parachute: It is installed on the ejection seat and forms the back rest of the pilot seat. The removal and installation is accomplished by LSET tradesmen. Horse shoe type parachute with canvas pack used with PRM-4 ejection seat in Mir V A/C:- (i) The standard Irvin type canopy is used in this parachute having a diameter of 7.3 M (24 Ft). (ii) Safe opening speed of parachute is 250 knots at zero altitude. 19 RESTRICTED  RESTRICTED (iii) The greater part of the canopy is stowed above the arc of horse shoe. An auxiliary parachute is attached with main canopy. (iv) An automatic deployment of canopy is effected by means of an extension line attached with main drogue, which pulls out the pack closure pin and extracts the canopy from pack. (v) The upper part of canopy is called apex and the lower part of canopy is called periphery. (vi) Harness assembly is attached with parachute with the help of this assembly pilot remains securely held with the seat during flying in ascending, descending or inverted flight. (b) Drogue Chute: The Following parachutes make up the duplex drogue stabilizing system. A small controller drogue chute diameter: 22″ and stabilizer drogue chute diameter: 5′ feet. It is used to stabilize the pilot and seat after ejection. It is installed in the container of ejection seat PRM-4 which acts as a head rest for the pilot. (c) Survival Pack: It is also installed on the ejection seat and forms the seat cushion. Survival Pack (i) Outer Envelope. The outer envelope is made up with blue “Edsanyl” nylon canvas panels sowed to form cross. The wide panel end carries a ring and opposite panel carries a cone plate and safety ring. The other two panels carry a 1.5 mm dia. Wire closing piece. pin, closes the outer envelope. (ii) Survival Pack Case. The case is made of yellow orange canvas closed at the bottom by four flaps. The flaps are provided with an eyelet through which a nylon thread R-707 E is threaded for closing the flaps. Expending strap pocket is sewed on left side and two kits are housed inside it. 20 RESTRICTED  RESTRICTED (iii) Cushion. This is made of vegetable fiber and separates the occupant from the survival pack. (iv) Attachment Line. This line is attached by a loop to the CO2 bottle and has a spring hook on the opposite end which is attached to the cylinder inflation head assembly, further attached with expending strap hook. (d) Drag Chute: The drag chute recovery from runway and its subsequent packing is done by the LSE shop. The removal and installation of drag chute is done by crew chief. Drag Chute Assembly (i) Used to reduce the speed of aircraft on landing and to minimize the use of mechanical brakes. Directional Orientation & Notices 24. For description purpose, the following directional orientations are used throughout this volume. (a) Forward. The end of the installed components toward the forward end of the aircraft. (b) Aft. The end of the installed component toward the rear end of the aircraft. (c) Left. The side of the installed component to the left as viewed while standing behind the aircraft facing forward. (d) Right. The side of the installed component to the right as viewed while standing behind the aircraft facing forward. (e) Clockwise/Counterclockwise. Directions of rotation as viewed while standing behind aircraft facing forward. (f) Other Notices. Warnings, Cautions and Notes as used in this precis, are defined as follows:- 21 RESTRICTED  RESTRICTED WARNING An operating or maintenance procedure, practice, condition, statement, etc., which, if not strictly observed, could result in injury to, or death of personnel. CAUTION An operating or maintenance procedure, practice, condition, statement, etc., which, if not strictly observed, could result in damage to, or destruction of, equipment or loss of mission effectiveness. NOTE An essential operating or maintenance procedure, condition, or statement, which must be highlighted. 22 RESTRICTED  RESTRICTED CHAPTER 1 BASICS PART-II Composition of Maintenance Inspection 1. Composition of maintenance inspections are as follows:- (a) Routine Servicing Inspection (i) The routine servicing are primarily the maintenance operations carried out on Pre, Post & Thru flight inspection and weekly inspection. (ii) The Pre flight inspection includes all the operations, which are referenced as J and AVV in the chapter of list of operations on aircraft in General information Book. It might be performed before the first flight of the day and is valid for 24 hours. (iii) Thru flight inspection includes all the operations referenced as AVV. (iv) Post flight inspection includes all the operations referenced as APV. (v) Weekly inspection includes all the operations referenced as ‘H’. It is valid for a week. (b) Basic Maintenance Inspections. These inspections composed of:- (i) The V1 or R1 type insp include the operations referenced V1 or R1. (ii) The V2 or R2 type insp including the operations referenced V2 or R2 V1 or R1 and H. (iii) The V3 type insp including the operations referenced V3, V2, V1 & H. (iv) The R3 type insp including the operations referenced R3, R1 & R2. 23 RESTRICTED  RESTRICTED (c) Minor Maintenance Inspections. These inspections are composed:- (i) The P type inspection including the operations referenced P plus the basic maintenance operations referenced V1 or R1, V2 or R2, V3 or R3 and H. (ii) The P* type inspection including the operations referenced P* plus all the operations of lower periodicity referenced P, V1 or R1, V2 or R2, V3 or R3 and H. (iii) The 2P type inspection including the operations referenced 2P, plus the operations P type inspections referenced P, V1 or R1, V2 or R2, V3 or R3 and H. (iv) The type P*S inspection includes the operation referenced as 2P along with the P* type inspection. (v) Operations referenced P/F – P*/F. (vi) The operations so referenced are in relation with the aircraft flight hours. Therefore, they are to be performed during the dated inspection nearest to the limits given below:- (A) 500 flight hours for P/F inspection. 24 RESTRICTED  RESTRICTED (B) 1000 flight hours for P*/F inspect. (These limits are mandatory and must not be exceeded). (C) These limits are mandatory and must not be exceeded. (d) Maintenance Cycle. This cycle is determined through minor maintenance inspection (P type inspection) to be performed during the scheduled maintenance inspection with a maximum of 24 months. A 500 ‘flight hours limit’ is associated to this periodicity. The first limit to be reached prevails on the second. After a periodic inspection, (P type inspection), the new maintenance cycle could be starts on the first day after the aircraft has been released from the inspection. (e) Inspection Schedule. The maintenance cycle described in the table below has been planned in accordance with an average operational rate < 15 hours per aircraft per month (computed on the flying aircraft). 0 R3 P R2 R2 R1 R1 4 Months 4 Months 4 Months 4 Months 4 Months 4 4 Months or 65 Hrs or 65 Hrs or 65 Hrs or 65 Hrs or 65 Hrs Months or 65 Hrs or 65 Hrs 24 Months Max (i) Basic Maintenance Inspection. The R1-R2-R3 inspection are known as the basic maintenance inspection in the French technical manual. These inspections are performed with a 4 months or 65 flight hours cycle, which ever comes first. (ii) Minor Maintenance Inspections. The ‘P’ inspections are known as minor maintenance inspection in the French technical manual. These inspections are performed as per the following sequence with a maximum periodicity of 24 months. In order to provide the best possible spacing of the aircraft successive entries into major maintenance, the last P & P* S. minor maintenance inspections can be performed after 30 months instead of 24 months. In such a case, after 24 months one R2 type inspection is to be performed INTERVAL ACCUMULATED INSP TYPE 25 RESTRICTED  RESTRICTED 2 YEARS 2 YEARS P 2 YEARS 4 YEARS P* 2 YEARS 6 YEARS 2P 2 YEARS 8 YEARS P* 2 YEARS 10 YEARS P 2 YEARS 12 YEARS P*S (iii) Major Inspections. The major inspections are GV1 and GV2. These inspections are carried out at Mirage Rebuild Factory Kamra. The total sequence of inspection is as shown below: 0 GV1 GV2 2P P* P P*S P P* 2P P* P P*S P P* 12 YEARS -1+2 OR 1500 FLT HRS 12 YEARS -1+2 OR 1500 FLT HRS Mirage Aircraft Publications 2. The Mirage aircraft publications are design to provide all the necessary technical details, required for its operation and maintenance. These publications are separate for each individual model and type of aircraft (except mentioned). The arrangement of these manual is in “TEXT” and “PLATE”. The text contains the description and plate contains its corresponding illustration of diagram. For further understanding these publications are divided into following categories. (a) Flight Manual. This manual is purely meant for pilot. It contain complete flight parameters and its envelope. Normal and emergency procedure and performance charts. Also brief aircraft systems description is covered for the pilot’s understanding of system. (b) Technical Hand Book. The technical hand book gives precise information on the function and location of aircraft component. Moreover, it gives detail description of aircraft system and its associated equipment. (c) Maintenance Manual. These maintenance manual are also arranged in same manner i.e ‘Text’ and ‘Plate’. It provides all the information required to perform the technical operations in the aircraft. These are further classified into following:- 26 RESTRICTED  RESTRICTED (i) General Information Book. This book gives the description about the arrangement of the maintenance manual and the break down and constitution of other maintenance books. Moreover it gives the maintenance cycle and the list of all the maintenance procedures to be performed on aircraft. It also list the equipment to be removed for work shop maintenance and also provides the details of miscellaneous products. (ii) 1st Line Maintenance Book. It gives the information about routine servicing procedures and basic maintenance procedures. This book is further divided into three volumes (A) Vol 1 Routine Servicing. It gives the routine servicing procedure corresponding to group No 0 of the ‘GENERAL INDEX’. (B) Vol II 1st Line Maintenance. In this book maintenance operation corresponding to groups 1-2-3-4-5-8 are mentioned. (C) Vol III Routine and 1st Line Servicing (Navigation and Weapon System). This book contains the servicing procedures corresponding to sub group 04 and to groups 6-7-9. These groups and sub groups contains the information about Navigation and weapon system only (iii) 2nd Line Maintenance Manual. This book contains the work sheet and of the associated plates related to the minor maintenance procedures. (iv) Repair Manual. This book provides the information regarding logistic and technical information dealing with ageing or accidental damages. Moreover, it also provides the set of worksheet dealing with replacement of major items and various repair techniques. (v) Storage, Transportation, Conditioning and Packing. This book provides all necessary instruction for operations and servicing to be carried out on storage aircraft. Along with that it also gives the information about proper technique for packing and shipment of aircraft components. (vi) Life Book. This book contains the information about the life of aircraft components (vii) Individual Component Hand Book. Technical publication or illustrated part break down of an individual equipment, generally used in back up shops. 27 RESTRICTED  RESTRICTED (viii) Tester Book. A handbook of each tester, used in the maintenance operation of the aircraft. (d) Illustrated Parts Breakdown. This book provides the list of component and parts which make up the general composition of the aircraft. The figures illustrates the location of each part in the aircraft system. The IPB consists of following six chapters. (i) Chapter I. Introduction and concise parts list. It provides general information and the method for using the IPB. (ii) Chapter II. Detailed parts list, broken down into 9-sections. This chapter comprises the sections numbered from 0 to 8 (A) Sections 0. General alpha numerical index of manufacturer’s part numbers. It comprises all the parts listed in the description column of Sections 1 to 8 of Chapter II. The arrangement of Part Number is in the alpha numeric form. (B) Sections 1. Wing Structure. It gives all the components of the wing structure (C) Sections 2. Fuselage Structure. It gives all the components of the fuselage structure. (D) Sections 3. Fin and Rudder complete (Structure). It gives all the components of the fin and rudder complete structure. (E) Sections 4 Landing gears. It gives all the components of the landing gears. (F) Sections 5 Engine installation - Fuel system. It gives all the components of the engine and the fuel system. (G) Sections 6. Electrical System. It gives all the Electrical and Electronic system components (H) Sections 7. Accessory system installation and circuits. It gives all the components of hydraulic, pressurization and oxygen system. (J) Sections 8. Armament. It gives the components of the armament system. 28 RESTRICTED  RESTRICTED (iii) Chapter III. List of Applicable Publications. It is the list of Applicable Publications (L.O.A.P). (iv) Chapter IV. Ground equipment. This chapter contains lists of all the special tools and equipment used for aircraft servicing. (v) Chapter V. Repair size parts, special installation parts. It contains the list of fitted out assemblies and the repair size or semi finished parts identified in Chapter II by an asterisk entered to the left of the manufacturer’s part numbers. (vi) Chapter VI. Raw Materials. It contains the list of raw materials and servicing products required for repairs. It is in alphanumeric form. (e) Mirage Publications The breakdown of Mirage publication is given in a free format. 29 RESTRICTED  RESTRICTED Ground Support Equipment 3. Ground equipment is important for airworthiness of all aircraft. For effective maintenance it is important to keep the ground equipment in serviceable state. The following are the major ground equipment used for maintaining Mirage aircraft. 30 RESTRICTED  RESTRICTED (a) Tripod Jack. These jacks are used for jacking the aircraft for different purpose. (b) Telescopic Jack. These jack are smaller in size and are used for removal and installation of aircraft wheels. (c) Tow bar Long. It is used for towing the aircraft with tractor. (d) Tow bar Small. These tow bars are used for towing the aircraft manually. (e) Nitrogen Trolley. They are used for charging the nitrogen in the aircraft. (f) Oxygen Trolley. They are used for charging the oxygen in the aircraft. (g) Ladder Cockpit. This is used for step in and step out from cockpit. (h) Crash Trolley. This is used for recovering the aircraft in case of emergency from runway. (j) Hosting Crane. This is used for removal and installation of canopy of DP aircraft (Dual seater aircraft). (k) Engine Installation Dolly. This is used for removal and installation of engine from aircraft. (l) Oil Dispensers. These are used for re-oiling of engine and alternator. (m) Aircraft Starting Deflector. This is used for starting the aircraft, while aircraft standing in opposite wind direction. (n) Drip Trays. These are used to be kept under the aircraft for fuel, hydraulic and oil dripping from the aircraft. (p) A/B Chocks. These are used for Full-power Ground Run. (q) Aircraft Main Wheel Chocks. These are wooden chocks and used while aircraft are parked. (r) Defuelling Tube. This is used for defuelling the aircraft main fuel cells. (s) Stand Cylinder. This is used for placing the cylinders. (t) Drag Chute Stand. This is used for placing the Drag Chute. 31 RESTRICTED  RESTRICTED (u) Jig Canopy Stand. This is used for placing the Mirage-V PA and DP aircraft canopy. (v) Gun Bay Tank Stand. This is used for placing the gun bay tanks. (w) Canopy Lifting Sling. This is used for removal and installation of DP aircraft canopy. Monitoring Corrosion on Aircraft 4. Corrosion prevention and control is of major importance to the PAF, because corrosion has a great effect on the operational capability and structure of an aircraft and its equipment. Corrosion prevention /control is the responsibility of the custodian of the equipment. Therefore, always be on the look out for signs of corrosion and immediately inform your supervisors, if you notice corrosion on any part of the aircraft. (a) Particular Areas to be Inspected on Mirage. (i) Air intakes and start of air intake ducts. (ii) Auxiliary air intakes. (iii) Undercarriage wells. (iv) Quick visual inspection of Hydraulic couplings, small parts and hardware in steel. (b) Nose Undercarriage. (i) Leg assembly (paint flaking) (ii) Tow fitting; also check the hinges for free movement by actuating (iii) Support clamp vicinity. (iv) Lower section of strut (under plates and clamps) (v) Inner and outer faces of fork ends. (vi) Correct rotation of the locking roller. (vii) Shield doors and link rods. (c) Main Undercarriages. (i) Leg assembly for paint flaking. 32 RESTRICTED  RESTRICTED (ii) Support clamp and plate vicinity. (iii) Door control linkages. (iv) Wheels. (v) Correct rotation of locking rollers. (d) Blast Tube Vicinity. (e) Airbrakes. (f) Cockpit. (i) Lower attachment points of windshield. (ii) In the case of corrosion, remove the paint and perform a crack inspection; if a crack is detected, refer to the referenced worksheet. Aircraft Safety 5. (a) Safety Precautions. Proper safety precautions must be taken to protect the aircraft, accessories, equipment, and the maintenance personnel working on the aircraft, as follows:- 33 RESTRICTED  RESTRICTED (b) Aircraft Safe for Maintenance. (Ref JG-Mirage 2-01-001). The aircraft “safe for maintenance” function provides standardised instructions to ensure that the aircraft has been properly configured after return from flight or upon completion of a maintenance, inspection, or operational requirement. Prior to all maintenance, the aircraft is parked in the general maintenance area with chocks and landing gear safety pins installed and the cockpit canopy open. To make the aircraft safe for maintenance, the following tasks must be accomplished. When cockpit entry is not required, the aircraft is safe if all external locking devices are installed. When cockpit entry is required, it is necessary to ensure that the cockpit is safe for entry as well as installing all external locking devices. When power is to be applied, it is necessary to ensure that the aircraft is safe for power application as well as the cockpit being safe for entry and the external locking devices installed. All procedures to make the aircraft safe for maintenance are discussed in JG MIR 2-01-001. Mirage A/C is equipped with ejectable seat and canopy, jettisonable fuel tanks, powered flight controls, retractable /landing gears and air brakes etc. Inadvertent operation of any of these could lead to a serious inquires to personal and great damage to aircraft. It is therefore essential that all the personnel working on the aircraft understand its dangerous aspect and observe the pre-cautions as follows: (i) Check the aircraft form-781 series for current status of the aircraft. (ii) Make entry, A/C to be made safe for maintenance in Form 781A, which is to be cleared by all trades. (iii) Remove only those picketing covers of the aircraft where maintenance or inspection is required. (iv) Check that earthing is properly installed from ground to aircraft. 34 RESTRICTED  RESTRICTED (v) Check that the fire extinguisher is available in serviceable condition. (vi) Place the trestle near the wing. (vii) Install the ladder and open the canopy as per JG-MIR-2-01-001. (viii) Before entering the cockpit check that:- (A) All the fire pins of ejection seat are installed properly. (B) All the cockpit safety pins are installed Qty five. (C) Seat mat is positioned. (ix) After entering the cockpit check the cockpit layout as below:- (A) Right Console. (1) All the circuit breakers are “IN” except for EMG PUMP, SERVO, PITCH and A/H. (2) Lead light fully home. (3) Demist lever fully back. (4) Ram air lever forward. (5) IFF – OFF (6) Armament control panel – OFF (7) EMG COLD – OFF and wire locked. (8) Gyro centre – OFF (heading selector on “SET”) (9) INAS – OFF (10) Equipment air conditioning – “ON” (EMG COLD OFF) (11) TACAN – OFF (12) Parking brakes – OFF (13) Hydraulic pressure gauge switch on “SERVO” (14) Battery – OFF (15) Generator and Alternator –ON wire locked (16) Inverter – OFF (17) Emergency pump – OFF (18) Probe heater – OFF 35 RESTRICTED  RESTRICTED (B) Instrument Panel. (1) Load shed – UP (2) Dingy puncture in position (3) Cross feed – OFF (4) Check all gauges and lights for security (5) Stand by compass and clock serviceable (6) Store jettison button guarded (7) AC emergency disengage “NORMAL” (8) Canopy jettison lever “Board” wire locked (9) Brake chute lever forward (C) Left Hand Console. (1) Under carriage emergency handle fully home (2) AC gain switch “FWD” (3) Flight control panel II push buttons out (4) Undercarriage lever down (5) Mini stop – ON wire locked (6) Navigation and formation lights switches OFF (7) Landing light switch – OFF (8) Emergency nozzle switch – OFF (guarded properly) (9) Approach control lever forward and wire locked (10) Relight – OFF, wire locked (11) Throttle free in movement and then put it OFF (12) Air brake switch – IN (13) Gun sight caging – OFF (14) A/B cock – ON wire locked (15) Main LP cock – OFF (16) Ignition / ventilation switch to “IGN” 36 RESTRICTED  RESTRICTED (c) Aircraft Safe for Electrical Power. Before connecting electrical power on the aircraft the following precaution are to be strictly observed by all concerned: - (i) Check AFTO Form 781A to ensure that the A/C is fit for putting the power ‘ON’.Aircraft be made safe as per JG-MIR 2-01-001. (ii) A serviceable fire extinguisher should be available close to the aircraft. (iii) Check the cockpit of the aircraft as per JG-MIR 2-01-001. (iv) Auxiliary power units power plug and the aircraft power receptacle should be in serviceable condition. (v) Check the AP voltmeter for correct output voltage. (vi) Check the serviceability of APU lead plug to avoid any direct metal portion connect with aircraft skin. (vii) APU should be parked in such a way that maximum length of its lead is utilized for providing power to the aircraft. (viii) There should be no spillage of fuel or oil under the aircraft. (ix) No oxygen charging is to be carried out while electrical power is ‘ON’. (x) External power plug is to be removed after use of electrical power is over. 37 RESTRICTED  RESTRICTED (d) Hazardous Area. When the aircraft is powered or when the engine is running, certain areas become hazardous to the technicians working around it. Due care must be taken while working in the following areas. (i) Air Intake Area. During engine start engine air intake must be kept clear in front of the aircraft within 23 feet radius. (ii) Exhaust Area. During engine start the exhaust area must be kept clear at the rear within 81 feet with jet deflector and 195 feet with out jet deflector. (iii) Control Surfaces. When the hydraulic systems are pressurized, the control surfaces must be kept clear to avoid injury to the personnel. (iv) Speed Brakes. When the hydraulic systems are pressurized the Speed Brake area should be kept clear to avoid injury. (v) Antennas. Technicians should exercise vigilance and save themselves from injury from antennas and impact temp probe under the A/C. (e) Safeties during Ground Run. Following safeties must be strictly observed during Ground Run. (i) Aircraft is to be given ground run only by those personnel who are duly authorized and hold a valid AFTO Form-35. (ii) Aircraft is to be parked at the area specified for the particular ground run and heading into the wind (as far as possible) (iii) Aircraft forms should be reviewed before ground run to ensure that no discrepancy outstanding which could render the aircraft unfit for ground run. (iv) Operator should go around the aircraft and look for any obvious leaks or any other discrepancy. Ensure no fuel spillage on, under or around the aircraft. Any traces of fuel or oil must be first cleaned. (v) Fire extinguisher should be positioned and manned by fireguard. (iv) All picketing covers should be removed. (vii) Aircraft intakes and exhaust area should be absolutely clear. (viii) The chock should be positioned properly. 38 RESTRICTED  RESTRICTED (ix) Intake inspection for FOD, loose rivets, screws to be carried out. (x) Ensure, that all cockpit safety pins are in position and there are no loose items. (xi) Airmen of various trades required to check the aircraft during ground run, must be present near the aircraft. (xii) There should be no refueling operation carried out within 50 ft of the aircraft. (xiii) To eliminate the chances of FOD, area specified for ground run is to be thoroughly cleaned. Remove the un-necessary equipment from near the aircraft. (xiv) No loose clothing item e.g. sun caps, or handkerchief are worn/held by any person available near the aircraft being ground run. A/C at A/B Point (f) Precaution for Refueling / Defueling. Refueling and defueling of an aircraft is a hazardous operation and requires strict observance of laid down instructions. General precautions are listed in the following paras:- (i) Smoking, carrying matches or lighters and use of anything that might cause ignition/spark is prohibited within a distance of 50 feet. In case of 100 octane the distance will be 100 feet. Personnel employed on refueling / defueling operation should worn the shoes with rubber soles. Sign boards with the script. No smoking within 50/100 (as applicable) feet are displayed to caution all concerned. 39 RESTRICTED  RESTRICTED (ii) Refueling/defueling of aircraft is to be undertaken after allowing cooling time such that the aircraft skin surrounding the engine can be touched by bare hands with out feeling of burning. (iii) During refueling no other operation is permitted on the aircraft. All electrical switches be place in ‘OFF’ position. During power ‘ON’ refueling of Mirage aircraft, only cross feed cock switch and both main LP pumps switches will be put ‘ON’ in cockpit. (iv) All servicing equipment e.g Hobart Testers etc, which are not required near the aircraft are to be removed to a safe distance. (v) The aircraft refueling operation is to be performed by a team of minimum three technicians and bouser driver. (A) Bouser operator for controlling and manning the rear engine of the refueler. (B) Crew Chief for charging fuel in the A/C (C) Fire Guard formatting fire extinguisher. (D) Bouser driver (vi) A Serviceable Fire Extinguisher 25 Lbs Should Be Available Close To The Aircraft. (vii) Refueling / Defueling Operation Should Not Be Carried Out During Rain Or Heavy Dust Storm. (viii) The Technician Should Be Trained On Refueling/Defueling Operations And Should Be In Possession Of Valid AFTO F-35. (ix) Refueling / Defueling Should Not Be Done Inside Or Within 100 Feet Of A Hanger Or Any Building Except Aircraft Pen. (x) No Fuel Spillage Should Be Allowed With In 50 Feet Of Aircraft Being Refueled. (xi) No Naked Light Is Brought With In 50 Feet. (xii) No Taxing Ground Run Or Towing Is Done Within 50 Feet. Action In Case of Aircraft Fire 6. Responsibilities of Fire Crew during Ground Run:- 40 RESTRICTED  RESTRICTED (a) The crash tender is to be parked about 60 ft away, facing the aircraft clearing the wing tip. (b) The driver remains at his seat, with the crash tender engine running throughout the aircraft ground running operation. R/T set is continuously monitored. One crewmember remains stand by with the roof mounted ejection nozzle ready for operation. (c) All crew member must wear ear protection devices throughout the ground running. (d) The hose is to be unreeled and checking of correct selection of switches before start of run is mandatory, to reduce the reaction time in case of any emergency. (e) During night operation the search light and the parking light of the crash tender must remain ‘ON’ throughout the ground run. Access Doors and Panels 7. Doors and panels are provided on the aircraft to access various equipment during maintenance. The panels are flushed with the contour of the aircraft to ensure maximum aerodynamic shape of the aircraft. During maintenance these panels are frequently removed and installed. As technicians you have to take care that the panels maintain their shape and thus remain flushed with the aircraft body when installed. The panels are mostly secured with screws. It is to be noted that there are various sizes of screws available and installing the right length of screw is of the utmost importance. Cases have occurred where incorrect length of screw has damaged the aircraft body. Your instructor will show the various sizes of screws. He will also demonstrate to consult the publication in case you need to find the correct screw dimensions to be installed on the panel. Aircraft Work Areas 8. Mirage aircraft is divided into seven work areas:- Work Area 0 Aircraft general. Work Area 1 Nose section upto air intake including nose wheel well and nose landing gear. Work Area 2 Right wing including wheel well Work Area 3 Aircraft fuselage including engine Work Area 4 Left wing including wheel well Work Area 5 Tail section including tail cone Work Area 6 Cockpit and canopy. 41 RESTRICTED  RESTRICTED Aircraft Picketing 9. Picketing the aircraft means to cover and protect the sensitive areas from FOD, dust, rain and sunrays. When the aircraft is not in operation it should be picketed. The various covers and picketing equipment used on the Mirage aircraft are listed below. Your instructor will familiarize you with the various covers and their method of installation. (a) Pitot Probe Cover (b) Canopy Cover (c) Air intake cover (d) Angle of attack probe cover (e) Total pressure head cover (f) Turbo pump blanking cap (g) Total Temperature probe cover (h) Approach Speed static probe cover (j) Rain cover (k) Exhaust cover (l) Boundary layer bleeds cover Towing of Aircraft 10. Towing the aircraft is a major ground handling activity undertaken by the ground crew. Though it is done very frequently, yet all precautions must be strictly adhered to ensure safety of the aircraft. (a) Precautions before Towing. Before towing operation check the following:- (i) AFTO Form – 781 to determine the condition of the aircraft prior to movement. (ii) Tow bar for serviceability. (iii) Landing gear lever in ‘DOWN’ position. (iv) All cockpit safety pins installed. (v) Ground equipment and other obstructions removed (vi) Ground crew manning the brake in the cockpit must possess a valid AFTO Form 35. (vii) Ensure complete serviceability of park or emergency brakes before towing or pushing the aircraft. 42 RESTRICTED  RESTRICTED (b) Precautions during Towing. Following precautions are to be observed during towing operation. (i) Sudden start and stops are to be avoided. (ii) On the tarmac the towing out/in is to be carried out in the lanes specified for this purpose. (iii) Towing speed should not exceed 8 kilometer/hrs. (iv) During towing in closed area two wing walkers are to be detailed for wing tip clearance. (v) During towing in open area there should be only two technicians, one in the cockpit for brake manning, and the other on the tractor. In case of breakage of the shear pin, the technician on the tractor is to shout for indicating the pin breakage to the man in cockpit and direct the tractor driver to speed up the tractor. The tractor driver will then speed up the tractor and clear the area of the aircraft. The technician in the cockpit will apply the brakes and the technician on the tractor will install the chocks. (vi) For towing operation at night wing tip lights is to be put ‘ON’. (c) Precaution after Towing. After the towing operation, ensure the following:- (i) Towing arm is removed (ii) Chocks are placed on the main wheels. (iii) Install the earthling cable. (iv) Fuel drip tray is placed under the aircraft (v) Aircraft is picketed. Your Responsibility as a Technician 11. Now that you are equipped with the basic knowledge of Mirage Aircraft. It is for you to develop the skills to become a proficient technician and perform the task of maintaining the aircraft with utmost devotion. Remember that a careless mistake, an undesirable shortcut and a shoddy work may result in a loss of life and equipment. 43 RESTRICTED  RESTRICTED CHAPTER 1 ENGINE GENERAL DESCRIPTION Introduction 1. The ATAR 09C5, 09C6 and 09C8 is a turbo jet engine with a variable area exhaust nozzle to facilitate afterburner operation. ATAR is a name given to the engine, 09C indicates its model and 5, 6 & 8 is a version. This engine is manufactured by SNECMA Company of France. It is used to power MIR V & MIR III Aircraft manufactured by AMD (Avions Marcel Dassault) of France. In PAF this engine is operated on fuel grade JP-8 but this engine can be operated on other fuel grade such as JP-1 by adjusting the density corrector which is fitted in its fuel circuit. A self-contained kerosene starter is fitted in this engine which is a complete turbojet engine and is used for starting the main engine on ground only. Atar 09C Engine 44 RESTRICTED  RESTRICTED Leading Particulars 2. (a) 9 Stage axial flow compressor (b) Annular combustion chamber (c) Two stage turbine (d) Jet pipe with A/B chamber and a variable area exhaust nozzle, which is adjustable by flaps. (e) Fuel flow is controlled hydraulically by a single lever (throttle). (f) Approach control unit. (g) Self contained kerosene starter. (h) Fuel dipper system. (j) Weight:- (i) Total weight - 3106 lbs. + 2% (ii) Weight of the jet pipe - 882 lbs. Constructional Details 3. (a) Direction of rotation - Clockwise (viewing from rear) (b) Compressor:- (i) Type - Axial flow with bearing No1and 2 (ii) Rotor - Drum with steel discs. (iii) No. of stages - Nine (iv) Compression Ratio - 5.5 : 1 (c) Combustion Chamber:- (i) Type - Annular (ii) No. of burners - 20 (iii) No. of two flow injectors - 20 (iv) No. of ante chambers - 2 45 RESTRICTED  RESTRICTED (v) No. of igniter plugs - 2 (d) 1st Stage Turbine and Nozzle Guide Vane Assembly:- (i) No. of vanes - 42 (ii) Type of vanes - Hollow air cooled (e) 2nd Stage, Turbine and Nozzle Guide Vane Assembly:- (i) No. of vanes - 56 (ii) Type of vanes - Solid un-cooled (f) Turbine (i) Type - axial flow reaction type with bearing No.3. (ii) No of stages - 2 (iii) No of blades - 1st Stage 73 2nd Stage 50 (iv) Type of blades - Solid un-cooled with fir-tree roots. (g) Jet Pipe:- (i) Junction section (A) A/B fuel supply - 2 Burner rings & 3 upstream manifolds. (ii) Nozzle Support (iii) Variable area nozzle - 18 hot flaps controlled by 9 actuators. 18 Cold flaps slaved to hot flaps with link rods 46 RESTRICTED  RESTRICTED Jet Pipe 4. Operation Limitations Table LIMITS OF TEST BENCH LIMITS IN FLIGHT FUEL THRUS SPEED TEMP CONSUM TEMP RPM ‘N’ T ‘F’ RPM ‘N’ SETTING T-4 0C ‘C’ LB/HR T-4 0C (lbs) Max with 8650+ 50 A/B & over 14000 715 - 103% 760 103 +.6% speed Max with A/B & 8400+ 50 13232 700+5 26900 100+.6% 680-740 without over 100+.6% -10 speed Max without 8400+50 700+5 A/B & over 9480 9570 100+.6% 680-740 100+.6% -10 speed 2900+100 Idle 265 500 Positive - - 34.7+1.2% Cockpit Layout of Engine Controls 5. The layout of switches, gauges and indicators used for engine operation. 47 RESTRICTED  RESTRICTED Cockpit Layout Throttle RPM Gauge 48 RESTRICTED  RESTRICTED Starting Button 18 Warning lights Symbols and their Description 6. Symbols Description TO Temperature of air just in front of engine intake. (Atmospheric temperature) T1 Temperature of air in the engine intake. T2 Temperature of air at the end of compressor. T3 Temperature of gases before turbine. T4 Temperature of gases after turbine. T5 Temperature of gases - outgoing of the exhaust nozzle. P0 Atmospheric pressure. P1 Pressure in the engine intake. P2 Pressure at the end of compressor. P3 Pressure before turbine. P4 Pressure after turbine. P5 Pressure at the end of exhaust nozzle. A5 Area of the exhaust nozzle. Increases Decreases N R.P.M. Z Altitude F Thrust C Fuel Consumption P Differential pressure B Reduction factor of P2 air 49 RESTRICTED  RESTRICTED BP2 Reduced P2 from the pressure reducer B'P2 Reduced P2 from flyweight stop corrector to double stop unit. B"P2 Reduced P2 from approach control to temperature control unit. < Less or equal to > More or equal to F/ P Fuel air mixture ratio  Internal gas pressure. Ph Low oil pressure PHP High oil pressure. Pca Fuel inlet pressure (low) Prp Sec Fuel pump delivery pressure. Pid Starting fuel injection pressure. Pip Fuel injection pressure (Main flow) Pib Fuel injection pressure (Pilot flow) Pot Oil pressure nozzle opening. Pft Oil pressure nozzle closing. Pi RA Fuel manifold pressure (upstream manifold). Pi AB Fuel manifold pressure (burner rings) Prp Pc Delivery pressure of A/B turbo pump. 50 RESTRICTED  RESTRICTED CHAPTER 2 ENGINE GENERAL CONSTRUCTION Introduction 1. ATAR 09C5 is a turbojet engine its source of energy being fuel. Chemical energy is converted into thermal energy which is used for producing thrust. Sections 2. Structurally, the engine can be divided into following six sections which will be described in the subsequent paragraphs. (a) Intake section. (b) Compressor section. (c) Central casing. (d) Combustion chamber. (e) Turbine section. (g) Jet Pipe. Intake Section Intake Section 3. The intake section is located at the front of the engine. It comprises of the following parts. 51 RESTRICTED  RESTRICTED (a) Self contained kerosene starter. (b) The casing and its six spokes (c) No 1 bearing of the compressor. (d) The compressor intake guide vane assembly. (e) The reduction gear box. (a) Self Contained Kerosene Starter. The self kerosene starter is a small but complete turbojet engine which is used as a starter for starting the main engine on the ground only. The construction, description and its operation is given in the chapter of starting system. Self Contained Kerosene Starter (b) The Intake Casing and its Six Spokes. There are six spokes in the air intake section. The purpose and function of each spoke is given below. Intake Casing 52 RESTRICTED  RESTRICTED (i) Spoke No. 1. It houses oil lines for the lubrication of reduction gear box and No.1 bearing. The casing ventilation is also effected through this spoke. It also houses the thermocouple connections to check the temperature of No. 1 bearing. (ii) Spoke No. 2. It houses fuel line for the gas generator, air line for conveying P2 air pressure signal from the Gas Generator combustion chamber to the starting fuel control unit and the oil line for the emergency lubrication of No. 1 bearing. Also contains the Piston balance chamber pressure connection. (iii) Spoke No. 3. It houses a drive shaft which transmits the drive from reduction gear box to the accessory angle drive. (iv) Spoke No. 4. It houses drain lines for oil from No. 1 bearing and from reduction gear box and houses the Gas generator chamber fuel drain. (v) Spoke No. 5. It houses a drive shaft which transmits the drive from the reduction gear box to the aircraft power take off. (vi) Spoke No. 6. It houses six electrical leads for the engine starting system. (A) Two leads for spark plug (B) Two leads for electrical motor. (C) Two leads for thermostat switch. Intake Casing 53 RESTRICTED  RESTRICTED. No 1 Bearing (c) No 1 Bearing of Compressor. This is a duplex race ball bearing; it retains the compressor front shaft and absorbs the residual axial reaction from the shaft. The front labyrinth cover has a ring shaped container to collect oil which has lubricated the ball race. A duct allows the oil to flow to spoke No.4 (d) The Compressor Inlet Guide Vane Assembly. It consists of 31 hollow vanes which are made of steel. These hollow vanes direct intake air to the compressor first stage blades at a correct angle. Each vane is secured separately to the intake casing and the labyrinth ring. Anti-icing air, which is taken from ninth stage of compressor, enters from the front bottom of the vanes, flows to the top and escapes from the aperture at the trailing edge bottom. Thus it avoids ice formation on the hollow guide vanes at high altitude. Compressor Inlet Guide Vanes Reduction Gear Box 54 RESTRICTED  RESTRICTED (e) Reduction Gear Box. The reduction gear box is located in the intake casing, between the starter and the compressor. It contains three bevel gears to transmit the drive of the engine to the accessory angle drive and the aircraft (PTO) shaft. Compressor Section 4. The compressor section consists of the rotor assembly and stator assembly which are described below. (a) Rotor Assembly. There are nine stages of blades in the rotor assembly. No. 1 stage blades are of snubber type construction for greater rigidity to avoid fluttering. Blades of stage No 1,2,7,8 and 9 are made of steel and those of stages 3, 4, 5 and 6 are made of light alloy. The blades are mounted on steel discs. These discs are centered on each other by very precise machining and fixed by screws. The first stage disc has a stub shaft which is an integral part of the first stage rotor disc. The No. 1 bearing is mounted on this shaft. A double labyrinth seal located here prevent the hot compressor discharge pressure (C.D.P) air from affecting the No. 1 bearing. A second stub shaft is mounted to the rear of the No. 9 stage disc by means of bolts. No 2 bearing is mounted on this shaft. The turbine shaft is also coupled to it by a coupling sleeve and a screw -mechanism. Rotor Assembly (b) Stator Assembly: The stator casing is cylindrical in shape and is cut in two halves with the centre line horizontal. The top half is removed for internal inspection of compressor. It is made of magnesium alloy casing. The front of the stator assembly is secured to the intake casing and the rear to the central casing. First two stages are made of stainless steel and rest six stages are made of light alloy. Accessory support and most of the engine components are fitted on the stator casing. On each side of the upper half 55 RESTRICTED  RESTRICTED casing there are two air tapings for cooling and atomizing of the lubricating oil for the No.2 and No.3 bearings. Stator Assembly Central Casing 5. The central casing contains the following sub-assemblies:- (a) The compressor out let guide vane assembly (b) The burner ring and its twenty burners. (c) Two ignition ante-chambers. (d) The rear bearing of the compressor (No.2 bearing). (e) Rear double labyrinth seal of compressor. (f) Air collector (g) 10 Hollow spokes 56 RESTRICTED  RESTRICTED Central Casing (Front View) Central Casing (Rear View) Combustion Chamber Burner Ring (a) Compressor outlet Guide Vane Assembly. The compressor outlet guide vane assembly is located at the rear of the compressor casing. It comprises of two rows of 90 profiled vanes which are made of steel. The vanes are secured to an inner ring and outer ring by studs fitted into the rings. (b) Burner Ring and 20 Burners. The burner ring is located at the central casing outlet. It is made of light alloy and comprises twenty cavities each containing a burner. The ring also acts as a support for the outer and inner combustion chamber. (i) Burners. Twenty burners which are made of stamped steel sheet are mounted on the burner ring. A locking plate is bolted to the burner ring which holds the burner in position. Each burner contains a two flow injector. The burners are designed in such a way as to divide 57 RESTRICTED  RESTRICTED the primary air into several thin jets. Thus the primary air and the fuel atomized by two flow injectors mix correctly for optimum combustion. (c) Ignition Ante-Chambers. The central casing has two ignition ante- chambers symmetrically located in relation to the vertical axis of the engine, in the lower right and left hand side of the burner ring. Each ignition ante- chamber is a housing in which a glow plug and a starting injector is fitted. Apertures provided permit the P2 air to enter the combustion chamber. The mixture of gases in the housing ignites upon contract with the electrodes of the ignitor plug. The combusted gases pass to the adjoining burners through two lateral ducts. (d) Rear bearing of the compressor. This bearing is also called No. 2 bearing of the engine. It is a roller bearing and is mounted in the central casing. (e) Rear double labyrinth of the compressor. The labyrinth is secured to the air collector and consists of an inner labyrinth ring and an outer labyrinth ring. Both the rings are fitted together by screws to form the double labyrinth. (f) Air collector. A circular air collector is located in the central casing. Some of the P2 air after passing through the compressor discharge guide vanes, is collected in the air collector from where four air tapings are taken for:- (i) Operation of the afterburner turbo-pump (ii) Tank pressurization (iii) Cabin pressurization. (iv) Air conditioning of the equipment. (g) Hollow Spokes. The central casing has ten hollow spokes through which air, lubricating oil and electrical connections etc. are passed. The purpose of each spoke is given below:- (i) Spoke No. 1. It supports the upper main suspension. (ii) Spoke No. 2. It permits the passage of P2 air to the afterburner turbo pump. (iii) Spoke No. 3. It carries the air and oil tubes for cooling and lubrication of bearing No.3. (iv) Spoke No. 4. It permits the passage of the air for tank pressurization. 58 RESTRICTED  RESTRICTED (v) Spoke No. 5. Houses two air pipes which are blanked and are used only on test bench in factory for the measurement of (лR & лRT pressure. It also permits the gravity flow of oil from bearing No 2 & 3. (vi) Spoke No. 6. It carries the oil scavenge tubes and permits the gravity flow of the oil to the oil return collector. (vii) Spoke No. 7. It carries the connections from the thermocouples of the bearings No 2 & 3 and pipes to the scavenged oil to the oil return housing. (viii) Spoke No 8. It carries pipes for the air conditioning of the equipment. (ix) Spoke No 9. It contains the air and oil tube for the cooling and lubrication of bearing No 2. (x) Spoke No 10. It contains the pipes for cabin pressurization and air conditioning system. 10 Hollow Spokes 59 RESTRICTED  RESTRICTED Combustion Chamber 6. (a) Location. The combustion chamber is located between the central casing and turbine assembly. (b) Functions:- (i) Contains combustion zone. (ii) Introduces secondary air in the combustion gases to reduce the temperature before reaching the turbine. (c) Construction. The chamber is of annular type and comprises the following parts:- (i) A cylindrical casing which has flanges on either side. These flanges are used to secure the combustion chamber to the central casing in front and to the junction section in the rear. (ii) An outer combustion chamber member. (iii) An inner combustion chamber member. Combustion Chamber (iv) All the above three parts are manufactured from stainless steel. The inner chamber is fitted inside the outer chamber thus forming an annular chamber where the main combustion takes place. Approximately 25% of P2 air going into the combustion chamber is utilized for mixing with the atomized fuel. Rest of the P2 air is used for completing the combustion and lowering down the temperature of combustion gases through holes provided in the outer and inner combustion chamber members. A combustion chamber drain is fitted to the lower part of the casing. This drain enables the un-burnt fuel to drain out when engine is shut down. 60 RESTRICTED  RESTRICTED Turbine Section 7. Turbine section includes the following main components:- (a) Turbine bearing support. (b) Two-stage turbine. (c) Coupling sleeve (d) First and second stage nozzle guide vane assemblies. Two-Stage Turbine Assembly Turbine Bearing Support (a) Turbine Bearing Support. The turbine bearing support is located at the rear of the central casing and comprises of the following: (i) The turbine support casing. (ii) The bearing support in which are fitted the rollers which comprise the bearing No 3. (iii) The turbine shaft protecting tube. (iv) The lubrication and cooling of bearing No 3. 61 RESTRICTED  RESTRICTED Turbine Bearing Support Casing (b) Two-Stage Turbine Assembly: The turbine assembly consists of two stages of rotor blades. All the turbine components are made of high tensile strength stainless steel (The blades in particular are made of refractory steel of high creep resistance). The two stages of the turbine rotor are described below: (i) First Stage Turbine Wheel. It is integral with the tubular turbine shaft. Seventy three blades are fitted to the wheel by fir tree roots, and each blade is retained in its position by a locking tab. Holes are provided to allow the cooling air to enter the space between the two turbine wheels. (ii) Second Stage Turbine Wheel. Comprises a disc to which 50 blades are fitted with fir tree roots. The roots are secured in their housings by locking tabs. Balancing plates are also fitted to the rear face of the wheel. It is coupled to the first disc by engaging teeth and banjo nut /bolt arrangement. (c) Coupling Sleeve. The compressor rotor is connected to the turbine shaft by a special sleeve called coupling sleeve. It prevents the assembly from coming apart or from being unscrewed by accident. It is also designed to eliminate some slight defect in the alignment of the compressor shaft and the turbine shaft. 62 RESTRICTED  RESTRICTED Turbine Coupling Sleeve (d) 1st and 2nd stage Nozzle Guide Vane Assemblies. On the front of each turbine wheel a circular row of stator vanes is fitted which guides the air flow on to the turbine wheels. These are called nozzle guide vane assemblies. Nozzle Guide Vane Assemblies (i) First Stage Guide Vane Assembly. It is located at upstream from the first stage turbine wheel and incorporates 42 hollow, air cooled vanes. The guide vane assembly guides the gases from the combustion chamber to the first stage of the turbine in a pre- determined direction. (ii) Second Stage Guide Vane Assembly. It is located between two turbine wheels and incorporates 56 solid vanes. It directs the flow of gases from the first stage turbine wheel to the second stage turbine wheel. 63 RESTRICTED  RESTRICTED Jet Pipe 8. The jet pipe of the ATAR 09C engine consists of three main parts which are:- (a) The junction section (b) The nozzle support, immediately following the junction section. (c) The nozzle which is fitted to the nozzle support. The cross sectional area of the nozzle is regulated by eighteen flaps. Jet Pipe (a) Junction Section. The junction section incorporates five spokes and is fitted immediately behind the combustion chamber. It guides the hot gases between the turbine exhaust and the after burner chamber. It also incorporates two burner rings and three upstream manifolds through which the afterburner fuel is injected. The junction section comprises of an outer shroud which is made of heat resistant steel sheet. Inside it a truncated and blanked off cone is fitted. The outer shroud and the cone function as a diffuser in which the gas velocity decreases gradually before reaching the upstream manifolds and the burner rings. The following parts are also located in the junction section:- (i) Four Probes T4. (ii) Three drain connections:- (A) Central connection for oil coming from No 2 and 3 bearings. (B) Left hand connection for A/B pressurization and dump valve. (C) Right hand connection for fuel drainage at the start up.