aircraft general engineering and maintenance practices_ _ pritamashutosh

13/02/2016 AIRCRAFT GENERAL ENGINEERING AND MAINTENANCE PRACTICES: | pritamashutosh

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AIRCRAFT GENERAL ENGINEERINGAND MAINTENANCE PRACTICES:Posted on April 14, 2014

Mooring:

The following is a list of equipment need to park and/or moor (tie down) the airplane. • 4 wheel chocks • 3 screwin mooring rings (left and right wing, and tail) • 3 ropes (nylon or other nonshrinking/nonstretching synthetic material)

If wheel brakes are hot from prolonged taxi, allow brakes to cool before setting parking brake.

Controls may be secured with ailerons neutral and horizontal stabilizers leading edge down by pulling the control stick aft as far as possible and fastening seat belt snugly around it.

SHORTTERM PARKING Perform this procedure for shortterm parking of the airplane. 1. Taxi or tow airplane to desired parking position. 2. Align nose of airplane into the wind. 3. Ensure nose wheel is centered. 4. In windy or gusty weather, moor (tie down) the airplane, see Section 1020 Mooring (Tying Down) on page 11 of this chapter. 5. Set the parking brake.

If wheel brakes are hot from prolonged taxi, allow brakes to cool before setting parking brake. 6. Place chocks in front of and behind main wheels. 7. Release the parking brake. 8. Secure flight controls in neutral position; retract flaps. Follow

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Controls may be secured with ailerons neutral and horizontal stabilizers leading edge down by pulling the control stick aft as far as possible and fastening seat belt snugly around it. 9. Close and lock the doors.

LONGTERM PARKING Perform this procedure for longterm parking of the airplane. 1. Perform the steps for shortterm: parking. 2. Moor (tie down) the airplane, see Section 1020 Mooring (Tying Down) on page 11 of this chapter.. 3. Install external rudder lock if available.

ALL GUST LOCKS MUST BE REMOVED FROM THE AIRCRAFT PRIOR TO TAXIAND FLIGHT. CARE SHOULD BE TAKEN NOT TO DEFORM OR DAMAGE THE STRUCTURE DURINGINSTALLATION AND REMOVAL OF THESE LOCKS. ALL DEFOMRATION, DAMAGE ANDINTERFERENCE MUST BE REVIEWED BY A QUALIFIED MECHANIC OR TECHNICIAN PRIOR TO FLIGHT. 4. Install pitot/static, canopy, and propeller covers as applicable. 5. Refer to engine, electrical, and fuel system chapters of this manual for information onrequired servicing for longterm storage. The airplane has three mooring points: one under each wing, and one under the tail.Mooring rings are provided to secure tie down ropes into the mooring points. Park theairplane, see the procedures for short and long term parking of the airplane. Attach tiedown ropes to ground tiedowns and aircraft mooring rings. Leave sufficient playor looseness in the ropes to prevent inadvertent loading of the structure. Also, if using arope, tie a bowline knot to allow tension freedom.

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JACKING AIRCRAFT

The aviation technician must be familiar with the jacking of aircraft in order to performmaintenance and inspection. Since jacking procedures and safety precautions vary fordifferent types of aircraft, only general jacking procedures and precautions are discussed.Consult the applicable aircraft manufacturer’s maintenance instructions for specific jackingprocedures.



Extensive aircraft damage and serious personal injury have resulted from careless orimproper jacking procedures. As an added safety measure, jacks should be inspectedbefore use to determine the specific lifting capacity, proper functioning of safety locks,condition of pins, and general serviceability. Before raising an aircraft on jacks, all workstands and other equipment should be removed from under and near the aircraft. No oneshould remain in the aircraft while it is being raised or lowered, unless maintenancemanual procedures require such practice for observing levelling instruments in the aircraft.

The aircraft to be jacked must be located in a level position, well protected from the wind.A hangar should be used if possible. The manufacturer’s maintenance instructions for theaircraft being jacked should be consulted for the location of the jacking points. Thesejacking points are usually located in relation to the aircraft center of gravity so the aircraftwill be well balanced on the jacks. However, there are some exceptions to this. On someaircraft it may be necessary to add weight to the nose or tail of the aircraft to achieve asafe balance. Sandbags are usually used for this purpose.

Tripod jacks similar to the one shown in figure 1138 are used when the complete aircraftis to be jacked.



A small single base jack similar to the one shown in figure 1139 is used when only onewheel is to be raised. The jacks used for jacking aircraft must be maintained in goodcondition; a leaking or damaged jack must never be used. Also, each jack has amaximum capacity, which must never be exceeded.

Jacking Complete Aircraft

Prior to jacking the aircraft, an overall survey of the complete situation should be made todetermine if any hazards to the aircraft or personnel exist. Tripod jacks of the appropriatesize for the aircraft being jacked should be placed under the aircraft jacking points andperfectly centered to prevent them from cocking when the aircraft is raised. The legs ofthe jacks should be checked to see that they will not interfere with the operations to beperformed after the aircraft is jacked, such as retracting the landing gear.

At least three places or points are provided on aircraft for jacking purposes; a fourth placeon some aircraft is used to stabilize the aircraft while it is being jacked at the other threepoints. The two main places are on the wings, with a smaller one on the fuselage neareither the tail or the nose, depending on the landing gear design.

Most aircraft have jack pads located at the jack points. Others have removable jack padsthat are inserted into receptacles bolted in place prior to jacking. The correct jack padshould be used in all cases. The function of the jack pad is to ensure that the aircraft loadis properly distributed at the jack point and to provide a convex bearing surface to matewith the concave jack stem. Figure 1140 illustrates two types of jack pads.

Prior to jacking, determine if the aircraft configuration will permit jacking. There may be



equipment or fuel which has to be removed if serious structural damage is to be avoidedduring jacking. If any other work is in progress on the aircraft, ascertain if any criticalpanels have been removed. On some aircraft the stress panels or plates must be in placewhen the aircraft is jacked to avoid structural damage.

Extend the jacks until they contact the jack pads. A final check for alignment of the jacksshould be made before the aircraft is raised, since most accidents during jacking are theresult of misaligned jacks.

When the aircraft is ready to be raised, a man should be stationed at each jack. The jacksshould be operated simultaneously to keep the aircraft as level as possible and to avoidoverloading any of the jacks. This can be accomplished by having the crew leader standin front of the aircraft and give instructions to the men operating the jacks. Figure 1141shows an aircraft being jacked.

Caution should be observed, since on many jacks the piston can be raised beyond thesafety point; therefore, never raise an aircraft any higher than is necessary to accomplishthe job.

The area around the aircraft should be secured while the aircraft is on jacks. Climbing onthe aircraft should be held to an absolute minimum, and no violent movements should bemade by persons who are required to go aboard. Any cradles or necessary supportsshould be placed under the fuselage or wings of the aircraft at the earliest possible time,particularly if the aircraft is to remain jacked for any length of time.



On collet equippedjacks, the collet should be kept within two threads of the lift tube cylinder during raising,and screwed down firmly to the cylinder after jacking is completed to prevent settling.

Before releasing jack pressure and lowering the aircraft, make certain that all cribbing,work stands, equipment, and persons are clear of the aircraft, that the landing gear isdown and locked, and that all ground locking devices are properly installed.

Jacking One Wheel of an Aircraft

When only one wheel has to be raised to change a tire or to grease wheel bearings, a lowsingle base jack is used. Before the wheel is raised, the remaining wheels must bechocked fore and aft to prevent movement of the aircraft. If the aircraft is equipped with atail wheel, it must be locked. The wheel should be raised only high enough to clear theconcrete surface. Figure 1142 shows a wheel being raised using a single base jack.



Aircraft TowingOn aircraft with a nosewheel landing gear, a steering arm should be fitted to the nosewheel to guide the aircraft Light aircraft can be moved and guided, by hand or by a tug.

Special attention should be paid to the following:

Force should not be applied to the thin trailing or rear edges of wings or control surfacessuch as ailerons or elevators.Generally speaking it is better to push an aircraft backwards rather than forwards,

because the leading edges of the wings and tailplane are stronger than the trailing edges.The struts, which support the undercarriage on some aircraft, are suitable for pushing

the aircraft as these are the strength parts of the aircraft.

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The flat of the hands should be used when pushing, so as to spread the load over thelargest area.When pushing on struts, the force should be applied as near to the end fittings as

possible.A propeller must never be used to push or pull the aircraft, as the engine should always

be regarded as ‘live’ and a propeller may kick if it is turned.On aircraft with a steering nose wheel connected to the rudder pedals, care must be takennot to exceed the turning limits. Normally the maximum limits are marked on nose wheeldoors as “NO TOW”

On this type of aircraft it is also important that the rudder controls are not locked duringthe towing operations. This is because the rudder controls and the nosewheel steeringmechanism are interconnected and the excessive movements could damage themechanical linkages.

When towing aircraft by tow bar and tug special care should be given to below facts,

The correct towbar should be connected between the towing attachment at the base ofthe nose undercarriage leg and the tug.

A person familiar with the aircraft brake system should be seated in the cockpit/cabin tooperate the brakes in an emergency. The brakes should not normally be applied unlessthe aircraft is stationary.

Once the towbar is connected, the brakes, and if fitted, the rudder lock, may be releasedand the aircraft towed at a safe speed. A safe speed is considered to be walking speed.

A close watch should be kept on the wing tips and tail, particularly in confined spaces, toensure that they do not come into contact with other stationary or moving object.

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In circumstances where the ground over which the aircraft has to be towed is either boggyor very uneven, the strain imposed on the nose undercarriage may be excessive and itmay be necessary to tow the aircraft by means of bridles attached to each mainundercarriage. If towing attachments are not provided on the main undercarriage legs,ropes should be passed carefully around the legs as near to the top as possible andavoiding fouling on adjacent pipes or structure. A separate tug should be connected toeach main undercarriage assembly. Steering should be carried out by means of a steeringarm attached to the nose wheel rather than by differential movement of the tugs.

The most common means of towing a large aircraft nowadays is by means of a tow barless aircraft handling tractor.These tractors tend to be front wheel driven and thereforewhen towing an aircraft, are acting to ‘pull’ the tractor/aircraft combination.The towbarlesstractor consists of a low level tractor with a rear mounted cradle, comprising of a ‘scoopand gate’ assembly.

Owing to the tractor’s low height it can easily movein under the aircraft’s fuselage tocoupleup with the aircraft’s nose wheel. During operation the nose wheel is raised byabout 20cms by the tractor and after the towing is completed the nose wheel is loweredand the nose wheel is released from the cradle.

Engine Starting Procedures:

Piston Engine:

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The following procedures are typical of those used to start reciprocating engines. Thereare, however, wide variations in the procedures for the many reciprocating engines. Noattempt should be made to use the methods presented here for actually starting an engine.Instead, always refer to the procedures contained in the applicable manufacturer’sinstructions.

Reciprocating engines are capable of starting in fairly low temperatures without the use ofengine heating or oil dilution, depending on the grade of oil used.

The various covers (wing, tail, cockpit, wheel, etc.) protecting the aircraft must beremoved before attempting to turn the engine. External sources of electrical power shouldbe used when starting engines equipped with electric starters. This eliminates anexcessive burden on the aircraft battery. All unnecessary electrical equipment should beleft off until the generators are furnishing electrical power to the aircraft power bus.

Before starting a radial engine that has been shut down for more than 30 minutes, checkthe ignition switch for off; turn the propeller three or four complete revolutions with thestarter, or it may be pulled through by hand to detect a hydraulic lock if one is present.

Any liquid present in a cylinder is indicated by the abnormal effort required to rotate thepropeller, or by the propeller stopping abruptly during rotation. Never use force to turn thepropeller when a hydraulic lock is detected.

Sufficient force can be exerted on the crankshaft to bend or break a connecting rod if alock is present.

To eliminate a lock, remove either the front or rear spark plug from the lower cylinders andpull the propeller through. Never attempt to clear the hydraulic lock by pulling the propellerthrough in the opposite direction to normal rotation. This tends to inject the liquid from thecylinder into the intake pipe. The liquid will be drawn back into the cylinder with thepossibility of complete or partial lock occurring on the subsequent start.

To start the engine, proceed as follows:

1. Turn the auxiliary fuel pump on, if aircraft is so equipped.

2. Place the mixture control to the position recommended for the engine and carburettorcombination being started. As a general rule, the mixture control should be in the “idlecutoff” position for pressure type carburettors and in the “full rich” position for float typecarburetors.

Many light aircraft are equipped with a mixture control pull rod which has no detentedintermediate positions. When such controls are pushed in flush with the instrument panel,the mixture is set in the “full rich” position. Conversely, when the control rod is pulled allthe way out, the carburetor is in the “idle cutoff” or “full lean” position. Unmarkedintermediate positions between these two extremes can be selected by the operator to



achieve any desired mixture setting.

3. Open the throttle to a position that will provide 1,000 to 1,200 rpm (approximately 1/8 to1/2 inch from the “closed” position).

4. Leave the preheat or alternate air (carburetor air) control in the “cold” position to preventdamage and fire in case of backfire. These auxiliary heating devices should be used afterthe engine warms up. They improve fuel vaporization, prevent fouling of the spark plugs,ice formation, and eliminate icing in the induction system.

5. Energize the starter after the propeller has made at least two complete revolutions, andturn the ignition switch on. On engines equipped with an induction vibrator, turn switch tothe “both” position. When starting an engine that uses an impulse coupling magneto, turnthe ignition switch to the “left” position. Place the ignition switch to “start” when themagneto incorporates a retard breaker assembly. Do not crank the engine continuouslywith the starter for more than 1 minute. Allow a 3 to 5 minute period for cooling the starterbetween successive attempts. Otherwise the starter may be burned out due tooverheating.

6. Move the primer switch to “on” intermittently, or prime with one to three strokes ofpriming pump, depending on how the aircraft is equipped. When the engine begins to fire,hold the primer on while gradually opening throttle to obtain smooth operation.

After the engine is operating smoothly on the primer, move the mixture control to the “fullrich” position. Release the primer as soon as a drop in rpm indicates the engine isreceiving additional fuel from the carburetor.

Hand Cranking

If the aircraft has no self starter, the engine must be started by swinging the propeller. Theperson who is turning the propeller calls, “fuel on, switch off, throttle closed, brakes on.”The person operating the engine will check these items and repeat the phrase. The switchand throttle must not be touched again until the person swinging the prop calls “contact.”The operator will repeat ” contact” and then turn on the switch. Never turn on the switchand then call “contact.”

When swinging the prop, a few simple precautions will help to avoid accidents. Whentouching a propeller, always assume that the ignition is on. The switches which controlthe magnetos operate on the principle of short circuiting the current to turn the ignition off.If the switch is faulty, it can be in the “off” position and still permit current to flow in themagneto primary circuit.

Be sure the ground is firm. Slippery grass, mud, grease, or loose gravel can lead to a fallinto or under the propeller. Never allow any portion of your body to get in the way of thepropeller. This applies even though the engine is not being cranked. Stand close enough tothe propeller to be able to step away as it is pulled down. Stepping away after cranking is



a safeguard in case the brakes fail.

Do not stand in a position that requires leaning toward the propeller to reach it. Thisthrows the body off balance and could cause you to fall into the blades when the enginestarts.

In swinging the prop, always move the blade downward by pushing with the palms of thehand. Do not grip the blade with the fingers curled over the edge, since “kickback” maybreak them or draw your body in the blade path.

Excessive throttle opening and intermittent priming after the engine has fired are theprincipal causes of backfiring during starting. Gradual opening of the throttle while primingcontinuously will reduce the initial “over rich” mixture to a smooth running, best powermixture as the engine picks up speed. An engine operating on an “over rich” mixture issluggish but will not backfire.

When starting an engine using a priming pump, move the mixture control into “full rich”position, if not previously placed there, when the engine begins to fire. If the engine fails tostart immediately, return the mixture control to “idle cutoff” position. Failure to do so willcreate an excessive amount of fuel in the carburetor air scoop, constituting a fire hazard.

Avoid priming the engine before it is turned over by the starter. This can result in fires,scored or scuffed cylinders and pistons, and, in some cases, engine failures due tohydraulic lock. If the engine is inadvertently flooded or over primed, turn the ignition switchoff and move the throttle to the “full open” position. To rid the engine of the excess fuel,turn it over by hand or by the starter. If excessive force is needed to turn over the engine,stop immediately. Do not force rotation of the engine. If in doubt, remove the lowercylinder spark plugs. If very serious overloading has occurred, it may be necessary toremove the lower cylinder intake pipes. To reduce the likelihood of damage to the enginedue to over priming on some medium and large aircraft, the engine blower drain valvesshould be checked frequently for fouling or sticking.

Immediately after the engine starts, check the oil pressure indicator. If oil pressure doesnot show within 30 seconds, stop the engine and determine the trouble. If oil pressure isindicated, adjust the throttle to the aircraft manufacturer’s specified rpm for enginewarmup. Warmup rpm will usually be in the 1,000 to 1,300 rpm range.

Most aircraft reciprocating engines are air cooled and depend on the forward speed of theaircraft to maintain proper cooling. Therefore, particular care is necessary when operatingthese engines on the ground.

During all ground running, operate the engine with the propeller in full low pitch and headedinto the wind with the cowling installed to provide the best degree of engine cooling. Theengine instruments should be monitored closely at all times. Do not close the cowl flapsfor engine warmup; closing of the cowl flaps may cause the ignition harness to overheat.When warming up the engine, make sure that personnel, ground installations, equipment



that may be damaged, or other aircraft are not in the propeller wash.

Extinguishing Engine Fires

In all cases a fireguard should stand by with a CO2 fire extinguisher while the aircraftengine is being started. This is a necessary precaution against fire during the startingprocedure. He should be familiar with the induction system of the engine so that in case offire he can direct the CO2 into the air intake of the engine to extinguish it. A fire could alsooccur in the exhaust system of the engine from liquid fuel being ignited in the cylinder andexpelled during the normal rotation of the engine. If an engine fire develops during thestarting procedure, continue cranking to start the engine and blow out the fire. If the enginedoes not start and the fire continues to burn, discontinue the start attempt. The fireguardshould extinguish the fire using the available equipment. The fireguard must observe allsafety practices at all times while standing by during the starting procedure.

TURBOPROP ENGINES

Prestart Procedures

The various covers protecting the aircraft must be removed. Engine tailpipes should becarefully inspected for the presence of fuel or oil. A close visual inspection of allaccessible parts of the engines and engine controls should be made, followed by aninspection of all nacelle areas to determine that all inspection and access plates aresecured. Sumps should be checked for water. Air inlet areas should be inspected forgeneral condition and foreign material. The compressor should be checked for freerotation, when the installation permits, by reaching in and turning the blades by hand.

The following procedures are typical of those used to start turboprop engines. There are,however, wide variations in the procedures applicable to the many turboprop engines, andno attempt should be made to use these procedures in the actual starting of a turbopropengine. These procedures are presented only as a general guide for familiarization withtypical procedures and methods. For starting of all turboprop engines, refer to the detailedprocedures contained in the applicable manufacturer’s instructions or their approvedequivalent.

The first step in starting a turbine engine is to provide an adequate source of power for thestarter. Where an air turbine starter is used, the starting air supply may be obtained from agas turbine compressor (GTC), an external source, or an engine crossbleed operation. Tostart the first engine, use a GTC or low pressure, large volume tank. Start the remainingengine(s) using bleed air from the running engine.

While starting an engine, always observe the following:

1. Never energize the starter while the engine is rotating.2. Do not move the power lever of any engine while it is being bled for crossbleed starting.3. Do not perform a ground start if turbine inlet temperature is above that specified by the



manufacturer.4. Do not use bleed air from an engine that is accelerating.

Starting Procedures

To start an engine on the ground, perform the following operations:

1. Place the start selector switch to the desired engine and the start arming switch (if soequipped) to the “start” position.

2. Turn the aircraft boost pumps on.

3. Place the fuel and ignition switch on.

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

5. Make sure that the power lever is in the “start” position. If the propeller is not at the“start” position, difficulty may be encountered in making a start.

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

7. Make sure the fuel pump parallel light comes on at, or above, 2,200 rpm and remains onup to 9,000 rpm.

8. Check the oil pressure and temperature. Maintain the power lever at the “start” positionuntil the specified minimum oil temperature is reached.

9. Disconnect the ground power supply.

If any of the following conditions occur during the starting sequence, turn off the fuel andignition switch, discontinue the start immediately, make an investigation and record thefindings.

1. Turbine inlet temperature exceeds the specified maximum. Record the observed peaktemperature.

2. Acceleration time from start of propeller rotation to stabilized rpm exceeds the specifiedtime.

3. There is no oil pressure indication at 5,000 rpm for either the reduction gear or thepower unit.

4. Torching (visible burning in the exhaust nozzle other than normal enrichment) orexcessive smoke is observed during initial fire up.

5. The engine fails to ignite by 4,500 rpm or maximum motoring rpm (whichever is first),



and rpm stagnates or begins to decay.

6. Abnormal vibration is noted or compressor surge occurs (indicated by backfiring).

7. There is fuel spewing from the nacelle drain, indicating that the drip valve did not close.

8. Fire warning bell rings. (This may be due to either an engine fire or failure of an antiicing shutoff valve to close.)

TURBOJET ENGINES

Preflight Operations

Unlike reciprocating engine aircraft, the turbojet powered aircraft does not require a preflight runup unless it is necessary to investigate a suspected malfunction. Before starting,all protective covers and air inlet duct covers should be removed. If possible, the aircraftshould be headed into the wind to obtain better cooling, faster starting, and smootherengine performance. It is especially important that the aircraft be headed into the wind ifthe engine is to be trimmed.

The runup area around the aircraft should be cleared of both personnel and looseequipment.

The turbojet engine intake and exhaust hazard areas are illustrated in figure 111. Careshould also be taken to ensure that the runup area is clear of all items such as nuts,bolts, rocks, rags, or other loose debris.

A great number of very serious accidents occur involving personnel in the vicinity ofturbojet engine air inlets. Extreme caution should be exercised when starting turbojetaircraft.

The aircraft fuel sumps should be checked for water or ice, and the engine air inlet shouldbe inspected for general condition and the presence of foreign objects. The forwardcompressor blades and the compressor inlet guide vanes should be visually inspected fornicks and other damage.

If possible, the compressor should be checked for free rotation by turning the compressorblades by hand.

All engine controls should be operated, and engine instruments and warning lights shouldbe checked for proper operation.

Starting a Turbojet Engine

The following procedures are typical of those used to start many turbojet engines. Thereare, however, wide variations in the starting procedures used for turbojet engines, and no



attempt should be made to use these procedures in the actual starting of an engine. Theseprocedures are presented only as a general guide for familiarization with typicalprocedures and methods. In the starting of all turbojet engines, refer to the detailedprocedures contained in the applicable manufacturer’s instructions or their approvedequivalent.

Most turbojet engines can be started by either air turbine or combustiontype starters. Airturbine starters use compressed air from an external source. This source may be a groundcart unit or air bled from another engine on the aircraft that is in operation. Combustionstarters are small gas turbine engines that obtain power from expanding gases generatedin the starter’s combustion chamber. These hot gases are produced by the burning of fueland air or, in some cases, a slow burning solid or liquid monopropellant speciallycompounded for such starter units.

Fuel is turned on either by moving the power lever to “idle” position or by opening a fuelshutoff valve. If an air turbine starter is used, the engine should start or “light up” withinapproximately 20 seconds after the fuel is turned on. This is an arbitrarily chosen timeinterval that, if exceeded, indicates a malfunction has occurred and the start should bediscontinued. After the cause of the trouble has been removed, another start may bemade. If a combustion starter is used, the 20 second interval need not be observed, sincestarter operation will discontinue automatically after a predetermined time interval. Thefollowing procedures are useful only as a general guide, and are included to show thesequence of events in starting a turbojet engine.

1. Move power lever to “off” position unless the engine is equipped with thrust reverser. Ifthe engine is so equipped, place the power lever in the “idle” position.2. Turn on electrical power to engine.3. Turn fuel system shutoff switch to “fuel on” position.4. Turn fuel boost pump switch on.5. A fuel inlet pressure indicator reading of 5 psi ensures fuel is being delivered to enginefuel pump inlet.6. Turn engine starter switch on; when engine begins to rotate, check for oil pressure rise.7. Turn ignition switch on after engine begins to rotate.8. Move throttle to idle (if engine is not equipped with thrust reverser).9. Engine start (light up) is indicated by a rise in exhaust gas temperature.10. After engine stabilizes at idle, ensure that none of the engine limits are exceeded.11. Turn engine starter switch off after start.12. Turn ignition switch off.

Unsatisfactory Turbojet Starts

1. Hot Starts.

A hot start occurs when the engine starts, but the exhaust gas temperature exceedsspecified limits. This is usually caused by an excessively rich fuel/air mixture entering thecombustion chamber. The fuel to the engine should be shut off immediately.



2. False or Hung Start.

False or hung starts occur when the engine starts normally but the rpm remains at somelow value rather than increasing to the normal starting rpm. This is often the result ofinsufficient power to the starter, or the starter cutting off before the engine starts selfaccelerating. In this case, the engine should be shut down.

3. Engine Will Not Start.

The engine will not start within the prescribed time limit. It can be caused by lack of fuelto the engine, insufficient or no electrical power, or malfunctions in the ignition system. Ifthe engine fails to start within the prescribed time, it should be shut down.

In all cases of unsatisfactory starts the fuel and ignition should be turned off. Continuerotating the compressor for approximately 15 seconds to remove accumulated fuel fromthe engine. If unable to motor (rotate) the engine, allow a 30 second fuel draining periodbefore attempting another start.

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