IGNITION AND STARTING SYSTEMS A&P FAA

8503: When a magneto is disassembled, keepers are usually placed across poles of the rotating magnet to reduce loss of magnetism. These keepers are usually made of. Soft iron. Soft iron.

8504: How is the strength of a magneto magnet checked?. Hold the points open and check the output of the primary coil with an AC ammeter while operating the magneto at a specified speed. Hold the points open and check the output of the primary coil with an AC ammeter while operating the magneto at a specified speed.

8505: The E-gap angle is usually defined as the number of degrees between the neutral position of the rotating magnet and the position. where the contact points open. where the contact points open.

8506: The greatest density of flux lines in the magnetic circuit of a rotating magnet-type magneto occurs when the magnet is in what position?. Full alignment with the field shoe faces. Full alignment with the field shoe faces.

8507: Magneto breaker point opening relative to the position of the rotating magnet and distributor rotor (internal timing) can be set most accurately. during assembly of the magneto before installation on the engine. during assembly of the magneto before installation on the engine.

8508: Why are high-tension ignition cables frequently routed from the distributors to the spark plugs in flexible metallic conduits?. To reduce the effect of the high-frequency electromagnetic waves emanated during operation. To reduce the effect of the high-frequency electromagnetic waves emanated during operation.

8509: What will be the results of increasing the gap of the breaker points in a magneto?. Advance the spark and decrease the intensity. Advance the spark and decrease the intensity.

8510: What is the purpose of a safety gap in some magnetos?. To discharge the secondary coil's voltage if an open occurs in the secondary circuit. To discharge the secondary coil's voltage if an open occurs in the secondary circuit.

8511: When timing a magneto internally, the alignment of the timing marks indicates that the. magnets are in the E-gap position. magnets are in the E-gap position.

8512: When internally timing a magneto, the breaker points begin to open when the rotating magnet is. a few degrees past the neutral position. a few degrees past the neutral position.

8512-2: Magneto timing drift is caused by erosion of the breaker points and. wear of the cam followers. wear of the cam followers.

8513: What is the electrical location of the primary capacitor in a high-tension magneto?. In parallel with the breaker points. In parallel with the breaker points.

8514: In a high-tension ignition system, the current in the magneto secondary winding is. induced when the primary circuit is interrupted. induced when the primary circuit is interrupted.

8515: When a "Shower of Sparks" ignition system is activated at an engine start, a spark plug fires. only while both the retard and advance breaker points are open. only while both the retard and advance breaker points are open.

8516: What is the radial location of the two north poles of a four-pole rotating magnet in a high-tension magneto?. 180° apart. 180° apart.

8517: Magneto pole shoes are generally made of. laminations of high-grade soft iron. laminations of high-grade soft iron.

8518: Capacitance afterfiring in most modern spark plugs is reduced by the use of. a built-in resistor in each plug. a built-in resistor in each plug.

8519: What components make up the magnetic system of a magneto?. Rotating magnet, the pole shoes, the pole shoe extension and the coil core. Rotating magnet, the pole shoes, the pole shoe extension and the coil core.

8520: In an aircraft ignition system, one of the functions of the capacitor is to. facilitate a more rapid collapse of the magnetic field in the primary coil. facilitate a more rapid collapse of the magnetic field in the primary coil.

8521: When the voltage in the secondary winding of a magneto, installed on a normally operating engine, be at its highest value?. Just prior to spark plug firing. Just prior to spark plug firing.

8522: When the switch is off in a battery ignition system, the primary circuit is. opened. opened.

8523: As an aircraft engine's speed is increased, the voltage induced in the primary coil of the magneto. increases. increases.

8524: When internally timing a magneto, the breaker points begin to open when. the magneto poles are a few degrees beyond the neutral position. the magneto poles are a few degrees beyond the neutral position.

8525: The purpose of a safety gap in a magneto is to. protect the high-voltage winding from damage. protect the high-voltage winding from damage.

8526: A defective primary capacitor in a magneto is indicated by. burned and pitted breaker points. burned and pitted breaker points.

8527: How many secondary coils are required in a low-tension ignition system on an 18-cylinder engine?. 36. 36.

8528: A magneto ignition switch is connected. parallel to the breaker points. parallel to the breaker points.

8529: The spark is produced in a magneto ignition system when the breaker points are. beginning to open. beginning to open.

8530: Shielding is used on spark plug and ignition wires to. prevent interference with radio reception. prevent interference with radio reception.

8531: What is the purpose of using an impulse coupling with a magneto?. To produce a momentary high rotational speed of the magneto. To produce a momentary high rotational speed of the magneto.

8532: The purpose of staggered ignition is to compensate for. diluted fuel/air mixture around exhaust valve. diluted fuel/air mixture around exhaust valve.

8533: Aircraft magneto housings are usually ventilated in order to. provide cooling and remove corrosive gases produced by normal arcing. provide cooling and remove corrosive gases produced by normal arcing.

8534: Failure of an engine to cease firing after turning the magneto switch off is an indication of. an open P-lead to ground. an open P-lead to ground.

8535: Alignment of the marks provided for internal timing of a magneto indicates that the. magneto is in E-gap position. magneto is in E-gap position.

8536: When using a timing light to time a magneto to an aircraft engine, the magneto switch should be placed in the. BOTH position. BOTH position.

8537: What is the difference between a low-tension and a high-tension engine ignition system?. A low-tension system uses a transformer coil near the spark plugs to boost voltage, while the high-tension system voltage is constant from the magneto to the spark plugs. A low-tension system uses a transformer coil near the spark plugs to boost voltage, while the high-tension system voltage is constant from the magneto to the spark plugs.

8538: What test instrument could be used to test an ignition harness for suspected leakage?. A high tension lead tester. A high tension lead tester.

8539: The amount of voltage generated in any magneto secondary coil is determined by the number of windings and by the. rate of collapse of the magnetic field round the primary coil. rate of collapse of the magnetic field round the primary coil.

8540: Magneto breaker points must be times to open when the. greatest magnetic field stress exists in the magnetic circuit. greatest magnetic field stress exists in the magnetic circuit.

8541: In reference to a "Shower of Sparks" ignition system, (1) the retard breaker points are designed to keep the affected ignition system operating if the advance breaker points should fail during normal engine operation (after start) (2) the timed opening of the retard breaker points is designed to prevent engine "kickback" during start. Regarding the above statements,. only No. 2 is true. only No. 2 is true.

8542: The capacitor-type ignition system is used almost universally on turbine engines primarily because of its high voltage and. high-heat intensity. high-heat intensity.

8543: In a low tension ignition system, each spark plug requires individual. secondary coil. secondary coil.

8544: A certain nine-cylinder radial engine used a non-compensated single-unit, dual-type magneto with a four pole rotating magnet and separately mounted distributors. Which of the following will have the lowest RPM at any given engine speed?. Distributors. Distributors.

8545: What will be the effect if the spark plugs are gapped too wide?. Hard starting. Hard starting.

8546: When removing a shielded spark plug, which of the following is most likely to be damaged?. Core insulator. Core insulator.

8547: What likely effect would a cracked distributor rotor have on a magneto?. Ground the secondary coil through the crack. Ground the secondary coil through the crack.

8548: How does the ignition system of a gas turbine engine differ from that of a reciprocating engine?. A high-energy spark is required for ignition. A high-energy spark is required for ignition.

8549: In a turbine engine DC capacitor discharge ignition system, where are the high-voltage pulses formed?. At the triggering transformer. At the triggering transformer.

8550: Which of the following breaker point characteristics is associated with a faulty capacitor?. Coarse grained. Coarse grained.

8551: How are most radial engine spark plug wires connected to the distributor block?. By use of the cable-piercing screws. By use of the cable-piercing screws.

8552: Thermocouples are usually inserted or installed on the. hottest cylinder of the engine. hottest cylinder of the engine.

8553: Capacitance afterfiring of a spark plug is caused by. the stored energy in the ignition shielded lead unloading after normal timed ignition. the stored energy in the ignition shielded lead unloading after normal timed ignition.

8554: If it is found that a shielded ignition system does not adequately reduce ignition noise, it may be necessary to install. a filter between the magneto and magneto switch. a filter between the magneto and magneto switch.

8555: When a magneto is operating, what is the probable cause for a shift in internal timing?. The cam follower wear and/or breaker points wear. The cam follower wear and/or breaker points wear.

8556: Why are turbine engine igniters less susceptible to fouling than reciprocating engine spark plug?. The high-intensity spark cleans igniter. The high-intensity spark cleans igniter.

8557: The constrained-gap igniter plug used in some gas turbine engines operates at a cooler temperature because. The construction is such that the spark occurs beyond the face of the combustion chamber liner. The construction is such that the spark occurs beyond the face of the combustion chamber liner.

8558: What should be used to clean grease or carbon tracks from capacitors or coils that are used in magnetos?. Acetone. Acetone.

8559: Generally, when removing a turbine engine igniter plug, in order to eliminate the possibility of the technician receiving a lethal shock, the ignition switch is turned off and. the igniter lead is disconnected from the plug and the center electrode grounded to the engine after disconnecting the transformer-exciter input lead and waiting the prescribed time. the igniter lead is disconnected from the plug and the center electrode grounded to the engine after disconnecting the transformer-exciter input lead and waiting the prescribed time.

8560: Great caution should be exercised in handling damaged hermetically sealed turbine engine igniter transformer units because. some contain radioactive material. some contain radioactive material.

8561: Igniter plugs used in turbine engines are subjected to high intensity spark discharges and yet they have a long service life because they. do not require continuous operation. do not require continuous operation.

8562: The electrical circuit from the spark plug back to the magneto is completed by grounding through the. engine structure. engine structure.

8563: Spark plugs are considered worn out when the. electrodes have worn away to about one-half of their original dimensions. electrodes have worn away to about one-half of their original dimensions.

8564: Which of the following could cause damage to the nose ceramic or to the electrode of an aircraft spark plugs?. Improper gapping procedure. Improper gapping procedure.

8565: Sharp bends should be avoided in ignition leads primarily because. weak points may develop in the insulation through which high tension current can leak. weak points may develop in the insulation through which high tension current can leak.

8566: In a high-tension ignition system, a primary capacitor of too low a capacity. the breaker contacts burn. the breaker contacts burn.

8567: Which of the following, obtained during magneto check at 1,700 RPM, indicates a short (grounded) circuit between the right magneto primary and the ignition switch?. BOTH- 1,700 RPM, R- 0 RPM, L- 1,700 RPM, OFF- 0 RPM. BOTH- 1,700 RPM, R- 0 RPM, L- 1,700 RPM, OFF- 0 RPM.

8568: If an aircraft ignition switch s turned off and the engine continues to run normally, the trouble is probably caused by. an open ground lead in the magneto. an open ground lead in the magneto.

8569: Which statement is correct regarding the ignition system of a turbine engine?. The system is normally de-energized as soon as the engine starts. The system is normally de-energized as soon as the engine starts.

8570: When the ignition switch of a single (reciprocating) engine aircraft is turned to the OFF position. the primary circuits of both magnetos are grounded. the primary circuits of both magnetos are grounded.

8571: A spark plug's heat range is the result of. its ability to transfer heat from the firing end of the spark plug to the cylinder head. its ability to transfer heat from the firing end of the spark plug to the cylinder head.

8572: If staggered ignition timing is used, the. spark plug nearest the exhaust valve will fire first. spark plug nearest the exhaust valve will fire first.

8573: The term "reach" as applied to spark plug design and/or type, indicates the. linear distance from the shell gasket seat to the end of the threads on the shell skirt. linear distance from the shell gasket seat to the end of the threads on the shell skirt.

8574: The numbers appearing on the ignition distributor block indicate the. sparking order of the distributor. sparking order of the distributor.

8575: When testing a magneto distributor block for electrical leakage, which of the following pieces of test equipment should be used?. a high-tension harness tester. a high-tension harness tester.

8576: (1) The platinum and iridium ground electrodes used on fine wire spark plugs are extremely brittle and can be broken if they are improperly handled or adjusted. (2) When gapping massive-electrode spark plugs, a wire gauge should be inserted between the center and ground electrodes while moving the ground electrode in order to avoid setting the gap too close. Regarding the above statements. only No. 1 is true. only No. 1 is true.

8577: Hot spark plugs are generally used in aircraft powerplants. with comparatively low operating temperatures. with comparatively low operating temperatures.

8578: If a spark plug lead becomes grounded, the. magneto will not be affected. magneto will not be affected.

8579: Which of the following statements regarding magneto switch circuits is NOT true?. In the BOTH position, the right and left magneto circuits are grounded. In the BOTH position, the right and left magneto circuits are grounded.

8580: Which of the following statements most accurately describes spark plug heat range?. A cold plug is designed so that the insulator tip is reasonably short to hasten the rate of heat transfer from the tip through the spark plug shell to the cylinder head. A cold plug is designed so that the insulator tip is reasonably short to hasten the rate of heat transfer from the tip through the spark plug shell to the cylinder head.

8581: When does battery current flow through the primary circuit of a battery ignition coil?. When the breaker points are closed and the ignition switch is on. When the breaker points are closed and the ignition switch is on.

8582: In order to turn a magneto off, the primary circuit must be. grounded. grounded.

8583: When performing a magneto ground check on an engine, correct operation is indicated by. a slight drop in RPM. a slight drop in RPM.

8584: Defective spark plugs will cause the engine to run rough at. all speeds. all speeds.

8585: A spark plug is fouled when. its spark grounds without jumping electrodes. its spark grounds without jumping electrodes.

8586: Which of the following would be cause for rejection of a spark plug?. Insulator tip cracked. Insulator tip cracked.

8587: What will be the result of using too hot a spark plug. Preignition. Preignition.

8588: Upon inspection of the spark plugs in an aircraft engine, the plugs were found caked with a heavy black soot. This indicates. a rich mixture. a rich mixture.

8589: Spark plug heat range is determined by. its ability to transfer heat to the cylinder head. its ability to transfer heat to the cylinder head.

8590: Ignition check during engine runup indicates excessive RPM drop during operation on the right magneto. The major portion of the RPM loss occurs rapidly after switching to the right magneto position (fast drop). The mostly likely cause is. faulty or fouled spark plugs. faulty or fouled spark plugs.

8591: If new breaker points are installed in a magneto on an engine, it will be necessary to time the. magneto internally and the magneto to the engine. magneto internally and the magneto to the engine.

8592: Using a cold spark plug in a high-compression aircraft engine would probably result in. normal operation. normal operation.

8593: Spark plug fouling caused by lead deposits occurs most often. when cylinder head temperatures are relatively low. when cylinder head temperatures are relatively low.

8594: In a four-stroke cycle aircraft engine, when does the ignition event take place?. Before the piston reaches TDC on compression stroke. Before the piston reaches TDC on compression stroke.

8595: When installing a magneto on an engine, the. piston in the No. 1 cylinder must be prescribed number of degrees before top center on the compression stroke. piston in the No. 1 cylinder must be prescribed number of degrees before top center on the compression stroke.

8596: The spark occurs at the spark plug when the ignition's. primary circuit is broken. primary circuit is broken.

8597: The type of ignition system used on most turbine aircraft engines is. capacitor discharge. capacitor discharge.

8598: Ignition check during engine runup indicates a slow drop in RPM. This is usually caused by. incorrect ignition timing or valve adjustment. incorrect ignition timing or valve adjustment.

8599: If the ground wire of a magneto is disconnected at the ignition switch, the result will be the. engine will not stop running when the ignition switch is turned off. engine will not stop running when the ignition switch is turned off.

8600: Which of the following are advantages of dual ignition in aircraft engines? (1) Gives a more complete and quick combustion of the fuel. (2) Provides backup magneto system. (3) Increases the power output of the engine. (4) Permits the use of lower grade fuels. (5) Increases burn intensity of the spark at the spark plugs. 1, 2, 3. 1, 2, 3.

8601: How does high-tension ignition shielding tend to reduce radio interference?. Receives and grounds high-frequency waves coming from the magneto and high-tension ignition leads. Receives and grounds high-frequency waves coming from the magneto and high-tension ignition leads.

8602: Which of the following are distinct circuits of a high-tension magneto? (1) Magnetic (2) Primary (3) E-gap (4) P-Lead (5) Secondary. 1, 2, 5. 1, 2, 5.

8603: What are two parts of a distributor in an aircraft engine ignition system? (1) Coil (2) Block (3) Stator (4) Rotor (5) Transformer. 2 and 4. 2 and 4.

8604: What is a result of "flashover" in a distributor?. Conductive carbon trail. Conductive carbon trail.

8605: What is the relationship between the distributor and crankshaft speed of aircraft reciprocating engines?. The distributor turns at one-half crankshaft speed. The distributor turns at one-half crankshaft speed.

8606: Why do turbine engine ignition systems require high energy?. To ignite the fuel under conditions of high altitude and low temperatures. To ignite the fuel under conditions of high altitude and low temperatures.

8607: Which of the following are included in a typical turbine engine ignition system? (1) two igniter plugs (2) two transformers (3) one exciter unit (4) two intermediate ignition leads (5) two low tension igniter leads (6) two high tension igniter leads. 1, 3, 6. 1, 3, 6.

8608: At what RPM is a reciprocating engine ignition switch check made?. The slowest possible RPM. The slowest possible RPM.

8609: What is the approximate position of the rotating magnet in a high-tension magneto when the points first close?. Full register. Full register.

8610: What component of a dual magneto is shared by both ignition systems?. Rotating magnet. Rotating magnet.

8611: What would be the result if a magneto breaker point mainspring did not have sufficient tension?. The points will float or bounce. The points will float or bounce.

8612: The secondary coil of a magneto is grounded through the. primary coil. primary coil.

8613: In the aircraft magneto system, if the P-lead is disconnected, the magneto will be. on regardless of ignition switch position. on regardless of ignition switch position.

8614: (Refer to Figure 5) With power applied to the bus bar, what wire supplies standby power to the starter relay contact?. 4. 4.

8615: (Refer to Figure 5) With power applied to the bus bar, what switch changes will allow the ignition exciters test switch to function?. Engine master switch and ignition switch. Engine master switch and ignition switch.

8616: (Refer to Figure 5) The type of system depicted is capable of operating with. either battery or external power. either battery or external power.

8617: (Refer to Figure 5) If wire No. 8 is broken or disconnected after starter rotation is initiated, and the power lever is advanced. starting sequence will continue normally. starting sequence will continue normally.

8618: (Refer to Figure 5) When an external power source is connected to the aircraft. the battery cannot be connected to the bus. the battery cannot be connected to the bus.

86219: The purpose of an under current relay in a starter-generator system is to. disconnect power from the starter-generator and ignition when sufficient engine speed is reached. disconnect power from the starter-generator and ignition when sufficient engine speed is reached.

8620: In a typical starter-generator system, under which of the following starting circumstances may it be necessary to use the start stop switch?. Hung start. Hung start.

8621: (Refer to Figure 5) Which malfunctions will allow the igniters to operate when tested but be inoperative during a start attempt? (1) Conductor No. 10 broken (2) Conductor No. 11 broken (3) Ignition relay inoperative (4) Conductor No. 12 broken. 1 or 3. 1 or 3.

8622: (Refer to Figure 5) Which malfunctions will allow the igniters to operate normally during start but be inoperative when tested? (1) conductor No. 14 broken (2) conductor No. 10 broken (3) Conductor No. 15 broken (4) Conductor No. 12 broken. 1 or 3. 1 or 3.

8623: When using an electric starter motor, current usage. is highest at the start of motor rotation. is highest at the start of motor rotation.

8624: When using an electric starter motor, the current flow through it. is highest at the start of motor rotation. is highest at the start of motor rotation.

8625: The primary advantage of pneumatic (air turbine) starters over comparable electric starters for turbine engines is. high power-to-weight ratio. high power-to-weight ratio.

8626: A clicking sound can be heard at engine coast-down in a pneumatic starter incorporating a sprag clutch ratchet assembly is an indication of. the pawls recontacting and riding on the ratchet gear. the pawls recontacting and riding on the ratchet gear.

8627: Pneumatic starters are usually designed with what types of airflow impingement systems?. Radial inward flow turbine and axial-flow turbine. Radial inward flow turbine and axial-flow turbine.

8628: Inspection of pneumatic starters by maintenance technicians usually includes checking the. oil level and magnetic drain plug condition. oil level and magnetic drain plug condition.

8629: Air turbine starters are generally designed so that reduction gear distress or damage may be detected by. inspection of a magnetic chip detector. inspection of a magnetic chip detector.

8630: Airflow to the pneumatic starter from a ground unit is normally prevented from causing starter overspeed during engine start by. activation of a flyweight cutout switch. activation of a flyweight cutout switch.

8631: A safety feature usually employed in pneumatic starters that is used if the clutch does not release from the engine drive at the proper time during start is the. drive shaft shear point. drive shaft shear point.

8632: A safety feature usually employed in direct-cranking starters that is used to prevent the starter from reaching burst speed is the. stator nozzle design that chokes airflow and stabilizes turbine wheel speed. stator nozzle design that chokes airflow and stabilizes turbine wheel speed.

8633: In the event a pneumatic start valve will not operate and the manual override must be used, the starter T-handle must be closed at scheduled starter drop out because. the starter will overspeed at a given N2. the starter will overspeed at a given N2.