AP Powerplant Oral Questions, ASA-OEG-

A&P Powerplant Oral Questions, ASA-OEG- AMT2 Latest Update - Actual Exam 250 Questions and 100% Verified Correct Answers Guaranteed A+

Are the instruments installed in an aircraft suitable for use when trimming a turbine

engine? - CORRECT ANSWER: No a special analyzer/trimmer such as a JetCal should

be used.

Do the counterweights on a propeller tend to move the blades toward high pitch or

toward low pitch? - CORRECT ANSWER: Toward high pitch.

Does a turbine engine controlled by a FADEC require manual trimming? - CORRECT

ANSWER: No, this is done by the FADEC.

Does centrifugal twisting moment on a propeller blade tend to move the blades toward

high pitch or toward low pitch? - CORRECT ANSWER: Toward low pitch

Does the application of carburetor heat cause the fuel-air mixture to become richer or

leaner? - CORRECT ANSWER: The less dense, heated air draws the same amount of

fuel from the carburetor as cold air, therefore the mixture becomes richer.

How are electrical wires protected where they passed through an area of high

temperature? - CORRECT ANSWER: Wires passing through these areas are insulated

with high temperature insulation, and the wires are enclosed in some type of protective conduit.

How are propellers on a twin-engine airplane synchronized? - CORRECT ANSWER:

The propeller governor of the master engine is set to the desired RPM. A signal from the mastered engine governor is sent to the control box which sends a signal to a stepping motor. This motor adjust the propeller governor and fuel control of the slave engine causing it to maintain exactly the same RPM as the master engine.

How are small nicks removed from the leading edge of the propeller blade? - CORRECT ANSWER: File them out with a fine file or stone, leaving a smooth Contor.

How can you check an exhaust system for leaks? - CORRECT ANSWER: Pressurize

the exhaust system with the discharge from a vacuum cleaner and wipe a soap solution over all joints and suspect areas. A leak will cause bubbles to form.

how can you determine that a surface scratch in an aluminum alloy propeller blade is

not actually a crack? - CORRECT ANSWER: Clean the damage out to a saucer shaped

depression and spray the area with a die penetrant liquid. Allow it time to seep into a crack if one is present, then wipe all of the liquid off of the surface. Spray the area with 1 / 3

the developer. If the damage is actually a crack, the developer will pull the penetrant out and it will form a visible line.

How can you determine that the electrically heated deicer boots on the propeller blades

are working as they should? - CORRECT ANSWER: Observe the load meter or

ammeter to see if the proper current is flowing, and follow the sequence of boot heating by feeling with your hands to see which one is heating. The boots should all have a similar heat rise in the same length of time.

How can you determine the firing order of an 18 cylinder radial engine? - CORRECT

ANSWER: Begin with cylinder 1, add 11 and subtract 7, whichever will keep the

numbers between 1 and 18. 1-12 - 5-16 - 9-2 - 13-6 - 17-10 - 3-14 - 7-18 - 11-4 - 15-8

How do the components in the exhaust system of a turbocharged engine allow for expansion and contraction due to heat, and at the same time prevent leakage? -

CORRECT ANSWER: Bellows and ball joints prevent leakage while allowing

contraction and expansion.

How do you check a thermocouple fire detection system for operation? - CORRECT ANSWER: Press the test switch. This heats the test thermocouple enough for it to close the sensitive relay, which in turn closes the slave relay and activates the fire warning light and Bell.

How does a cascade type thrust reverser operate? - CORRECT ANSWER: A portion of

the fan cowl moves rearward, and a series of blocker doors deflect the fan discharge air through fan cascades that direct the discharge air forward. At the same time, blocker door shut off the flow of gases from the core engine and deflect it through cascades that direct it forward.

How does a leak appear in an engine exhaust system? - CORRECT ANSWER: It

normally looks like a gray or black feather-shaped streak coming from a crack or from a location where components are not in perfect alignment.

How does a ratiometer-type oil temperature gauge measure the temperature of the oil?

- CORRECT ANSWER: A ratiometer measures the resistance of the temperature bulb.

The indicator is calibrated in degrees Fahrenheit or Celsius rather than in ohms.

How is a high rate discharge bottle of fire extinguishing agent discharged? - CORRECT ANSWER: A powder charge is ignited and it blows a cutter through a frangible disc that seals the bottle.

How is a pneumatic-type continuous-loop fire detection system checked for operation? - CORRECT ANSWER: When the test switch is closed, low voltage AC flows through the tube that encloses the sensitive element. This current heats the element enough for it to release sufficient gas to activate the alarm switch.

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How is hydraulic lock removed from an aircraft engine? - CORRECT ANSWER:

Remove a spark plug from the locked cylinder and drain all of the oil out. Clean the spark plug and replace it.

How is ice prevented from forming on propeller blades? - CORRECT ANSWER: A

chemical anti-icing system is used. A mixture of isopropyl alcohol and ethylene glycol is pumped into a slinger ring on the back of the propeller hub. From there centrifugal force slings it out along the blades. Ice cannot form on the resulting slick surface

How is ice prevented from forming on the nose cowl, nose dome and inlet guide veins of

a turbine engine? - CORRECT ANSWER: Hot compressor bleed air flows through

passages in these components to keep them too warm for ice to form.

How is ice removed from propeller blades? - CORRECT ANSWER: An electrothermal

deicing system is used. Electrical heating elements are embedded in rubber boots that are bonded to the leading edges of the blades. Low-voltage DC flows from the propeller deicer control through brushes and slip rings to the heating elements. The timer sends current to one propeller for about 90 seconds and then to the other for the next 90 seconds. This allows the ice to form and then break loose and blow away.

How is most of the troubleshooting done for a modern APU? - CORRECT ANSWER: By

the fault codes generated by the FADEC.

How is oil pressure regulated in an aircraft engine? - CORRECT ANSWER: A relief

valve senses the desired pressure and sends all of the oil that causes excessive pressure back into the engine sump.

How is the direction of rotation of a DC electric motor reversed? - CORRECT ANSWER: Reverse the polarity of the Armature or the field, but not both.

How is the strength of the magnet in a magneto checked? - CORRECT ANSWER: The

magnetos put on a test stand and rotated at a specified speed. The breaker points are held open and the primary current is measured. The strength of the magnet determines the amount of primary current.

How many igniters are used in most turbine engines? - CORRECT ANSWER: Two

If there is a break in a single wire continuous loop fire detector element, and the system

tests bad, will it indicate the presence of a fire? - CORRECT ANSWER: Yes, even

though it tests bad, it will still indicate the presence of a fire.

In what position is the magnet in a magneto when the breaker points begin to open? -

CORRECT ANSWER: In its E-gap position, just a few degrees beyond its neutral

position.

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