Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
31 Cards in this Set
- Front
- Back
The primary purpose of baffles and deflectors installed around cylinders of air-cooled aircraft engines is to A - create a low pressure area aft of the cylinders B - force cooling air into close contact with all parts of the cylinders C - increase the volume of air used to cool the engine |
B - force cooling air into close contact with all parts of the cylinders |
|
What is the purpose of an augmenter used in some reciprocating engine exhaust systems? A - to reduce exhaust back pressure B - to aid in cooling the engine C - to assist in displacing the exhaust gases |
B - to aid in cooling the engine |
|
Aircraft reciprocating engine cylinder baffles and deflectors should be repaired as required to prevent loss of A - power B - fin area C - cooling |
C - cooling |
|
Cracks in cooling fins that do not extend into the cylinder head may be repaired by A - fill in the extremities of crack with liquid metal B - removing affected area and contour filling within limits C - welding and then grinding or filling to original thickness |
B - removing affected area and contour filling within limits |
|
Which of the following should a mechanic consult to determine the maximum amount of cylinder cooling fin that could be removed when cracks are found? A - AC 43.13-1A B - engine manufacturer's service or overhaul manual C - engine structure repair manual |
B - engine manufacturer's service or overhaul manual |
|
A bent cooling fin on an aluminum cylinder head A - should be sawed off and filed smooth B - should be left alone if no crack has formed C - should be stop drilled or a small radius filed at the point of the bend |
B - should be left alone if no crack has formed |
|
Where are the cooling fins usually located on air-cooled engines? A - exhaust side of the cylinder head, inside the pistons, and connecting rods B - cylinder head, cylinder walls, and inside the piston C - cylinder head, cylinder barrel, and inside the piston |
C - cylinder head, cylinder barrel, and inside the piston |
|
How do cowl flaps aid in cooling a horizontally opposed aircraft engine? A - recirculates air through the engine cylinders B - directs air through the engine cylinders C - controls the amount of air flowing around the cylinders |
C - controls the amount of air flowing around the cylinders |
|
The positive of the cowl flaps during normal cruise flight conditions is A - closed B - open C - one half open |
A - closed |
|
Generally, a small crack just started in a cylinder baffle A - requires repair by reinforcing, such as installation of a double over the area B - requires no action unless it grows or is branched into two cracks C - may be stop drilled |
C - may be stop drilled |
|
Which of the following assists in removing heat from the metal walls and finds of an air-cooled cylinder assembly? A - an intercooler system B - a baffle and cowl arrangement C - an engine induction system |
B - a baffle and cowl arrangement |
|
During ground operation of an engine, the cowl flaps should be in what position? A - fully closed B - fully open C - opened according to ambient conditions |
B - fully open |
|
The component(s) in a turbine engine that operate(s) at the highest temperatures is/are the A - first stage turbine nozzle guide vanes B - turbine disks C - exhaust cone |
A - first stage turbine nozzle guide vanes |
|
During an operational check of an electrically powered aircraft engine cowl flap system, the motor fails to operate. Which of the following is the fist to be checked? A - flap actuator motor circuit breaker B - flap actuator control switch C - flap actuator motor |
A - flap actuator motor circuit breaker |
|
(1) Some aircraft exhaust systems include an augmenter system to draw additional air over the engine for cooling. (2) Augmenter systems are used to create a low pressure area at the lower rear of the aircraft engine cowling. Regarding the above statements, A - only No. 1 is true B - both No. 1 and No. 2 are true C - only No. 2 is true |
B - both No. 1 and No. 2 are true |
|
Which of the following defects would likely cause a hot spot on a reciprocating engine cylinder? A - too much cooling fin area broken off B - a cracked cylinder baffle C - cowling air seal leakage |
A - too much cooling fin area broken off |
|
What part of an air-cooled cylinder assembly has the greatest fin area per square inch? A - cylinder barrel B - rear of the cylinder head C - exhaust valve port |
C - exhaust valve port |
|
Reciprocating engines used in helicopters are cooled by A - the downdraft from the main rotor B - a fan mounted on the engine C - blast tubes on either side of the engine mount |
B - a fan mounted on the engine |
|
The greatest portion of heat generated by combustion in a typical aircraft reciprocating engine is A - converted into useful power B - carried out with the exhaust gases C - dissipated through the cylinder walls and heads |
B - carried out with the exhaust gases |
|
A broken cooling fin on a cylinder head A - is cause for rejection of the head B - may be filed to smooth contours if damage and/or repair limits are not exceeded C - should be left alone |
B - may be filed to smooth contours if damage and/or repair limits are not exceeded |
|
An engine becomes overheated due to excessive taxiing or improper ground runup. Prior to shutdown, operation must continue until cylinders have cooled, by running engine at A - low RPM with oil dilution system activated B - idle RPM C - high RPM with mixture control in rich position |
B - idle RPM |
|
Cylinder head temperatures are measured by means of an indicator and a A - resistance bulb sensing device B - wheatstone bridge sensing device C - thermocouple sensing device |
C - thermocouple sensing device |
|
High cylinder head temperatures are likely to result from A - a very lean mixture at high power settings B - fouled spark plugs C - a very rich mixture at high power settings |
A - a very lean mixture at high power settings |
|
The purpose of an intercooler when used with a turbocharger is to cool the A - exhaust gases before they come in contact with the turbo drive B - turbocharger bearings C - air entering the carburetor from the turbocharger |
C - air entering the carburetor from the turbocharger |
|
Prolonged idling of an engine will usually result in A - excessive cylinder head temperatures B - increased oil consumption C - foreign material buildup on spark plugs |
C - foreign material buildup on spark plugs |
|
The most common method and generally the best conduction of heat from the inside of a cylinder barrel to the cooling air is accomplished by A - machining fins directly on the outside of the barrel B - shrinking on a jacket or muff of aluminum cooling fins around a steel cylinder sleeve C - machining fins directly on the outside of the barrel and shrinking on a jacket or muff of aluminum cooling fins around a steel cylinder sleeve (on different areas of the barrel). |
A - machining fins directly on the outside of the barrel |
|
What is the function of a blast tube as found on aircraft engines? A - a means of cooling the engine by utilizing the propeller backwash B - a tube used to load a cartridge starter C - a device to cool an engine accessory |
C - a device to cool an engine accessory |
|
Which statement is true regarding the air passing through the combustion section of a jet engine? A - most is used for engine cooling B - most is used to support combustion C - a small percentage is frequently bled off at this point to be used for air-conditioning and/or other pneumatic powered systems |
A - most is used for engine cooling |
|
Which of the following results in a decrease in volumetric efficiency A - cylinder head temperature too low B - part-throttle operation C - short intake pipes of large diameter |
B - part-throttle operation |
|
What is the position of the cowl flaps during engine starting and warmup operations under normal conditions? A - full open at all times B - full closed at all times C - open for starting, closed for warmup |
A - full open at all times |
|
Increased engine heat will cause volumetric efficiency to A - remain the same B - decrease C - increase |
B - decrease |