Ground Operation & Servicing

Question 0

How does one check for hydraulic lock?

Answer 0

Pull the propellor through three or four times in the direction of rotation.

Question 1

What is the proper way to extinguish an induction system fire that occurs when starting a reciprocating enging?

Answer 1

Keep the engine running (continue starting) and blow the fire out. If this does not work, use a CO2 fire extinguisher directed into the carburetor air inlet.

Question 2

What damage can result from hydraulic lock?

Answer 2

Bent or broken connecting rods.

Question 3

What information must be near oil fillers?

Answer 3

Oil type or reference to proper service manual.

Question 4

Why is it important that turbine fuel not be mixed with aviation gasoline that is used in an aircraft reciprocating engine?

Answer 4

The turbine fuel will cause the engine to detonate severely, resulting in engine damage or failure.

Question 5

Can AVGAS be used in a turbine engine?

Answer 5

Yes, for limited operations. Continued use could cause a loss in efficiency and damage.

Question 6

What damage is likely to occur if an aircraft reciprocating engine designed to use grade 100 fuel is operated with grade 80 fuel?

Answer 6

Overheating and detonation, damage including; bent connecting rods, burned pistons, and cracked cylinder heads.

Question 7

What are the physical and safety requirements needed for starting a power plant?

Answer 7

Checklist present, aircraft orientated into the wind, check blast are and intake area, secure GPU, and post a fire guard.

Question 8

What hand prop procedures should be followed?

Answer 8

Fuel switch on, magneto switch off, throttle closed, brakes on, contact.

Question 9

What kind of knot is used for securing an airplane with a rope?

Answer 9

Bowline.

Question 10

What brakes are used during towing?

Answer 10

The tow vehicles.

Question 11

Why should a mechanic know standard light signals?

Answer 11

For taxiing aircraft around active runways.

Question 12

Where are hand signals published?

Answer 12

Airman’s Information Manual (AIM), or ASA-AMT-G, General textbook, page 629.

Question 13

When fueling aircraft, what precautions should be taken?

Answer 13

Be sure to use the correct grade of fuel, ground the aircraft and fuel service vehicle, and protect the aircraft from damage from fuel hose and nozzle.

Question 14

When is pre-oiling of an engine needed?

Answer 14

New engines or preserved engines.

Question 15

What is a hot start?

Answer 15

On gas turbine engines, a start occurring with normal engine rotation, but EGT exceeds limits. Usually caused by an excessively rich mixture in the combustor. Fuel to the engine must be terminated immediately to prevent engine damage.

Question 16

Is automotive gas legal for use in aircraft engines?

Answer 16

Yes, only with STC (Supplemental Type Certificate).

Question 17

What are some indicators of water in fuel?

Answer 17

Hazy fuel, or visible slugs of water settled on the bottom of a fuel sample. Also, chemical additives can detect hidden water.

Question 18

What are some ground operation hazards?

Answer 18

FOD, other aircraft, people or obstacles, fire on startup, noise levels, propellors and rotor hydraulic lock, and limited visibility.

Question 19

What does the 100 in 100LL (low lead) AVGAS mean?

Answer 19

The fuels octane rating.

Question 24

When starting an aircraft engine that is equipped with a float type carburetor, in what position should the carburetor heat control be placed?

Answer 24

In the “Cold” position.

Question 25

How far ahead of an idling turbojet engine does the danger area extend?

Answer 25

25 feet.

Question 26

What grade of aviation gasoline is dyed blue?

Answer 26

Low-lead Grade-100 (100LL).

Question 27

What is meant by detonation in an aircraft reciprocating engine?

Answer 27

Detonation is an uncontrolled burning of the fuel in the cylinder of an engine. It is an explosion, rather than a smooth burning.

Question 28

What is the danger of using a fuel that vaporizes too readily?

Answer 28

Vapor lock can occur in the fuel lines, shutting off the flow of fuel to the engine.

Question 29

What type of fuel is Jet-A?

Answer 29

A fuel with a heavy kerosene base, a flash point of 110-150F, a freezing point of -40F, and a heat energy content of 18,600Btu/lb.

Question 30

What is the significance of the two numbers, 100/130, in the dual rating of aviation gasoline?

Answer 30

The first number is the octane rating or performance number of the fuel when operating with a lean mixture, and the last number is the octane rating or performance number when operating with a rich mixture.

Question 31

What are two functions of tetraethyl lead that is added to aviation gasoline?

Answer 31

It increases the critical pressure and temperature of the fuel, and it acts as a lubricant for the valves.

Question 32

What information must be located near the fuel tank filler opening in an aircraft powered by a reciprocating engine?

Answer 32

The word “Avgas,” and the minimum fuel grade.

Question 33

What information must be located near the fuel tank filler opening in an aircraft powered by a turbine engine?

Answer 33

The words “Jet Fuel,” the permissible fuel designations, or references to the Airplane Flight Manual (AFM) for permissible fuel designations. For pressure fueling systems, the maximum permissible fueling supply pressure and the maximum permissible defueling pressure.

Question 34

What action should a mechanic take while taxiing an aircraft on a runway if the tower shines a red flashing light at him?

Answer 34

Taxi the aircraft clear of the runway in use.

Question 35

What should be done to a reciprocating engine fuel system if turbine fuel is inadvertently put into the tanks and the engine is run?

Answer 35

The entire fuel system must be drained and flushed with gasoline, the engine given a compression check and all of the cylinders given a borescope inspection. The oil must be drained and all of the filters and strainers checked. After the aircraft is properly fueled, the engine must be given a proper run-up and check.

Question 36

Why is it important that the aircraft and the fuel truck be grounded together before the aircraft is fueled?

Answer 36

Grounding prevents the buildup of static electricity that causes sparks that could ignite fuel vapors.

Question 53

What type of fire extinguisher is best suited for extinguishing an induction fire in a reciprocating engine?

Answer 53

Carbon dioxide (CO2).

Question 54

What is the procedure if a hung start occurs when starting a turbojet engine?

Answer 54

Terminate the starting operation and find the reason the engine would not accelerate as it should.

Question 55

What is meant by a liquid lock in the cylinder of an aircraft engine, and how is one cleared?

Answer 55

Oil accumulates in the cylinders below the center line of the engine and prevents the piston moving to the top of its stroke. To clear a liquid lock, remove one of the spark plugs and turn the engine crankshaft until all of the oil is forced out of the cylinder.

Question 56

What special precautions should be taken when towing an aircraft that is equipped with a steerable nosewheel?

Answer 56

Be sure that the nosewheel does not try to turn past its stops. Some aircraft must have the torsion links on the nosewheel strut disconnected when they are being towed.

Question 57

What precaution must be observed regarding the tools used when servicing an aircraft oxygen system?

Answer 57

Be sure that there is no oil or grease on the tools. Pure oxygen can cause spontaneous combustion of petroleum products.

Question 58

What documentation is required for a certificated aircraft to legally operate on automotive gasoline?

Answer 58

There must be a Supplemental Type Certificate for the aircraft to operate on automotive gasoline.