What is the name for the pin attaching the piston to the connecting rod in a piston engine?
select one
a. journal pin
b. gudgeon pin
c. tie pin
d. elbow pin
b. gudgeon pin
In a four stroke engine, when the piston is at BDC at the end of the inlet stroke the position of the valves is:
select one
a. inlet open, exhaust open
b. inlet open, exhaust closed
c. inlet closed, exhaust open
d. inlet closed, exhaust closed
b. inlet open, exhaust closed
What is the purpose of the slowest rotating shaft in the engine?
select one
a. to open the valves and it runs at half engine speed.
b. closes the valves and runs at engine speed.
c. closes the valves and runs at half engine speed.
d. to open the valves and it runs at engine speed.
a. to open the valves and it runs at half engine speed.
What is torque?
select one
a. force/distance
b. force applied directly to the end of a rotating shaft
c. pressure/area
d. force applied at a distance from the centre of a rotating shaft. force x distance
d. force applied at a distance from the centre of a rotating shaft. force x distance
The valves are closed by?
select one
a. recuperating cam action
b. the cam moving out of the way allowing the pressure to close the valves.
c. the crankshaft rotating far enough to allow closure by the half shaft.
d. the cam moving out of the way allowing the spring to move the valve.
d. the cam moving out of the way allowing the spring to move the valve.
Which component does a petrol engine need that a diesel engine doesn’t?
select one
a. magneto
b. exhaust valve
c. glow plug
d. inlet valve
a. magneto
If you had a 6 cylinder in-line petrol engine and you wanted a shorter engine with the same number of cylinders, what would be the best design option while trying to keep drag to a minimum.
select one
a. transverse
b. vee
c. inverted
d. radial
b. vee
What are the main differences between a petrol and a diesel engine?
select one
a. petrol engines have a lower power to weight ratio and are stronger
b. diesels have a higher compression ratio and no spark plugs
c. diesel engines do not need help with combustion during starting.
d. diesels have a lower compression ratio and no spark plugs or magneto.
b. diesels have a higher compression ratio and no spark plugs
Which of the following statements is true?
select one
a. AVGAS 100 is green and AVGAS 100LL is blue and they have different anti-detonation capabilities.
b. AVGAS100LL is blue with an SG of 0.8
c. JET-A1 is straw coloured to clean with a SG of 0.7
d. AVGAS 100 is green and AVGAS 100LL is blue and they detonate under the same conditions.
d. AVGAS 100 is green and AVGAS 100LL is blue and they detonate under the same conditions.
What might you have done which is likely to cause detonation?
select one
a. you put in too high in octane fuel
b. set climb thrust while in straight and level flight
c. reduced the RPM before reducing the power (MAP)
d. increased the RPM to max before setting take off power
c. reduced the RPM before reducing the power (MAP)
The engine is losing power and running intermittently rough, you have carried out checks for possible detonation, which has not helped. If the cause isn’t detonation, what other combustion-related problem could it be?
select one
a. acceleration pump not working
b. pre-ignition
c. one of the valves is opening before it’s stroke starts
d. mixture stuck at take off setting
b. pre-ignition
There average fuel density or specific gravity for JET A1 is approximately:
select one
a. 0.795
b. 0.695
c. 0.6
d. 0.95
a. 0.795
What is a vapour lock?
select one
a. a method of shutting down the engine and further preventing restarting
b. when the main jet is prevented from vaporising fuel
c. when a bubble of fuel vapour forms in the fuel lines preventing fuel flowing
d. when a bubble of vapour forms in the inlet manifold just before the inlet valves
c. when a bubble of fuel vapour forms in the fuel lines preventing fuel flowing
When increasing power by operating the throttle, which component in the carburettor prevents the mixture from changing?
select one
a. the diffuser without which the mixture would lean off
b. the diffuser without which the mixture would richen
c. the pressure balance duct
d. the power enrichment system
b. the diffuser without which the mixture would richen
Which carburettor component prevents flat spots?
select one
a. idle cut off
b. power enrichment
c. acceleration pump
d. mixture control
c. acceleration pump
The commonest reason for a carburettor fire during start is over-primming. What action should be taken if the engine has already started?
select one
a. continue cranking and priming unit the engine stops
b. run for awhile and if the flames stop you are clear to continue.
c. immediately evacuate the aircraft
d. run it for a minute before shutting down and then inspecting the engine
d. run it for a minute before shutting down and then inspecting the engine
The most likely conditions to encounter carb icing are?
Select one
a.temperature of -5°C to +18°C with high humidity
b.temperatures below -20°C
c.temperatures of +5°C to -18°C with high humidity
d.any temperatures with cloudy skies
a.temperature of -5°C to +18°C with high humidity
On selecting carb heat, what might you expect if there is carb icing in your carburettor?
Select one
a. the engine would lose power and stay at that level
b. the engine would immediately recover
c. the the engine would run rough then power would drop off before stabilising
d. the engine would run rough before could recovering and picking up power
d. the engine would run rough before could recovering and picking up power
The engine temperature gauge on your aircraft has a green range from 350°F to 450°F. What type of engine cooling system do you have?
select one
a. air cooling
b. oil cooling
c. liquid cooling
d. hybrid cooling
a. air cooling
When starting a piston engine in cold weather, the oil pressure can become excessively high initially, why?
select one
a. Because the viscosity of cold oil is low and this is okay providing it returns to normal as the engine warms up
b. because the viscosity of cold oil is high and this is okay providing it returns to normal as the engine warms up
c. because the viscosity of cold oil is high and this is okay providing it stays at the same pressure as the engine warms up
d. because the viscosity of cold oil is low and this is okay as long as you are using Fully Synthetic Multi-Grade oil
b. because the viscosity of cold oil is high and this is okay providing it returns to normal as the engine warms up
What must you be aware of when selecting oil for your aircraft especially when not at your home air base?
select one
a. there are two numbering systems and it is always important to select the lower one.
b. there are two numbering systems for oil viscosity and getting the wrong one could lead to engine failure.
c. there are two numbering systems and it is always important to select the higher one.
d. there are two numbering systems Saybolt and SAE. They are the same, except at the lower numbers.
b. there are two numbering systems for oil viscosity and getting the wrong one could lead to engine failure.
Which of these statements is true when the Magneto is OFF?
select one
a. the primary winding circuit is broken by the switch
b. there is a circuit through the switch to ground
c. the grounding circuit to the primary is broken.
d. the secondary winding circuit is broken by the switch
b. there is a circuit through the switch to ground
Apart from redundancy, why are two spark plugs fitted to each cylinder?
select one
a. it saves wear caused by using just one magneto constantly.
b. it reduces the time for complete combustion and improves efficiency.
c. it reduces the time for complete combustion and provides more voltage
d. it requires less fuel.
b. it reduces the time for complete combustion and improves efficiency.
Name the two things a spark augmentation systems need to give us for good engine starting.
select one
a. high secondary current and retardation
b. high primary current and advancement
c. high primary voltage and advancement
d. high secondary voltage and retardation
d. high secondary voltage and retardation
