PPL PPL Aircraft Systems and Powerplant 2

Question 1

What does manifold pressure (MAP) indicate in a piston aircraft?

Accepted Answer

The absolute pressure in the engine intake manifold, used to set power

Answer

Manifold pressure measures the absolute pressure of the air-fuel mixture in the intake manifold and is the primary power-setting indicator in many aircraft.

Question 2

What happens to a normally-aspirated engine's power output as altitude increases?

Accepted Answer

Power decreases because lower air density reduces the mass of air entering the engine

Answer

As altitude increases, air density decreases, so the engine ingests less air mass per stroke, reducing combustion energy and power output.

Question 3

What is the purpose of the mixture control in a piston aircraft?

Accepted Answer

To adjust the fuel-to-air ratio to maintain proper combustion as altitude and air density change

Answer

The mixture control adjusts the fuel-to-air ratio because air density decreases with altitude, requiring less fuel to maintain the correct stoichiometric ratio.

Question 4

What color arc on the tachometer indicates the normal continuous operating range?

Accepted Answer

Green arc

Answer

The green arc on the tachometer indicates the normal continuous operating RPM range approved by the manufacturer.

Question 5

What is the purpose of the alternator on a modern piston aircraft?

Accepted Answer

To continuously charge the battery and supply electrical power during flight

Answer

The alternator converts mechanical energy from the engine crankshaft into electrical energy to power avionics and continuously recharge the battery.

(PPL) Private Pilot Licence Practice Test

(PPL) Private Pilot Licence Practice Test

PPL PPL Aircraft Systems and Powerplant 2