2.16: Abnormal Combustion

Question 1

Detonation occurs in a reciprocating aircraft engine when

Answer 1

the unburned charge in the cylinders explodes instead of burning normally.

Question 2

Detonation may occur at high-power settings when

Answer 2

the fuel mixture ignites instantaneously instead of burning progressively and evenly.

Question 3

If a pilot suspects that the engine (with a fixed-pitch propeller) is detonating during climb-out after take-off, the initial corrective action to take would be to

Answer 3

lower the nose slightly to increase airspeed.

Question 4

If the grade of fuel used in an aircraft engine is lower than specified for the engine, it will most likely cause

Answer 4

detonation

Question 5

The uncontrolled firing of the fuel/air charge in advance of normal spark ignition is known as

Answer 5

pre-ignition