Aviation Fuel Characteristics and Engine Performance

Using a lower grade fuel in an aircraft engine can lead to detonation, causing various issues such as loss of power, excessive heat, burned spark plugs, burned and sticky valves, and high oil consumption.

Detonation occurs when the fuel mixture ignites instantaneously rather than burning progressively and evenly, leading to a sudden rise in pressure within the engine cylinders. This can cause engine knocking, pinging, or even damage if not addressed promptly. The other options do not directly relate to the cause of detonation at high power settings.

Detonation in a reciprocating aircraft engine occurs when the unburned charge in the cylinder explodes instead of burning normally, leading to potential engine damage and inefficiency.

Pre-ignition occurs when the fuel/air mixture ignites before the spark plug fires, leading to potential engine damage. Detonation is an abnormal combustion where the fuel in the cylinder spontaneously explodes instead of burning smoothly. Backfire is the ignition of fuel in the intake or exhaust manifold instead of the combustion chamber. Carbonation is the process of adding carbon dioxide to a liquid to create carbonic acid.

When the recommended octane is not available, using a higher octane aviation gas is an acceptable substitute, although it is not the most desirable option.

Filling the fuel tanks after the last flight of the day is important to prevent moisture condensation by not leaving airspace in the tanks, which can lead to water accumulation and potential fuel contamination.

The correct answer refers to draining fuel from specific components directly related to the fuel system in an aircraft for water purging purposes.