What is the distributor in an aircraft ignition system?

• A. Sends the spark to the correct cylinder via a rotating finger and points.
• B. Regulates fuel flow to each cylinder.
• C. Measures engine oil pressure for timing.
• D. Controls throttle position.

Answer: (A)

Distributors in aircraft ignition systems are responsible for routing the high-voltage spark from the ignition coil to the correct cylinder at the right moment. The distributor uses a rotor (the rotating finger) that spins inside the distributor cap and makes contact with each spark plug wire in the correct sequence as the engine rotates. This arrangement ensures the spark occurs in the proper cylinder and at the proper timing, which is essential for smooth engine operation and efficient combustion.

The other functions listed aren’t what the distributor does: regulating fuel flow is handled by the fuel metering system, measuring oil pressure is related to lubrication and engine monitoring rather than ignition timing, and throttling controls air intake rather than spark distribution.