Is there a legal definition of a "cycle" on a jet engine?
We must log the cycles, and some maintenance is determined by cycles. From my understanding, this is partially because of the thermal dynamics of an engine cooling and then reheating, and partially because full takeoff power is used.
The "usual" time that you log a cycle is when an engine is started and the aircraft then takes off (using full rated takeoff power), but what about unusual situations like:
- Engine shutdown and restarted in flight
- Engine started, aircraft takes off, and then returns for a low pass or a touch and go: Would this be two cycles (does it depend on the amount of power used during the touch and go?)?
- Engine started and then shut down without a flight