Maintenace Cycles How?

[balaton]

Hi All,

May be a stupid question, but what is considered from an engineering point of view when determining maintenance cycles, checks, etc. The block-to block time or the flight time (takeoff-landing). A/C logbooks contain both. Why?

Thanks,

b

[john_tullamarine]

Matters such as cycles will be defined by the OEM and, on occasion, such definitions don't seem to be all that logical but, there you are.

Hours related matters usually are airtime only ie wheels off to wheels on.

[HAWK21M]

Out here for maintenance calculations Cycles and Flt hrs are considered.
1 Takeoff and landing is one flight cycle and airborne to touchdown is flt hrs or time in air.