how are OPERATING HOURS defined?
How does Rotax measure "Operating Hours"?
I know some people with Pipers and Cessnas... usually measured their flight hours using the HOBBS reading to maximize the hours they can log, while maintenance actions were based on Tach hours, which are typically less than the Hobbs hours for the same flight, so that they can stretch out periodic maintenance, and delay the expenses.
On my aircraft, with a Dynon SkyView display showing values for my Rotax 912iS Sport engine, there are actually 3 values presented:
Hobbs
Tach
Engine
Which of these three varieties of hours does ROTAX consider to represent "Operating Hours"?