tmyers
En-Route
At what rpm is does a tach hour meter record 1 to 1?
Did they teach that technical terminology in A&P school Duncan?
When the engine is not running and the keys are in your pocket.
I haven't done a careful check (there is an offset because the tach was replaced) but they should be pretty close. There will be small differences because the hobbs runs off the key and the tach starts counting when the engine starts. The hobbs used to run right off the master so it would tick away when the master was on for things like a transponder check.So your Hobbs and tach always read the same?
At what rpm is does a tach hour meter record 1 to 1?
the hobbs runs off the key and the tach starts counting when the engine starts. The hobbs used to run right off the master so it would tick away when the master was on for things like a transponder check.
AFaIK, all mechanical tachs (including electric tachs that run from a tach generator) accumulate time at a rate proportional to RPM (e.g. twice as fast at 2000 RPM vs 1000 RPM) and all have a specific RPM where "tach time" runs like a Swiss watch (i.e. 1hr on the tach takes one our of "real" time. That RPM varies on different airplane models and if the RPM reading is in error, the "clock time" indicated RPM will be off as well (the time is proportional to actual engine RPM not indicated RPM).Your tach runs at "normal speed" continuously when the engine is running? My experience is that they are proportional to power. Certainly if I spent two hours on the hobbs doing pattern work (especially full stop landings) I'd expect to see far less than two hours on the tach time.
Your tach runs at "normal speed" continuously when the engine is running? My experience is that they are proportional to power. Certainly if I spent two hours on the hobbs doing pattern work (especially full stop landings) I'd expect to see far less than two hours on the tach time.
Cattywampus is a tried and true technical term. Wonky just doesn't sound right.
My normal cruise is 24 square and redline is 2700. My Hobbs runs off of oil pressure, wonder if the switch is not staying engaged.