Pfly
Well-Known Member
It's perfectly safe for the airplane.
We did a crossfeed check every runup on the PA-44s at my university. Turn them both off, wait for fuel pressure to drop, turn them to crossfeed make sure it rises, turn them back to off make sure it drops, turn them both to ON make sure it rises. Our chief pilot killed the engine with the fuel selector on my CMEL ride.
I was told the "never touch the fuel selectors" rule (and the "no passengers" rule) at ATP was done after the fatal accident near RDU where both crossfeeds were found selected in the off position. It's a pilot problem, not dangerous to the aircraft. Although since in theory the fuel selectors on ATP's seminoles shouldn't have moved in years, I personally never moved them when I was a CFI there for fear they would get stuck or something.
The point is, the airplane belongs to someone else, someone who signs your paycheck, and you live by his rules or move on. Just that simple.