d&tm wrote:

in my PPL training it was drummed in to me the importance of always doing
the w & b calcs with the fuel you were taking and also the zero fuel case.
I posted sometime ago that with the Warriors I flew it was impossible to go
outside the w & b envelope by burning fuel. I have just finished my
transition to the C172 and have extensively investigated different loading
scenarios and found exactly the same thing, at least with this N model I am
flying.
Are there any single engine airplanes out there that really can go outside
the envelope by burning fuel? ( I am only interested in the normal
ategory - not utility). Perhaps the training is just to prepare you for
heavy aircraft?
Terry


Bonanza's come immediately to mind.
I do not know if the current models are built this way, the older models
had the fuel stored in the front of the wing, ahead of the main spar.
Any weight in the aircraft behind the front seats is behind the fuel
weight. As fuel is burned, the weight ahead of the spars decreases while
the weight behind the spar remains the same, hence the cg moves aft. At
some point, the cg moves out of the envelope (the ability of the
horizontal stabilizer to provide sufficient lift).
Piper PA32's will can also develope this situation.
Cessna's seem to have a broader range.
You have to look at each aircrafts envelope.

Van's tandem seat RV-4's had a bad string of fatal accidents until the
word got out and builders became more aware of the potential danger.