"J.Kahn" wrote in message
.. .

For powerplanes, it would be prudent to go to a safe altitude and practice
180s upon chopping power and noting the altitude loss with optimum
technique (although it's murder on the poor cylinders, best to use a
renter...). The least loss is with a hard 45 deg banked turn. If with
some practice you can confidently complete a 180 with say a 400 ft
altitude loss you can set a defined go-nogo limit of say 500 ft for
turnbacks and you've removed the guesswork from it.

I dont know. doing this at altitude makes the manuver safe, and learning to
perfect it that way can give the pilot overconfidence.

best to make sure your'e never in the situation that call for such a
manuver, and take the taime to make sur the plane works rather than building
confidence that you can do what others haven't