Snowbird wrote:

I could be mistaken, but I don't believe windmilling will
produce sufficient vacuum to keep the gyros spinning reliably.

FWIW, my engine at idle won't keep the vacuum gauge in the green, but the AI
and DG appear to work properly. Would a windmilling prop produce as much as
1,000 rpm?

George Patterson
Some people think they hear a call to the priesthood when what they really
hear is a tiny voice whispering "It's indoor work with no heavy lifting".