Roy Smith wrote:
"Guillermo" wrote:

Perhaps... but what if you're in IMC and partial panel?


My initial thought was "one emergency at a time, please". If you're
partial panel in IMC and you then lose the engine, you're goose is probably
cooked anyway.

But, then I realized that any engine failure (in a typical 6-pack equipped
piston single) is going to involve loss of vacuum, so you're going to be
partial panel anyway.

Why? I believe most vacuum pumps are mechanically driven from the
engine so as long as the engine is turning, there should be vacuum. If
the failure is due to fuel or spark, then I don't see a vacuum loss.
Likewise, a "light" mechanical failure (valve, rocker arm, etc.), that
doesn't impede crank rotation also shouldn't cause vacuum loss. Now, if
you break the crank, throw a rod, or lose oil, then I can see the
likelihood, or even certainty, of the engine rotation ceasing and the
vacuum pump ceasing with it.

I'mnot suggesting that you shouldn't practice power off instrument
approaches though!

Matt