RE: REFLECTOR: SNF & Panel

["Chuck Caldarale" <n828cl@ix.netcom.com>]

> From: owner-reflector@awpi.com [mailto:owner-reflector@awpi.com]On
> Behalf Of Matt Harrop
> Subject: Re: REFLECTOR: SNF & Panel
>
> Many people have mentioned standby vacuum as essential for IFR operation.
> While I agree with the reasoning, I think the conclusion is somewhat
> flawed.  Since the fact is that if you lose your AI in IMC you will
> probably die, I plan to install an electric AI as a backup to the vacuum
> driven instruments.  Having a vacuum gyro and an electric gyro
> means that a single failure can't take them both out.

If you practice partial panel IFR, you shouldn't die due to loss of the AI.
Unfortunately, most of us don't take the time to do so.

The electric AI is horribly expensive, and doesn't really address the
primary failure mode of sudden vacuum pump failure. Since gyros rarely fail
(and usually give plenty of warning when they do), it seems odd to use
another gyro to get around the vacuum pump problem. At $350, the Precise
Flight SVS seems to be incredibly cheap IMC insurance.

I'll put the money saved over an electric gyro (~ $1000) towards a
Strikefinder (almost a necessity in the midwest).

 - Chuck