Standby compass

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I recently work with the new Cessna 408. If you don’t know what it is, it is a new production, which means new certification aircraft.

The interesting thing is the aircraft is certified without a standby compass. It has the battery backup in the event of total electrical failure and therefore no whiskey compass.

Now, if you install all the fancy EFIS and have a standby system on an experimental, such as as a G5 or GRT mini, for example with a battery backup, would you need to have a compass?

The way I read the reg, if you have an electronic instrument with magnetometer and battery backup, the compass is not required.

 

[Sam Buchanan]

The way I read the reg, if you have an electronic instrument with magnetometer and battery backup, the compass is not required.

That is the common interpretation in the RV community and seems to be acceptable to DARs.

However, if a whiskey compass is installed it must have a correction card.

 

[lr172]

The regs now say magnetic heading indicator and not compas. Batt backup not required by regs. So the average person would say, yes this is adequate. However, if you use the fsdo some of these guys have their own interpretation of the regs. First guy said magnetic heading indicator means compass. I explained that compass is just one form of indicator. He says No compass, no a/w cert. second guy said where is your compass . I pulled up the regs and he says, oh, didn’t know that, all good.

 

[MacCool]

I pulled the whiskey compass from my glareshield a couple of years ago after reading a discussion about it here on VAF. It was dead weight.

 

[Ironflight]

For Day VFR flight in your E-AB, you don’t need ANY instrumentation - so no compass is required. For night VFR or IFR operations, you’ll need the equipment specified in 91.205 - and the requirement is for a “magnetic direction indicator” - EFIS satisfies this, and no backup is required.