Compass Install

[Dorsal]

JF, in Canada you have to have a compass or a magnetic direction indicator that is independent of your electrical system.

I stand corrected, anyone know if the "independent of your electrical system" holds true in the US? and does battery backup make it independent of your electrical system given it will read on its own?

[Esser]

Good read about degaussing: http://www.sacskyranch.com/degaussi.htm

[chefwarthog]

Dorsal, This is wath i had in mind, a battery backup SkyView vs compass.... I know that in Canada the legislation is in some points, diverge from our neighbor.

What, you know about that Esser?

[jtpitkin06]

Dorsal, This is wath i had in mind, a battery backup SkyView vs compass.... I know that in Canada the legislation is in some points, diverge from our neighbor.

Actually, Canada reg reads

605.14 No person shall conduct a take-off in a power-driven aircraft for the purpose of day VFR flight unless it is equipped with

<snip>

(d) a magnetic compass or a magnetic direction indicator that operates independently of the aircraft electrical generating system;

The "generating system" is your possible loophole whereas an emergency battery is not a generator. Check with your inspector or with TC to be sure. Be aware that if you fly it to the US you could get grounded until a compass is installed.

In the US, I think you will find the regs say a magnetic compass (not electronic) is required for basic VFR. There may be an exception somewhere but my local EAA tech counselor says no. Unless you know of an exemption and have confirmed it with your DAR you should plan on a wet compass.

Even in the B-767 with 5 electrical sources, 3 inertial reference systems, 2 GPS’s, dual slaved RDMI’s, dual FMC’s, and 3 air data computers, the lowly whiskey compass is still required.

For a head spinning, “How did they get away with that?”… Next time you fly commercial in an MD-80, stop by the cockpit and ask to see the whiskey compass. It’s behind the F/O’s right shoulder on the ceiling. To view it, each pilot has a folding mirror on the glare shield and there is a fixed mirror on the cockpit bulkhead. Yep… the cheesy mirrors and the compass light are required. I couldn’t make this stuff up.

John

[Dorsal]

Hmmm interesting thread, I read magnetic as uses the earths magnetic field for reference which I thought both a whisky compass and a magnetometer do. I will hav to review the regs regards electric but my DAR did not raise it as an issue.

[MotReklaw]

Guy I know got a compass from walmart and fastened it to his glareshield and did his own compass error chart and fastened it to the glareshield.
Passed the DAR.

[Dorsal]

It appears that the FAA changed the language from non-stabilized magnetic compass to magnetic direction indicator. This is as of AC23.1311-1c section 8.8.1, if I read this right the change was made to allow for "magnetically stabilized direction indicators (or electric compass systems)". I suspect John is correct that the best bet is to check with your DAR.

[chefwarthog]

That's what I will do!!!. because the compass it's juste an another backup.... and if the skywiew is battery backup, and dual ADAHRS, there is no need for a third backup system...... it's not a airliner that we fly..... for a third backup the Ipad or a hand-held GPS is much better then a compass that goes spining every time you touch the stick.....

[Jfquebec]

JF, in Canada you have to have a compass or a magnetic direction indicator that is independent of your electrical system.

I have compass....

[jtpitkin06]

Well, I stepped on it this time… someone needs to smack me on the side of the head and yell in my ear, “It’s experimental, dummy!”
This is one of those FAA /Canadian goose chases. The AC 23.1311 is largely for certified aircraft. It refers the reader to part 23 for equipment requirements where it is very specific about non-stabilized magnetic compass. But this is for certified airplanes in the US. We know that for experimental in the US, just about anything goes. Yes, you can use a Wal-mart compass. Just as you can use an Autozone oil pressure gauge.

Sec. 23.1303

Flight and navigation instruments.

The following are required flight and navigational instruments:
(a) An airspeed indicator.
(b) An altimeter.
(c) A direction indicator [nonstabilized magnetic compass.]

But again, that is for certified. In the US experimentals fall largely under the “run whatcha brung” regulations. So if you are flying experimental DAY VFR in the US you don’t need any instruments at all. Nada… Zip… When you add night or IFR flying, then the instruments required rule kicks in.

Canada is a whole different set of rules. Some more restrictive and some more sensible. TC realizes a magnetic compass gets pretty useless north of Yellow Knife or Iqaluit. At the same time, the FAA is making progress to allow new technology in certified aircraft. So for the experimental airplanes, no matter what country, just check with the inspectors and see what they want for your operation; be it DAY or NIGHT. If they say it’s OK to go with the battery powered electronic I see no reason not to go with it.

Sorry if I misled anyone with the anecdotal ramblings.

John