Strange compass behavior

Get a new flashlight? Mine had a big magnet in the bottom I didn't know
about. The flashlight now lives in my garage.

Thx, {|;-)

Victor J. (Jim) Osborne, Jr.



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Might have to move the compass up away from the panel. There are a lot
of electrics under the glareshield that could be interfering with it.
I had the same problem with a vertical card compass in an Ercoupe, and
had to put it way up on the windshield bow.
Those vertical card units are very sensitive to vibration. You HAVE
to use the really soft, floppy mount they provide for them.
Remember that GPS give you track, not heading, and if there's any
appreciable wind you won't get anywhere near accurate heading
indications for compass calibration purposes. Use the heading
indicator instead.

Dan

Dan Thomas wrote:

Remember that GPS give you track, not heading, and if there's any
appreciable wind you won't get anywhere near accurate heading
indications for compass calibration purposes. Use the heading
indicator instead.

Yep, forget the GPS. Use this method instead:

Line up on a taxiway or runway with a known, published heading and carefully set
the HI. Go fly on gyro headings 360, 030, 060, etc. and carefully record the
magnetic compass reading. You might want to try it with and without lights,
pitot heat, any other major power consumers. Return to your known taxiway or
runway and verify the HI hasn't drifted.

Dave
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There used to be an aricle on www.avionicswest.com (perhaps it's still there)
that talked about how the vertical compasses they tested were ruined by placing
a magnetic object a single time next to the compass. Things as innocent as
a Jepps binder (with it's steel spine). Sounds like they're great when they work,
but that you have to be very careful with them.
Max T, MCFI

Victor J. Osborne, Jr. wrote in message ...
Get a new flashlight? Mine had a big magnet in the bottom I didn't know
about. The flashlight now lives in my garage.

Thx, {|;-)

Victor J. (Jim) Osborne, Jr.



take off my shoes to reply

Wonderful article, it is still there, thanks for the tip. The URL is:

http://www.avionicswest.com/articles.htm#MAGNETIC%20COMPASS!

That might explain exactly what we're seeing!

--Michael A.

"Max T, CFI" wrote in message
news:mjfXb.311421$na.464770@attbi_s04...
There used to be an aricle on www.avionicswest.com (perhaps it's still
there)
that talked about how the vertical compasses they tested were ruined by
placing
a magnetic object a single time next to the compass. Things as innocent
as
a Jepps binder (with it's steel spine). Sounds like they're great when
they work,
but that you have to be very careful with them.
Max T, MCFI

Victor J. Osborne, Jr. wrote in message
...
Get a new flashlight? Mine had a big magnet in the bottom I didn't know
about. The flashlight now lives in my garage.

Thx, {|;-)

Victor J. (Jim) Osborne, Jr.



take off my shoes to reply