Degaussing a Warrior

Maybe you should just give up and get a vertical card compass with a
remote sensor out in a wing tip.

Has anyone reading this group had to degauss a firewall? My Warrior
took a lightning strike last July while parked, melting a bit of the
propeller tip and magnetizing much of the plane forward of the firewall
(so that the compass always points towards the propeller). The engine
has now been overhauled, and all engine parts and the mount degaussed,
but after trying several compasses, we cannot get any to indicate
properly -- something is still strongly magnetized. Tomorrow my AME
(IA/A&P) will bring in a specialized meter and degaussing device to
start trying to hunt down the problem, but I'm quite discouraged being
grounded for this long.


Thanks in advance for any help,


David

Drew Dalgleish wrote:

Maybe you should just give up and get a vertical card compass with a
remote sensor out in a wing tip.

Using a remote sensor (probably in the tail rather than the wingtip) is
my fallback, if everything else fails. I'm not sure whether an STC
would be required for that.


All the best,


David

WIth the flux meter and a Color TV degausser coil, you should be able
to cure it... Even a compass will help you pick out the magnetized
areas in the engine compartment for giving the buzz treatment... The
key to using the degausser is to buzz the part and keep the power on
while you withdraw the coil, not put the coil against it and just turn
the power on and off...

denny

Denny wrote:
: WIth the flux meter and a Color TV degausser coil, you should be able
: to cure it... Even a compass will help you pick out the magnetized
: areas in the engine compartment for giving the buzz treatment... The
: key to using the degausser is to buzz the part and keep the power on
: while you withdraw the coil, not put the coil against it and just turn
: the power on and off...

I'll agree that the tv degausser will likely be able to do it. With all the
decorations (like engine mount + engine), it might be tricky to get in where you need
it to be.

I'd recommend removing any/all things possible to reduce the risk of
magnetizing anything else.

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Denny wrote:
: key to using the degausser is to buzz the part and keep the power on
: while you withdraw the coil, not put the coil against it and just turn
: the power on and off...

Oh, and if space constraints make it difficult or impossible to gracefully
move away while running, you can probably use a variac to ramp the field up/down to
simulate moving the coil. That's how the degaussers in monitors work.

-Cory

--

************************************************** ***********************
* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
************************************************** ***********************

Denny wrote:

WIth the flux meter and a Color TV degausser coil, you should be able
to cure it... Even a compass will help you pick out the magnetized
areas in the engine compartment for giving the buzz treatment... The
key to using the degausser is to buzz the part and keep the power on
while you withdraw the coil, not put the coil against it and just turn
the power on and off...

How about a tape eraser? Would be easier to get into tight places...

Yes, a bulk tape eraser will work.

"Darrel Toepfer" wrote in message
.. .
Denny wrote:

How about a tape eraser? Would be easier to get into tight places...

I strongly doubt a tape degausser will do you much good.
Likewise a color-TV coil.

You need a lot of field strength to clean [really, re-randomize..]
structual steel. You also need to be able to get that field where
it's needed.

Tapes and TV sets are orders of magnitude more subtle than the
results of a strike.

But feel free to try; just get the compasses well away before you
start.
--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

It doesn't matter how intense the strike was. The metal can only hold a
certain magnetic flux. If you exceed the metals maximum flux then the
degausser will work. The TV degausser was designed to degause iron and
steel, and so it can exceed the maximum magnetic flux of steel. It should
work fine. You can also use an AC motor as a degausser, and a small compass
as a field detector.

The Navy still has a number of degaussing stations in operation. If you can
just convince them to let you park your plane on the deck...

"David Lesher" wrote in message
...

I strongly doubt a tape degausser will do you much good.
Likewise a color-TV coil.

You need a lot of field strength to clean [really, re-randomize..]
structual steel. You also need to be able to get that field where
it's needed.

Tapes and TV sets are orders of magnitude more subtle than the
results of a strike.

But feel free to try; just get the compasses well away before you
start.
--
A host is a host from coast to
& no one will talk to a host that's close........[v].(301) 56-LINUX
Unless the host (that isn't close).........................pob 1433
is busy, hung or dead....................................20915-1433

Maybe you should just give up and get a vertical card compass with a
remote sensor out in a wing tip.

Both Canadian and American law require a nonstabilized magnetic
direction indicator that isn't dependent on the aircraft's electrical
system. The remote systems don't qualify. I wish they did, as the mag
compass can be a real pain to calibrate in any airplane that has
miscellaneous magnetic fields in it.

Dan