Help: My airframe has become magnetic!!!!
Jan Lustrup
some welding to put in stonger enginestruts. Afterwards the compas is
crazy...The airframe in front og the compass is strongly "north"..
The compass shows 030 deg. no mater whitch way we fly....
Have tried using a AC coil to demagetize, but it dose not help.
Using DC with a small coil (to try to make "south pole" out of the area
that's "north") only makes things worse...
Anyone ideas?????
Jan Lustrup
HLAviation
>some welding to put in stonger enginestruts. Afterwards the compas is
>crazy...The airframe in front og the compass is strongly "north"..
Hmm interesting. What type of welder did you use, and was it set for AC or
DC if it was electric?
In most ports the US Navy uses, they have "Degausing Areas" to cure
problems like that on thier ships coming in and out. From what I understand of
it, which is very little, they just drive the ship through the area and some
force, magnetic I suppose, straightens or otherwise alters the magnetic fields.
Maybe the Airforce has something similar to realign the magnetic fields of
planes. Does anyone out there know? If they do then in light of good public
opinion in days of tightening budgets, they might let you use it.
Bob Gardner
Get a variable transformer capable of handling a lot of current. Take
anything that could be damaged by a magnetic field out of the airplane,
especially the compass. Wind the AC cord around the fuselage with no
current flowing, then ve-r-r-y slowly begin allowing current flow. When you
have max current flow for your variable device, leave it at that setting
for a short time and then begin reducing current flow back toward zero,
again very slowly. Should do the trick.
If you are anywhere near the coast, you should be able to get some advice
from compass adjusters in the maritime industry.
Bob Gardner
Jan Lustrup wrote:
> When changeing to a lager motor in my motorglider (SF25B) , I had to do
> some welding to put in stonger enginestruts. Afterwards the compas is
> crazy...The airframe in front og the compass is strongly "north"..
James Bieker
shielded devices before attempting to de-gauss (demagnetize) the airframe.
Most metal shops will remove the computers found in modern vehicles before
doing any welding, even on the frame. They discovered that it would cause
damage.
Mac
>
> snip
Not sure about demagnetising it. AIUI ships *used* to be de-gaussed with
a floating cable around the ship, and a VERY large AC current.
In the meantime it might be wise to avoid close-formation flying, you
might end up stuck together.
Sorry;)
--
Mac.
Richard L. Dillon
on the link, Compass Inaccurate. They rent a degausser for just the problem
you describe.
Hope this helps,
Richard Dillon
N600RD
HLAviation <hlavi...@aol.com> wrote in message
news:19990725142103...@ng-cd1.aol.com...
> >When changeing to a lager motor in my motorglider (SF25B) , I had to do
> >some welding to put in stonger enginestruts. Afterwards the compas is
> >crazy...The airframe in front og the compass is strongly "north"..
>
HLAviation
>on the link, Compass Inaccurate. They rent a degausser for just the problem
>you describe.
>
Hey thanks for the link. My planes OK but I'll keep that ref. At $75 it's a
deal.
Larry Fransson
In article <19990725142103...@ng-cd1.aol.com>, hlavi...@aol.com
wrote:
> In most ports the US Navy uses, they have "Degausing Areas" to cure
>problems like that on thier ships coming in and out. From what I understand
>of
>it, which is very little, they just drive the ship through the area and
>some
>force, magnetic I suppose, straightens or otherwise alters the magnetic
>fields.
That's about it. Does really screwy things to the TV picture when they do
that.
Larry Fransson
Seattle, WA
"Pilots are just plane people with a different air about them."
Dave Mould
degaussing coil. This is a large coil that is fed with AC. The coil is
placed around the affected area, after removing all magnetically sensitive
equipment from the aircraft (especially the compass - you don't want to
degauss that!). After the AC has been flowing for a few seconds, the
current through the coil is very slowly reduced to zero (or the coil can be
slowly moved away from the aircraft.)
The second way requires no special equipment, but is time consuming. The
aircraft must be flown East for 30 minutes, then West for 30 minutes, then
East again etc. for a few hours a day over a period of several days. I was
told about this method by an airforce pilot who had to fly this pattern
after a lighting strike. Apparently the Airforce has a hanger with a
degaussing coil, but it could not be booked for a month, and the East/West
flying was the alternative method. I've no idea if it would work, but the
Airforce guy seemed genuine.
Dave Mould
Jan Lustrup <lus...@online.no> wrote in message
news:379B4C...@online.no...
> When changeing to a lager motor in my motorglider (SF25B) , I had to do
> some welding to put in stonger enginestruts. Afterwards the compas is
> crazy...The airframe in front og the compass is strongly "north"..
HLAviation
>aircraft must be flown East for 30 minutes, then West for 30 minutes, then
>East again etc. for a few hours a day over a period of several days.
Imagine the fuel costs alone of that method, especially at the burn rates of an
airforce type plane. Good thing the taxpayer has deep pockets huh. I think
I'd rent the coil from Sacramento for $75.
Dave Mould
magnetic South pole, not a North pole. The North pole of a magnet is more
correctly termed the "North seeking pole", and will point to the South
seeking pole of another magnet. The Arctic (North Pole) is the Earth's
Southern magnetic pole (confusing huh?). So the airframe in front of the
compass sounds to me as if it is strongly "South", not "North".