Compass Fluid??

[PW Cooper]

Anyone know what sort of fluid is used in a magnetic compass these days and where I can get some?
Thanks
Coops.

[shortstripper]

Pure Alcohol! :\ .... Chemist?

SS

[porridge]

Had one leak on me recently, touched the fluid and smelt it. Felt and smelt like white spirit. Pehaps it was, but bet it was marketed and sold as: Aviation compass fluid - £175 per 10 cl!

[ShyTorque]

Is this an analogue compass or a digital one?

If it's analogue, it'll be seal oil, for the oil seal.

Or, if you want to make it really accurate, use correction fluid.

[VP959]

Varies. It always used to be denatured alcohol (easily detectable by the smell) in older ones. Newer compasses seem to use either white kerosene (central heating fuel oil works well) or thin silicone fluid.

One thing I learned whilst trying to refill one years ago was that it is extremely important to know EXACTLY which fluid was used in that particular make and model of compass. I used kerosene in one designed to take denatured alcohol once, and watched in horror as the numbers floated off the dial...................

VP

[Mark 1]

LAS do compass overhaul kits including fluid - about £30 IIRC
www.lasaero.com/

[DubTrub]

Johnson's baby oil. £1.95 at Boots.

Don't laugh, it works.

[AerBabe]

And if it doesn't, break the compass to get the oil back out and you'll forget you even cared!

[Ni Thomas]

Use Gin ..... preferrably Gordons
Two benefits:-
1) Gets rid of air bubbles.
2) Aids fortification whilst you await rescue :\

[egbt]

By complete coincidence earlier today I picked up this Chirp report from 1999 whilst searching for something else.

You have been warned!


Pilot Incapacitation

Reported occurrences of pilot incapacitation in General Aviation are relatively rare, but that does not mean that the problem does not exist. Incapacitation can result from several causes and may have extremely serious consequences in a single-pilot operation, particularly if the problem is not recognised at an early stage. The following report describes the insidious nature of some forms of contamination and the benefit in taking prompt action.

I collected our group PA32 from the Midlands on a Spring morning in 1994 for a day trip, with my wife and small children, to visit relations near the South Coast. On checking the aircraft I examined the 'snag' sheet, which was used to detail any known faults/comments noted by previous pilots and still outstanding. A 'snag' had been noted that stated that the compass fluid was leaking. Inspection of the compass (top centre on the windscreen) showed a small bubble at the top. Conditions were good VMC, the VORs all worked correctly, I was familiar with the route and I also carried a small hand compass in my flight bag. I could check the Direction Indicator against the runway heading prior to departure and with the aid of VORs in flight, so I was quite happy to go ahead.

On climb out I did notice that a prolonged trickle of fluid ran from the compass onto the carpet just in front, and between, the pilot and front passenger seat. I thought nothing more of it. After about 20 minutes my wife complained of feeling sick - very unusual, as she has never experienced airsickness. However, it was a little bumpy so, again, I was not unduly concerned - although I did register the fact that the compass fluid did produce quite a strong smell. A few minutes later she was clearly in some discomfort, shortly followed by a complaint that she was losing the feeling in her legs. She does suffer from mild asthma and it then struck me that she could be suffering from the affect of the smell of the fluid leaking from the compass. I felt fine but, as a precaution, I immediately adjusted all the available fresh air direct to my face. I then diverted to the nearest available airfield and executed what I thought to be a perfect landing just 10 minutes later - only to be told as I turned off the grass runway that I had landed "off the runway". I had, in fact, not noticed that the runway markers had recently been moved and, instead of landing between the markers, I had landed on the nicely cut strip to the right of the right side markers. I still felt fine - although slightly embarrassed!

On explaining my predicament as I taxied to park the aircraft, the airfield could not have been more helpful, instructing me to immediately shut down. They entertained my children, provided first aid for my wife who rapidly recovered in the fresh air, and removed the compass, which we carried home in the external locker - all without charge or landing fee! After an hour or so we completed our journey.

It may be just as well that my wife's asthma probably caused her to be more sensitive to the smell giving me advance warning of the problem - the prospect of heading west on autopilot whilst slowly losing one's judgement does not bear thinking about! I certainly do not recall any aspect of my training (including commercial balloon pilot exams.) that warned of the dangers of noxious fumes from a leaking compass!