Would any of the knowledgeable EuroGA people out there know if this sort of unit would sniff out AvGas? On the scroll down list of photos it mentions being able to detect “Gasoline” but I’m slightly suspicious. Does anybody out there know how these units detect flammable gasses and if AvGas/ Gasoline/Petrol is something this unit could detect?
The page you are referring to explicitly says it can detect gasoline, gasoil (and by inference, jet fuel) and other hydrocarbons. How it works – good question. My educated guess is it may be measuring a specific peak in the infrared absorption spectrum. The wavelength of this peak is almost the same for the vast majority of acyclical hydrocarbons. A single-wavelength sensor is trivial to design (using e.g. an interference filter to select the proper wavelength).
How good it is at sensing, you’ll probably have to track down the manufacturer and ask for a factory test report.
Thanks @Ultranomad. My rubber hoses (on the overflows/vents) were replaced during the recent respray. There is no leak from the fuel tank selector or primer. All other pipes are metal. There is no smell in the wings or signs of fuel leaks from the tanks. It’s nothing major but I’d like to track the (occasional) smell down
Also thanks to @Peter always working in the background/ tidying up posts and changing my link to something much tidier .
@Archer-181, I don’t think this instrument will be of much help in finding a leak, as the fuel vapour will diffuse pretty fast. I would first try a low-tech solution, like wrapping the suspect location in paper coated with gasoline-soluble paint. Seeping or dripping will leave a trace on the paper.
My view would be that fuel leaks should not be happening and if they are then either something is split/damaged or somebody worked on the plane who should not be working in a lawn mower shop.
I had a leak on a fitting on a fuel totaliser
and it was just a scratch on the tapered mating surface, which prevented a total seal. You would not see that scratch unless you looked for it. This is not acceptable, but is fairly obvious when you pressurise the system with the elctric fuel pump, with the top end of the pipe (feeding the fuel distributor) blocked off.
The scratch was on where is says “no sealant here” here.
If this 22 quid thing worked, it would be great
BTW with ebay and amazon the only bit of the URL that’s needed is only up to the item reference. The rest is just garbage and might contain your site ID or even your password.
Avgas has a very useful blue dye in it and these usual show the leaks without any need for gas detection equipment any more sophisticated than the MK 1 human nose.
The most difficult leaks to find are those from porous aluminium tubes, even the smallest of these can be detected by the pipe being colder than the surrounding structure due to the Avgas evaporating.
Thanks to all – No marks from the blue dye but I have been using the Mk 1 human nose today and I’m getting closer!
I ordered the Ebay device and I’ll report back in due course. Thanks for the hints and tips.
Amazingly the Ebay detector works really well. It has narrowed down the position of the leak. You can set the sensitivity so with no vapour it clicks like a Geiger counter. As the vapour level increases, the tone rises.
Tomorrow I need to take off an inspection panel so get to the critical area and I’ll report back some more.
Any technical details on how it works?
