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Hey guys, Just wondering how everyone is verifying fuel levels in their tanks. I was always taught to never trust a fuel gauge in an airplane. Just curious if most people just top off before each flight and go off of fuel burn figures or has anyone made a way to stick the tank to check fuel level. We made a test stick that seems like it will work but haven't calibrated it yet. Thanks, Jake

I have sharpie lines on the back side of the tank in 2 gallon increments. One set for the 3 point stance and once for level flight. A peak under the panel makes seeing the ammount of fuel a piece of cake during the preflight. A fuel flow meter monitors how much is being used in flight. If I doubt the meter I can verify by peeking back under the panel but it’s not as easy when strapped in. Others have used the plans version of a clear sight tube. It’s simple and failsafe and maybe the way I’d go if doing it again.

Keith
#554

I have the fuel flow meter and fuel gauge. Didnt go with the sight tube. I have a second panel below the standard panel that wont allow easy sight of the fuel tank. Im hoping for first flights in a few months!!

I am going with a backlit, marked tank and a cheap backup camera. Jeff has a YouTube video showing his setup.

https://youtu.be/pnXE_hSvlJI

kmacht wrote:I have sharpie lines on the back side of the tank in 2 gallon increments. One set for the 3 point stance and once for level flight. A peak under the panel makes seeing the ammount of fuel a piece of cake during the preflight. A fuel flow meter monitors how much is being used in flight. If I doubt the meter I can verify by peeking back under the panel but it’s not as easy when strapped in. Others have used the plans version of a clear sight tube. It’s simple and failsafe and maybe the way I’d go if doing it again.

What you describe is exactly my plan except I have the Princeton fuel probe running to an MGL Flight-2 that is quite accurate. Even when I mix a bit of Mogas with my 100LL the reading is pretty accurate. Of course you can always use this method (note the panel slot):



FWIW,

Dale Williams
N319WF @ 6J2
Myunn - "daughter of Cleanex"
120 HP - 3.0 Corvair
Tail Wheel - Center Stick
Signature Finish 2200 Paint Job
171.9 hours / Status - Flying
Member # 109 - Florida Sonex Association
Latest video: https://www.youtube.com/watch?v=1VP7UYEqQ-g

Hi:

The sight gauge is just about foolproof.

http://www.mykitlog.com/users/display_l ... 2339&row=1
http://www.mykitlog.com/users/display_l ... 2340&row=2

I also have a Gold Cube which helps, but I use it as a double check. I also have 1, 2 and 3 gallon marks on my tank and have never ever been able see them while in flight. The camera is an option, but I opted for KISS.

The plastic tube full of fuel in the cockpit makes me nervous. I worry about how it will age. If not for that I agree that is the best way.

Jake
I use a calibrated dipstick and wouldn't be without it. It fits nicely behind the seat cushion.
Steve
Sonex 982

Bryan Cotton wrote:The plastic tube full of fuel in the cockpit makes me nervous. I worry about how it will age. If not for that I agree that is the best way.

There is tubing made specifically for this type of application. It is UV, Fuel, and Alcohol resistant. You don't use just any clear tube from the hardware store. I don't have a link handy so hopefully someone on here can point you to it. Mike Smith might have it on his builders website as I know he uses the clear site tube method. It would also seem to be an easy item to replace at each annual inspection if you were really worried about it deteroriating. Keep in mind that the fitting that connects the tube to the fuel tank is usually soldered shut and then re-drilled with a very small drill bit. This makes it so if the line becomes disconnected in an accident the fuel flow out of the fitting is greatly reduced. It also helps damp the fuel level in the site tube when the gas sloshes around in the tank.

Keith
#554

Thanks For all the help guys! Cant wait to get her in the air!