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Fuel Flow Test + angle

HansLab

Well Known Member
In the PAP I can read the procedure, however I don't see need to raise the front (my KitFox had to be raised +5% above the max take-off angle - some 20 degrees from level).
Am I missing things?
 
The advisory circular for experimental aircraft testing 80-99B, states to do flow testing at 5º above the highest anticipated climb angle. Understanding that Van's designed the RV12 for E-LSA, so therefore they've already done flow testing to ensure fuel flow at that highest anticipated angle.

I did my RV12 E-AB, so I did a full fuel flow test. I have found that my 12 can climb at 15º for a while, so 20º makes sense for testing.

The PAP fuel procedure is really just to help you calibrate your fuel gauge and mark your fuel tank for minimum fuel, not perform a full fuel flow test.

If you pull the RV12 tail to the ground, your nose angle will be 15º up. You can certainly put blocks under the main wheels to get to 20º if you desired, which is what I did. Just note that this testing was done at whatever angle and minimum fuel available at whatever angles you ended up with and keep that in the POH for future reference.

I'm sure the pundits will be along shortly to restate this more eloquently...
 
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Yes, Ron, this was what I was looking for. Thanks for sharing. 20 degrees looked fine as well, I'll dig a hole next to the runway again (the one from testing the Kitfox is still there...;)).
Could you share the amount of fuel you put in to be able to reach the fingerstrainer in that angle, please? I guess it should be quite a lot?
[edit] but reading along the reactions I figure just that is the 4,5 Gallon 'reserve fuel'. It isn't reserve, but sufficient to keep the fingers trainer from running dry (and have the pump suck air).
Thanks everyone!
 
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I believe an older RV-12 with the right hand side fuel tank is rated at about 4.5 to 5 gallons of reserve fuel, if built to E LSA standards.
 
The legacy RV-12 tank is fully usable to the last drop. POH states minimum of 4 gallons for takeoff so tank doesn't un-port in an extended climb.
 
That is because the test as described in the PAP is taking an all wheels on ground attitude into account. If it passes the test as described, the entire system is considered to have passed.
 
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Hello Dave

You will need to reference many things in the PAP even going EAB with your RV12. I suspect you will still use the flaperon system, the stabilator with Anti-boost tab (also the trim tab), and both will have setup with adjustment specs to follow. These are a couple things that came to mind but there are likely others.

Enjoy the build!
 
Hello Dave

You will need to reference many things in the PAP even going EAB with your RV12. I suspect you will still use the flaperon system, the stabilator with Anti-boost tab (also the trim tab), and both will have setup with adjustment specs to follow. These are a couple things that came to mind but there are likely others.

Enjoy the build!

Thanks for that information. I was wondering where to find such specifications.
 
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