Fuel Flow Test

[egodfrey]

RV10 builders/pilots,
I am pondering the fuel flow test as outlined in AC90-89B, Section 11, Par 1-19.e(1). For those of you who may have performed these tests, what climb angle did you use and how did you obtain it. I did a test with weighing down the tail and the best that I could get was about 12 1/2 degrees when the tail tie down hit the hangar floor. I am thinking about raising the main gear off of the floor, but was not sure as to what height would work out the best. I did place a call to Van's to see if they had a "standard" of unuseable fuel for the RV10, but the reply that I received was that it was up to the builder to determine that. Thanks for any information to help me get by this step.

Ed Godfrey

 

[rocketman1988]

Test

I just did this. I used flight attitude for one test, with three iterations.

Then I rolled the nose wheel up a car ramp and came up with 13.5 degrees NU...and yes, the tail was pretty much on the ground. YMMV, as I have EFII with dual electric pumps...

I performed the same test, with three iterations.

The average of the three from each pitch is what was used to compare to the minimum recommended fuel flow.

As a side note, I think that the nose DOWN pitch would be a bigger concern as it would be possible to unport the supply. In a nose UP scenario, all fuel flows TO the supply line.

I did find that nearly all the fuel was useable in level attitude. I measured what was left when the pump couldn't draw any more...it was about 3 ounces...