Warp Drive pitch settings

[the Drew]

Does anyone know where I can find the proper pitch setting for said prop and Rotax 912 ULS for the Kitfox 7? I am not getting near the static RPM that I should, and want to start checking with the prop pitch. Thanks in advance.


Kenny

[SkyPirate]

2 blade or 3? tappered tip or square?

[the Drew]

It is a three blade, and the ends are squared.

[SkyPirate]

if I remember right ..Slyfox ..(Steve) was using a warp 3 blade on a 912,..he has switch out to a Medium IVO now ,..but he would have better numbers for you .

Mine was a 3 blade tappered tip on a 582 E box ..set at 12 degree's
450 ASL..average temp 80 F.

from what your saying you have too much pitch on your prop,..it takes very small increments in degree change to change RPM's with the warp,.. if your less then 500 RPM from your desired RPM,..I'd go 1/2 degree changes until you reach what your looking for ..it's a little time consuming with the warp..
but it will take less time with small adjustments then with big ones going back and forth on changes.

[the Drew]

Thank you Slyfox.

I rechecked my settings last night, and I was set at 16 deg. I don't even know where that # came from. I was only getting 3300 rpm or so. I've reset the pitch to 10 deg. and will see what I get later this morning.

[Dorsal]

Please post your results, I have the same set-up and I am about ready to run the engine.

[the Drew]

I did call Warp Drive and they told me 11-13 deg. I also talked to John McBean at Kitfox Aircraft. He measures at a different location than the tip, but his setting correlated exactly to the Warp Drive setting measured at the tip.

Fess-up time. I am using the Grand Rapids EIS system. As I was re-reading everything, I found a small hidden paragragh which stated that the EIS must be calibrated for the 912. So out to the hangar I go with book in hand and follow through all their steps (not really that many) to check the calibration. It was not set correctly. I made the correction, and now have all kinds of RPM.

My pitch setting ended up at 13 degrees, measured a the tip. 5380 RPM static full power.

On another happy note, we passed our airworthiness inspection this morning.

[Dave S]

Hey Kenny,

That is great news. There is that little thing about instrument calibration - those of us who responded obviously made some assumptions about the original reported indicated RPM; but you got 'er now!

FYI - I sort of decided through experimenting that measuring a few inches in from the tip and interpolating the difference between the protractor reading and the pitch the tip is supposed to be set at helped a bit with the accuracy of the setting from one blade to the next - since I have the tapered tip - it seemed a bit awkward trying to get a consistent reading from blade to blade at the tip since there is such a short chord to work with - figured that would be less of an issue with the non-tapered blade anyway.

Really great hearing you got the airworthiness certificate - that is a major milepost to your progress.

Do good on that first flight now!

Sincerely,

Dave S
k7 Trigear
912 ULS Warp

[wadeg]

Have you flown yet and if so, how do you like the 13 degrees setting on your prop. Might reduce my pitch to help me get down steeper. At idle it really wants to keep going and going. Would love to get it to the point where I can "cut and plop".

[the Drew]

I have flown and find like you, that at idle power, it carries me too far. What would you suggest if anything? Perhaps reducing to around 11.5-12? Aside of that, it's got plenty of scoot, and having a blast.