T-Rex HDE for AP Pitch/Throttle curve suggestions

[ncpiperpilot]

I have a T-Rex HDE that I am setting up as a AP platform. Just waiting for my Askman mount to arrive :D

specs:
Align 335mm Pro woodies
Align 430L 3150 kv (not the 3550)
Align RCE-BL35G Esc

currently a 13T pinion, I was planning to go to 11T, but I ordered the wrong shaft size (HZ020 set is for 2.3mm shaft - DUH). The 11T should give me about 2280RPM, the 13T is about 2700RPM (calculated at 90% eff)

Any one have pitch/throttle curves they are happy with for lifting weight with these blades?

Thanks...Bill

[Tonystott]

I have a T-Rex HDE that I am setting up as a AP platform. Just waiting for my Askman mount to arrive :D

specs:
Align 335mm Pro woodies
Align 430L 3150 kv (not the 3550)
Align RCE-BL35G Esc

currently a 13T pinion, I was planning to go to 11T, but I ordered the wrong shaft size (HZ020 set is for 2.3mm shaft - DUH). The 11T should give me about 2280RPM, the 13T is about 2700RPM (calculated at 90% eff)

Any one have pitch/throttle curves they are happy with for lifting weight with these blades?

Thanks...Bill
Once you fit the 11T with the correct shaft diameter (mine came standard in the CDE kit, didn't you get one in yours?) there is no need to change curves.

[ncpiperpilot]

Well...

I picked the HDE up used, yes it's supposed to have one, but this one only came with a 13T.

Which curves do you mean not to change :?:

My current Norm curves are really from a 3D type set-up
Th 0 / 25 / 50 / 75 / 100
Pi -2 / -1 / 0 / 5 / 10

The book says something more like
Th 0 / 40 / 65-70 / 85 / 100
Pi 0 / 3 / 6-7 / 8 / 9-11

Thanks,
Bill

[Tonystott]

Well...

I picked the HDE up used, yes it's supposed to have one, but this one only came with a 13T.

Which curves do you mean not to change :?:

My current Norm curves are really from a 3D type set-up
Th 0 / 25 / 50 / 75 / 100
Pi -2 / -1 / 0 / 5 / 10

The book says something more like
Th 0 / 40 / 65-70 / 85 / 100
Pi 0 / 3 / 6-7 / 8 / 9-11

Thanks,
Bill
Your norm curves are not far wrong (certainly not 3D though, which would have throttle like 100 95 90 95 100 and pitch -10 -5 0 +5 +10

I have my Norm throttle set at 0 30 65 80 90 (no need to go for max headspeed for aP) and pitch set at -3 0 0 5 10

I have the second pitch one set at zero so that dropping the throttle doesn't slam the heli into the ground.

But I am newish at this too, so please keep asking around :)

[enigma]

run governor mode and a straight curve with around -5 on the bottom to handle gusts, etc. You always want some negative available and constant headspeed is more suitable for ap. just my .02

[ncpiperpilot]

Tony,
Thanks....your curves are pretty close to mine with a bit more Throttle on Norm. (My Norm curve for 3D is what I quoted, my Idle1 curve looks just like yours...throttle 100 95 90 95 100 and pitch -10 -5 0 +5 +10)

Enigma,
Thanks...good thoughts...Gov mode might make it much smoother. probably don't need -5 though with all that weight though :mrgreen:

More actual pitch curves are appreciated from folks along with your experiences...

Thanks,
Bill

[Tonystott]

Hang on a sec! you don't ever want zero thottle in 3D! I think you might be mistaking the terms. 3D is usually what idle-up is for. Normal is basically for spooling up, and as Enigma says, for AP, maintaining a constant headspeed is a good idea.

From what I have read, you need lots of neg pitch if you ever have to do an auto with an AP ship, especially with light blades like a trex wears, as they will stop unless you can keep them spinning with neg pitch, so they have hopefully enough energy when you give it full positive pitch just before it hits the ground. Might not save an AP Trex, but the hole in the ground won't be so deep :)

[ncpiperpilot]

Tony,

OK..terminology is probably confusing things...

What I meant by a 3D setup includes both the Norm and Idle1 curves. Of course for actual 3D flight you don't have zero throttle. BUT ideally you want to have a setup that allows you to switch in the air from Norm to Idle1 without the Heli ballooning or sinking on the switch flip.... Thats why I called that Norm curve a 3D Norm curve. If you use the settings in the Align Manual for Norm and Idle1, you will NOT get a smooth transition when you flip the switch (mid-stick would give you a pitch change from 6-7 deg to ZERO).

I hadn't thought about an Auto w/ AP on an electric - probably an oversight on my part. You are right a lot of Neg pitch would be required to keep that head spinning.

Thanks
Bill

[enigma]

thank you :cool: