90° tail blow out when pushing hard

[ic-racer]

When I have a blowout I check the flight log. If the rudder limit is reached, then it is an issue with Tail RPM/Tail Throw/Tail Blade Area. Otherwise it is the other stuff; Rudder Gyro Gain/Servo Speed, Driving Hz, Voltage, Torque.

[Coco66]

Very good one, ic-racer, I'll try that next time I fly.

hookedonflying, first time I had the tail blow out I DID crash, but I was fast with Hold and on high wheat, zero damage. Other times I tested, I was more ready with Rescue

[donaldsneffe]

You said, removing the clamp removed the blow-out but caused vibrations.

Try to sand the clamp inside - I did. So that the tail pushrod only touches the clamp slightly when in nearest position (what is 90° servo arm). This highly increased my tail-behaviour.

But I did not have any vibrations when doing a test flight without clamp.

Walter

[myxiplx]

If you had a blowout in fast backwards flight it could be that you didn't have enough tail authority. What headspeed are you running?

[Coco66]

Originally Posted by myxiplx

If you had a blowout in fast backwards flight it could be that you didn't have enough tail authority. What headspeed are you running?

Well, actually I don't know. According to my calculations I should be running around 4000, 4500 and 5000, and experiencing blowout with the first two at least. I run an 11T pinion on a 5500kV motor, with three TCs of 71%, 82%, 91%.

But... my Magic Mirror only goes up to 4200, two Android apps I tried, which served me well in the past, give strange inconsitent results (could be the plastic blades?), and an Hyperion sensor I tried with Spirit gives "jumping" results. Ordered and HW sensor, let's see.

[donaldsneffe]

Originally Posted by Coco66

(could be the plastic blades?),.

No.
Frequency is independent from blade material

Walter

[hookedonflying]

I use Headspeed Tachometer and it works great. Consistent with small or larger helicopters.

[scoio]

Originally Posted by Coco66

Well, actually I don't know. According to my calculations I should be running around 4000, 4500 and 5000, and experiencing blowout with the first two at least. I run an 11T pinion on a 5500kV motor, with three TCs of 71%, 82%, 91%.

But... my Magic Mirror only goes up to 4200, two Android apps I tried, which served me well in the past, give strange inconsitent results (could be the plastic blades?), and an Hyperion sensor I tried with Spirit gives "jumping" results. Ordered and HW sensor, let's see.

I am using the HW sensor, and rpm are spot on in comparison with rpm telemetry....

[Coco66]

Originally Posted by scoio

I am using the HW sensor, and rpm are spot on in comparison with rpm telemetry....

I am surprised of my Hyperion sensor giving strange results since it always worked well for Spektrum telemetry. Never really seriously tried it with Spirit Governor though.

[Coco66]

Just as a note, now my tail works perfectly with the DS95i and headspeeds of 5000+

[mba83]

My tail also worked good with DS95i. But I could totally feel the extra weight. The heli felt like a big in the air.

So eventually I went back to DS76t - which required I fix my tail issue (bad pitch slider, in my case).

[jrman83]

Possibly the extra torque from the new servo masks a problem you may have.

[jrman83]

I noticed I was starting to get a little tail blowout on one of mine. After looking it over I found that my belt had loosened up. Not sure how. I generally run a loose belt.

[Not_Here]

Great info here for future trouble shooting and solving issues with blow out.

I love HF!