PilotLight

My Feedback: (1)

Flew numerous flights yesterday and had no problems. Today, with no changes made besides fresh batteries, the Axe is jumping up and/or down. This is getting frustrating. It will suddenly jump up while bogging down the motor. Then, suddenly fly normally. Next time it might jump down, but usually up. The third flight had half as many jumps as the first flight. Maybe the grease is thick around the swashplate and as it warms up, it thins out. The heli sits in a 50 degree hangar so the gyro doesn't change temps while I'm flying.


With all the other complaints on here about jumping up and down, somebody on here has to find the cure.

[:@][:@][:@]

Shadow99

I no longer use grease on any of the main shaft/swashplate areas, use only light weight oil Tri-Flow 3in1 is BEST. I found the jumpyness returned when I applied some Kulber NCA-15 grease onto the shaft where the swashplate slides. Wiped it off and reapplied the Tri-Flow, no issues.

Shadow

PilotLight

My Feedback: (1)

That could be the cause. I didn't change anything and went back out to fly 3 more batteries. Not one jump. I did move the swashplate up and down the full travel to try and spead out any accumulation of grease.

PilotLight

My Feedback: (1)

This problem is driving me insane. Flew 4 flights today and it was still there. I removed the blades, balanced the head with just the flybar paddles on. Had to slide the flybar over just a touch. I think it moved when I was adjusting some negative angles to the paddles. Anyway, it was flying smooth as silk again (vibration), except for the pulsing up OR down. Held the heli in my hand and disconnected the tail motor. Ran it up and switched into idle up. While it was in neutral pitch it was fine. As I added positve pitch, it would jump to positive pitch and really try to fly up and bog the motor. Then I would go back to neutral. Then, as I went negative pitch, it would jump to pushing the heli down and bog the motor. I could see the slide block jumping one way or the other. Tried tightening the screws that hold the seesaw. Took it outside and had no change. Its like any airload on the blades make them try to TWIST towards whichever way they are creating lift. Add a little positive pitch and they want to twist to LOTS of pitch, add negative and they Jump to LOTs of negative.

Which part do I replace? I've got every part ready except the slide block.

PilotLight

My Feedback: (1)

I have tried an experiment with adjusting the starting position of the blades before the helicopter spools up. By adjusting the blade towards the trailing edge, most of the mass of the blade is behind the hinge point of the blade. This helps the blades to weathervane into the plane of rotation of the blade instead of trying to twist into positive or negative pitch. So far, it seems to help.

Attached is a simple picture of the change in area of the blade if it is rotated back a bit. Yes, the centrifugal force will pull it back into alignment, but it will not get all the way because of friction in the blade grip.

When I positioned the blades forward of the hinge point, and held the heli in my hand, it would jump neutra pitch, to positive, to negative with just the slightest throttle changes in Idle up mode.

Edit: the green area shows the increased area behind the hinge point when the blade is lagging.

mikezell

If the slide and your linkage are free...

Try turning off your cell phone. When mine was on the heli would suddenly drop or jump.