S76A++ Unusual Snag. Help Required.
Hi Chaps
For those of you who are seasoned S76A++ drivers I hope you can possibly help with regards a snag that has had my engineers confused for a couple of weeks now.
Symptoms:
Whilst in flight there is an unusual amount of feedback through the cyclic. Almost as the helicopter is doing it's own thing. The feedback is as if someone has grabbed hold of the cyclic and moving it around eratically. It appears to be more common to the pitch than to the roll. However, I do experience unusual feedback in the roll as well.
Trouble Shooting so Far:
1. No 1 AFCS Channel is disengaged, symptom persists
2. No. 2 AFCS Channel is disengaged, symptom persists
3. All common denominators to the AFCS have been isolated. Heading Control removed, PBA removed etc etc. Problems still remains.
The problem dissapears when both AFCS Channels have been disengaged. Now we have swapped every component we can think of with other aircraft. the problem remians with the aircraft. I am beginning to think there may be a short in one of the looms to the AFCS.
Anyone got any idea's or have experienced similar problems. Please give me a clue as to how I can resolve this issue.
Regards
HJ
PS We are not operating the Helipilot AFCS system.