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yxcapt
28th Jan 2002, 01:38
I've been flying a Bell 47G-2A1 with a boosted collective and a 47G-2 without a boosted collective. After flying the G-2 for the first 3 hours of the day and then switching to the G-2A1 I find my self overcontrolling the collective. I started to use some collective friction to help the situation. But this bothers me some. The hydrolic pump is engine (not transmission) mounted, so if the engine quits I'm auto-ing with out hydrolics. I'm beginning to think that flying with collective friction on (even though slightly) is bad idea.

It takes a good solid hour before I get use to the boosted collective, but shortly there after, fatigue (sic?) sets in and I never get as smooth as I like. On the other hand going from the G-2A1 to the G-2 is great.

I would appreciate your thoughts on using the collective friction.

Thanks

helimuster
28th Jan 2002, 04:04
It is only a matter of practice. We switch from B47/KH4 to B47G'S series all the time and it was a little tricky initially, I would suggest that once back in hydraulic assisted collective, you take aliitle longer and care when lifting and lowering the collective. After a while it will be an automatic reflex. <img src="wink.gif" border="0"> <img src="wink.gif" border="0">

Devil 49
29th Jan 2002, 14:24
I'd use a little friction, just enough that the collective didn't move very much before Mr Brain approved the change.... .You need to be smooth on the power all the time. If you have to auto, a little friction probably not significant against suddenly unboosted control.

UNCTUOUS
2nd Feb 2002, 18:03
I would strongly recommend keeping collective friction very low, especially at low-level.

Chasing a fox through gullies and ravines during some authorised NOE I over-enthusiastically over-cooked it, hit retreating blade stall (in a UH-1B), snap-rolled well past the vertical - and the only reason the aircraft auto-recovered is that the g snapping on caused the collective to drop for the floor.. .Why did I not have the collective friction done up? A smart chap called Laddie Hindley was my QHI for one trip and recommended I not have it wound on at low-level. I took his advice, even though I'd promptly forgot exactly why... and so lived to tell the tale.