Hi all,
I have about 900 hrs R22, 5000 hrs R44 (Astro, Clipper I, Raven I, Raven II, Clipper II). Training, Pilot checks, maintenance, tunaboat, external load, name it....
a) Astro - I don't use the friction there, but will switch off trim in turbulence.
Find a moment where the cylcic is not hunting in turbulence, switch off the trim and you have a neutral point that holds. If you forget to switch the trim back on, you will find out on approach
.
b) Hydraulics:
Depends - whether the machine is new or "run in":
At some point Robinson used rather tight rodends, that would need some 300 to 600 hours to loosen up. It was rather stiff, no friction needed. In a hover it was impossible to have a soft touch. I would have to apply a good grip to make the brake-out bump transparent. You could let go of the cyclic and it would not move at all.
Robinson changed the rodends on newer ships and they are rather nice now.
There is no or very little brake-out now, but a rather smooth drag on the controls. In a new helo you still can let go of the cyclic and it holds.
In well used hydraulic ships the rodends are loose (but no play, please!) and the cyclic becomes sensitive without a little friction - LITTLE friction, just enough to introduce a little drag, there is no brake-out force, as this came from the new rodends not the hydraulics. I am only refering to the rodends BEFORE the hydraulic cylinders.
No friction means the cyclic will fall wherever its own weight will push it if you let go of the cyclic...
As mentioned before, when the air gets rough a light helo like the Robinson will cause some pilot induced turbulence, allthough it is not half as bad as a EC120 or AS350.
Eurocopter instructors will insist to apply enough friction to keep the cyclic from moving in case it slips your hand. Personally I adjust it depending on weather, intended use, mood, what foot I got on the floor first that morning, whatever...
Gentleman, remember, for every pilot out there there will be a different set of rules, settings, preferences to apply.
Try it out and use it as you like, it also depends on the machine.
Those who insist, that friction is "dangerous", it is only dangerous if you lock it! In some occasions it may even prevent you from a spontaneous (panic) move - liek avoiding a bird you didn't see inthe first place...
No trim in the hydraulic ships!
Same for the collective in the Robinson.
Friction should be adjusted in a manner, that full friction application still lets you lower and raise it - never fully locked!! If you need more friction than that, put it in the shop!!
Also on the hydraulic collective, there should be NEVER a climbing collective!
(Actually in the electric trim one either....)
A decending ("heavy") collective should be only very little, basically induced only by its own weight (collective lever) with all the friction off.
If it is really heavy, into the shop!
It is may be some tedious work on the electric trim helo to get the collective right, but this is a "good" indication of bad rigging if the collective is excessivly heavy.
Hope it helps!
3top
