My thoughts are that all of you that experience this wiggle are ex Bell pilots.
I have never had the problem, nor have my students.

Around all helicopters close to the ground there will be patterns of air flow that are random due to a multiplicity of reasons. These air flow patterns will effect the tail and main rotors and as pilots you are trained and practiced in hovering. May I suggest more hovering practice with a relaxed and alert brain!
Coanda effects and the like are possible reasons. Some tail booms have strakes, some have had strakes and have had them removed, some do not have strakes. I think strakes were/are fitted for other reasons.

Head Turner:
There are lots of those who experience this who are not ex-Bell pilots.
Seems to be unique to the AS-350 series, although I have seen something similar, with less intensity in the Bell 407.

My company's looking at buying a Squirrel that comes with both high and low skids.

Planning to fly it in both configs and see but apart from the obvious change of ground clearance and dynamic rollover potential, what else is different when flying the low skid version ? Less 'wiggle' ?

All my time is in low skid models, and IME the low skid makes it harder to set one down gracefully. Also, the tail skid is below knee level when on the ground, and it is entirely possible to strike the ground with it when hovering with an aft CG and/or a tailwind. Avoid low skid gear at all costs.

Thanks GLS,

Useful to know, especially as many of our landings are confined and high skid model can be 'squirrely' enough.

Is it nothing to do with the front and rear legs being a different length, and the bushy tail moving from side to side as they run???:confused: :O :O

Is there a difference between grey and red versions as well??

The answer is yes, they all do in a certain part of the flight envelope - probably the cruise.

Certainly Brit military Principles of Flight teaching is thus: put simply, tail rotor roll (ie hovering left or right skid/wheel low, depending on main rotor direction of rotation) IS a consequence of the different height of main and tail rotors and is designed in to avoid being left (or right) side low in the cruise. As the fuselage pitches further down with increasing speed, at normal cruise, you have a (laterally) level floor. Much more comfortable, and less disorientating in IMC. However, inevitable design compromise means that laterally level fuselage in cruise (tail rotor and main rotor level) inevitably means in the hover when more nose up (tail rotor and main rotor NOT level), there is a lean to one side (towards the advancing main rotor blade).

Check out side on pictures of most conventional helos in the cruise to see that tail rotor is usually level with (or closer to) the main.

And I did say "put simply"!! With due consideration for Danny's bandwidth.

Astar rotorhead direction?
 

Surely it has been asked before, but what's with the clockwise direction of travel for the rotors?
Just the french engineers being french??

Steve,

Looked at many single-rotor Russian helicopters lately?

Maybe anti-clockwise is just the Americans being American...

Jonathon Swift wrote a whole book about the ability to argue about arbitrary things!
As lately seen, Americans go Right when more power is added, the French and Russians have always gone Left!

There is obviously no 'better' way to have the rotor rotate.
Legend has it that the French got one part of a Flettner machine as war reparations and used that for their engineering, and since it turned clockwise when viewed from above, they stuck with it. Given the relative maturity of the French rotary wing engineering prior to the second war (they had the first hovering helicopter in 1909) that's a bit far fetched.

Anything to do with the relative conventions of piston engine direction of rotation in the early days?

But that had two contra-rotating rotors, didn't it :confused:

Hi,

Have a look here

http://www.pprune.org/forums/showthr...hreadid=105978

Cheers

ATN

AS 350 B-3 Engine Failures
 

An As-350 B-3 recently experienced an engine failure during takeoff in Sierra Vista, AZ. Has anyone experienced similar difficulties with this model machiine? We are currently operating a B-2 and are due to get a new B-3. Our pilots are expressing concern with opering this new aircraft in the mountains at night.

None that i have heard of in Oz, BUT

flying any single engine helicopter over mountains at night is something you SHOULD be concerned about. At least tell me you will be using NVG?

Statistics can be bent anywhich way, but engine failures are not a rare occurence, and rarely are failure statistics recorded where the failure does not result in damage or injury. For the pro single engine mob that are bound to be wound up by this statement: when it all goes quiet at night, out to sea, IFR, over inhospitable terrain or day care centres, console your selves in the statistics of how safe single engines can be.

And how much money was saved by the operator to put you there. Who knows, maybe they put it all into accident insurance for the sake of your loved ones!
:8

We have a very solid track record with tens of thousands of single engine flight hours. Good maintenance and professional pilots. We do have a few intermediate twins but they are not capable of operating even duel engine at the altitudes and temps we experience. OEI capabilities are even more limited. No we are not presently NVG's but we are working on it. Any knowledge or increased understanding of the machines we operate goes along way toward keeping our operation safe. Thanks you for your input.:ok:

Great machine, great engine. ****ing computer. I'm flying one of the first B3's to come off the line. We're within (knock on wood) 150 hours of engine overhaul with no problems. Unscientific observations point to Texas built machines having problems, Canadian built not so much. Please Eurocopter, lose the DECU, or FADEC, or whatever you're calling it now. That would make it the near perfect machine.

They're probably using a 386 :yuk:

Phil

A-Star "Jack Stall"???
 

This term "jack stall" is a new one on me....anyone out there that can enlighten me? Was used in disussing a recent 350 accident and was related to large agressive control movements and the inability of the controls to function as expected or demanded.