It always amazes me when pilots get into the "left or right crosswind" question regarding American-type helicopters. Over on the "bad" forum, idiots are arguing it out right now. Clearly some of them literaly do not know how to fly.
So let me 'splain it to you...
People who advocate using a *right* crosswind on approach often cite the FAA diagram that shows that a crosswind from the left will produce "roughness due to tail rotor vortex ring state." The ill- or uninformed take this to mean that if you put the wind off the left, the tail rotor will immediately go into VRS and the helicopter will spin out of control and crash.
Despite what some pilots may think, the tail rotor never "stalls." It's ALWAYS working. It may get overwhelmed by the weathercock stability of the helicopter, but as long as it's turning, the tail rotor never signs off and loses thrust. That said, it's output thrust may vary, but that's what those things under your shoes are for: You can adjust them and keep the tail rotor thrust more or less constant.
If you get an uncommanded or unanticipated right yaw, just push FULL left pedal if you need to and hold it. At some point (probably before 180 degrees of rotation) the tail rotor will get a clean "bite" again and you're back in business.
Now, a left crosswind surely will cause roughness as the tail rotor momentarily goes in and out of VRS. But it never goes into complete VRS like a main rotor can. Because as soon as the tail moves even slightly, the relative wind into the tail rotor changes and it's out of VRS. "VRS" as it applies to a tail rotor is a momentary, transitory thing. As soon as you feel the nose do something you didn't ask it to do, push the left pedal until it stops! Push it to the stop if you have to. And hold it there.
Not only is the t/r going in and out of VRS, but in a front-left crosswind the main rotor downwash can cause interference as well. Your feet will be BUSY! You have to be on your toes, pardon the pun. But again, repeat after me, the tail rotor never stops working. ...Unless it stops turning. Then you're screwed.
But here's the important thing: A *left* crosswind will cause the nose of the helicopter to want to yaw to the left. This will reduce the need for left (power) pedal. Get it? The less left pedal you have to push, the less power the tail rotor is absorbing, the more power is available for the main rotor! In a strong left crosswind hover, you might not need any left pedal at all! Super!
Now, a *right* crosswind will cause the nose of the helicopoter to yaw to the right, necessitating more left pedal to compensate. And left pedal is bad, mm'kay? If you're heavy, and using a lot of torque on the landing (like up near the limit), pushing hard on the left pedal is just not a good idea. So if my ship is heavy, I'm going to choose the LEFT crosswind option if I can and accept the fact that I'm going to be working those pedals to keep the nose straight. But I do not fear that the t/r will go into VRS and cause me to lose control. Because that's not what happens.
You guys who think that a right crosswind is better on approach have never flown marginally-powered helicopters with weak tail rotors. Because if you had, you'd NEVER accept a right crosswind if you could avoid it. It's just dumb.
Those damn diagrams the FAA put out have sure scared the hell out of a lot of pilots. They equate T/R-VRS with tail-rotor stall, and that is simply not so.
The whole discussion on the "bad" forum was spurred by the video of that 206L pilot who crashed into the Hudson River by the W30th Street Heliport. He came to a big, high, downwind OGE hover, and then lost control of it, ending up in the water. He was the sole occupant, so we know that he was light. But he discovered that 206's like to point their nose into the wind, and they don't like it when you try and point their tail to the wind.
I've got a lot of time in LongRangers...a *lot* of time. And I've flown "straight" L-models in and out of W30th Street. A lot. I guarantee you...GUARANTEE that if he had lowered the collective just a smidge, and pushed FULL left pedal (and held it), and leaned the cyclic either forward or into the rotation a bit, he could have flown out of that uncommanded right yaw situation that he found himself in. But I believe he panicked (or simply went into brain-overload), assumed that his tail rotor had stalled, probably didn't push full left pedal, and crashed into the water.
I always say this: As we first start flying, we think that helicopters are hard to fly. As we gain experience, we come to realize that helicopters are pretty easy to fly. But they are also very easy to crash. And that never changes. No matter how much experience we gain, the helicopter never stops being easy to crash.