Some interesting points being raised here. To share a vivid example of tailwind effects, I fly light aircraft in gusty winds from a local field in Australia most weekends. The field is shared with a variety of homebuilt aircraft and gliders including a guy who flies a gyrocopter. One morning it was blowing a particulary brisk 30 knots straight down the strip when the gyro pilot taxied out, lined up and gave it full power down the strip. The machine became airborne in no time and climbed like a missile to about three hundred feet when ( no doubt inspired by the spritely performance) he cranked it around to fly downwind back down the strip ....when it promptly fell like a stone and smacked back into the ground about three feet from where he started the take off roll. Blades and bits of gyrocopter fly in every direction and he extracts himself with a puzzled look on his face.
Obviously the old gyro is more vulnerable under these conditons but turning downwind at low level in higher than usual winds certainly has it's risks. I can only compare it to ships losing helm ability in a following sea. It's all fluid ain't it.
cheers all
Vic