The down wind turn.

[birdy]

Yes, i know, its a badly flogged horse, but theres sumthn that is dangerous bout turning downwind, specialy at low altitudes.A good friend of mine who is new to gyros, [and flyn generaly] has found out the hard way that there IS a danger. He"s got a compleatly totaled machine to prove it. [ with the only things salvageable be"n the 912 and the stick grip.] But, thank whoever you like, he didnt get a single scratch. :yes:He has just over 100 hours in a machine i"d describe as a perfect mustering machine, a real pochet rocket. Single open machine with 26" extru blades and a trusty 912. Perfect. He"s wot sum people call gifted wen it came to flyn, coz he "clicked" so early in his flyn time, with beautifuly smooth exicution of every manouver he did, and was careful and precise.So, why did this bloke smash this machine while do"n nuthn but a routine turn? To put it simply, he chose the wrong time to turn down wind.His mistake wasnt coz he was incompitant, complacent or reckless. It was coz he turned downwind INTO A STRONG WIND SHEAR. [ this machine could climb at better than 1800 fpm.]This air he hit was decending fast, at less than 200" alt and as it neared the ground, it accelerated in the same direction he was traveling, downwind. So the further he flew into it, the stronger the virtical component became, AND the stronger the tail wind got till he reached the point where he had no AS, No lift and no alt, no options, but he had a dangerously high ground speed.

[NiqueNaque]

Thank you Mr Birdy

[Adrian S]

Mate,Well said. Adrian

[asra]

Thanks for the post - couple of questions...It was coz he turned downwind INTO A STRONG WIND SHEARWas this a day with strong broken thermals? Low inversion? High winds? What type of conditions are present when this situation is more frequent?i remember thinkn to meself, "id better ring ol mate tnite and hava yarn bout these before he hits one."What would you have said to him, given he still probably had to work that day?If you know wot to do, your likely to get out of it, What do you do?Dave

[birdy]

Was this a day with strong broken thermals? Low inversion? High winds? What type of conditions are present when this situation is more frequent?There was nothing special bout the conditions he was opperating in mate. Thats the trouble, alota people assume that coz the air is glass smooth, theres not go"n to be any gremlims about.Some of the strongest/sharpest shears iv hit were on glass smooth evenings, just after sundown. I havet yet figured wot triggers them, but they certainly scare the crap outa you, coz its the last thing your expecting.The most common ones seem to occure on days wen the min and max temps are extream and theres no wind.[ like 0c in the morning, and warmn up past 30/35c in the day.]This wether condition produces the STRONGEST ones, specialy over flat country with consistant cover and no wind.Wind will mix the layers of air as the day warms up, not alowing it to stratify so strongly.Generaly, if theres any strong uppers about, theres go"n to be strong downers too. Wot goes up must come down.

[RossM]

I remember reading years ago in a CASA/flight??? magazine where people tell of their experiences. A pilot up in the North west was flying around when he saw a trail of dust. Thinking it was some poddy dodges he went to investigate. He was suddenly in a massive downdraught. He applied full power, but the Cessna just kept sinking. When the plane was just off hitting the ground, the plane responded in time and luckily avoided a crash. The trail of dust was not from a vehicle driving along but the wind shear hitting the ground.