Question on downwind autorotations
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Probably shoot myself in the foot for this but.....I did a variation of this many moons ago in an R-44 but only with less than 10 kts of wind.
Ride the extended glide speed and rpm all the way down to say 30-50 feet. Start to scrubb off speed and your sink rate goes to zero, as your airspeed comes back to 45 ish do a peddal assisted right turn into wind and keep scrubbing speed through the turn and the rpm will recover to mid-high 90's. The speed reduction in the turn keeps your sink rate very low and we would end up with a zero speed arrival into wind without ever doing a pronounced flare.
Never put one on the ground, always did a power recovery, but it would have been easy to do.. but what for? For us it was just an excercise in coordination and reading/modifying/playing with airflow and sink rate, keeping air flowing up through the disk especially in the turn. Having zero sink rate before starting a turn was the key to our particular experiment.
Keep in mind we didnt just go out and try this out of the blue....we worked slowly up to it doing hundreds of autos. Would it be useful in real life, hell no. ...did we show it to all the pilots, hell no. Would I/could I do it now...not even close, was a training pilot back than so had the opportunity to do a lot of autos.
Another topic....how about a 40 kt auto at 90% RPM with an (almost) zero flare touch down.(all done into wind)
Ride the extended glide speed and rpm all the way down to say 30-50 feet. Start to scrubb off speed and your sink rate goes to zero, as your airspeed comes back to 45 ish do a peddal assisted right turn into wind and keep scrubbing speed through the turn and the rpm will recover to mid-high 90's. The speed reduction in the turn keeps your sink rate very low and we would end up with a zero speed arrival into wind without ever doing a pronounced flare.
Never put one on the ground, always did a power recovery, but it would have been easy to do.. but what for? For us it was just an excercise in coordination and reading/modifying/playing with airflow and sink rate, keeping air flowing up through the disk especially in the turn. Having zero sink rate before starting a turn was the key to our particular experiment.
Keep in mind we didnt just go out and try this out of the blue....we worked slowly up to it doing hundreds of autos. Would it be useful in real life, hell no. ...did we show it to all the pilots, hell no. Would I/could I do it now...not even close, was a training pilot back than so had the opportunity to do a lot of autos.
Another topic....how about a 40 kt auto at 90% RPM with an (almost) zero flare touch down.(all done into wind)
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Another topic....how about a 40 kt auto at 90% RPM with an (almost) zero flare touch down.(all done into wind)
Mmmm, interesting. Relatively low r.o.d., no loading the disc at the bottom to increase rrpm before you cushion it so not much cushioning factor before the blades slow down too much. I would imagine a fair bit of skid bending without a lot of headwind. Done many constant attitude auto's at 40 kts and always needed to flare quite a bit at the end. Would the 90% rrpm eliminate the need for a flare??? Never tried it.
Mmmm, interesting. Relatively low r.o.d., no loading the disc at the bottom to increase rrpm before you cushion it so not much cushioning factor before the blades slow down too much. I would imagine a fair bit of skid bending without a lot of headwind. Done many constant attitude auto's at 40 kts and always needed to flare quite a bit at the end. Would the 90% rrpm eliminate the need for a flare??? Never tried it.
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just finished ATP
Never heard of such a thing. I have experience in U.S. military and civilian flying and this sounds like a good leg pulling exercise. However, sometimes instructors (fortunately this is extremely rare)
can't resist inventing their own maneuvers or demonstrate what they shouldn't, like the low g pushover in the R44.
can't resist inventing their own maneuvers or demonstrate what they shouldn't, like the low g pushover in the R44.
Avoid imitations
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Another topic....how about a 40 kt auto at 90% RPM with an (almost) zero flare touch down.(all done into wind)
I have to ask the question WHY would you do a 40 kt EOL at 90% NR? The only reason fro drooping Nr in auto is to increase range which is clearly not needed if you are doing a 40 kt auto. All you are doing is reducing the likelihood of your survival.
After reading some of the posts on this thread it seems there will soon be a chapter in the Darwin Awards solely for 'really clever and innovative helicopter pilots whose genius was misunderstood by the mainstream helicopter world'.
After reading some of the posts on this thread it seems there will soon be a chapter in the Darwin Awards solely for 'really clever and innovative helicopter pilots whose genius was misunderstood by the mainstream helicopter world'.
At 40kts and 90% Nr giving a relatively slow rod and forward speed, a constant attitude with little or no flare at the bottom (depending on wind speed), it sounds like an alternative technique for night time EOLs? (I was taught 45kts, Nr in the green, no flare but lift the lever at the bottom to cushion impact).
Hovering AND talking
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it sounds like an alternative technique for night time EOLs?
Not sure about 90% RPM
Cheers
Whirls
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Just to keep this urban myth alive can anyone suggest the maximum wind speed for this? 
That way after you have completed your ground run, you will have worn the skids, belly panels and possibly the also the backside out of your strides.
This is going to be exceptionally handy as your boss, or the A/C owner, or the one in the same, will be easily able to work which area of your anatomy to kick until your nose is also bleeding.
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it sounds like an alternative technique for night time EOLs?
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After reading some of the posts on this thread it seems there will soon be a chapter in the Darwin Awards solely for 'really clever and innovative helicopter pilots whose genius was misunderstood by the mainstream helicopter world'. 
