Autos and Rotor Stall
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We rolled throttle off, pitched for 60kts and counted to 5 before we got too nervous and bottomed collective and rolled throttle on. RPM was waaay down past bottom of the green. In retrospect it was a stupid thing to do. Proves to me just how forgiving the 269 really is.
Last edited by chopjock; 5th May 2010 at 12:50.
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es but one day it could save your life. Imagine having to "stretch" an auto to reach a safe landing site (because of trees or rough terrain etc). There you are, engine has failed, set up in the auto and you know you will not reach the clear area. What do you do? keep it in the green and fall short, smashing to pieces in the trees or raise the lever a little, increase to max airspeed, loose rrpm to below the min, then when clear recover to minimum by flaring like a b@2tard? I suppose the more you practice, the more you will know the absolute limitations?.
You seem to be advocating that we intentionally practice decaying RRPM below the power off minimum (the red line) to find the "absolute limitations". You might be playing devil's advocate, or you could be a half-wit, I'm not sure which. The reason the red line is there is that someone with access to a lot more data has already done something similar under controlled circumstances and decided that that is where the line should be drawn. Beyond the line is only more uncertainty (risk), not less.
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beyond auto limits
Chop Jock
Unfortunatelly,,,,the more you practice,, the closer you will get to meeting your maker!
Good luck,,, i think youve pushed your luck so far and lived to tell the tale.
Others have not
be warned!
HJ
Unfortunatelly,,,,the more you practice,, the closer you will get to meeting your maker!
Good luck,,, i think youve pushed your luck so far and lived to tell the tale.
Others have not
be warned!
HJ
Last edited by Heli-Jock; 5th May 2010 at 15:22. Reason: Not aimed at anyone first time round
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Chopjock,
While I understand the importance of learning to manipulate rpm and airspeed to alter glide path there's another side to this.
Not too long back a friend of a friend ran an a/c out of fuel through an unfortunate situation. He was trying to make an open field when the engine flamed out. He did just what you describe and bled rpm down trying to make the open field. I understand the psychological draw of trying to make that field rather than put it in the trees. Unfortunately he made the field just in time to come straight down 100 ft with no useful rpm. He died in the impact. Had he chosen to settle into the trees, pulling collective to bleed off his rpm and speed as he settled into the canopy, he might have survived.
Had a boss do that once. Got pretty beat up but he survived to fly again.
While I understand the importance of learning to manipulate rpm and airspeed to alter glide path there's another side to this.
Not too long back a friend of a friend ran an a/c out of fuel through an unfortunate situation. He was trying to make an open field when the engine flamed out. He did just what you describe and bled rpm down trying to make the open field. I understand the psychological draw of trying to make that field rather than put it in the trees. Unfortunately he made the field just in time to come straight down 100 ft with no useful rpm. He died in the impact. Had he chosen to settle into the trees, pulling collective to bleed off his rpm and speed as he settled into the canopy, he might have survived.
Had a boss do that once. Got pretty beat up but he survived to fly again.
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generally it is advisable to follow procedures written in POH/FCOM!!! 
maybe one can get several % more from machine(if one is highly experienced/talented/lucky), but its dancing on the edge...
maybe one can get several % more from machine(if one is highly experienced/talented/lucky), but its dancing on the edge...
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This must have been one of the tricky questions.
My answer would be "why would you want to check this?"
Operate within the limits on your meter or PFM and your'e good, most of the time...
Leave it up to Shawn and his folks to experiment for our well being.
My answer would be "why would you want to check this?"
Operate within the limits on your meter or PFM and your'e good, most of the time...
Leave it up to Shawn and his folks to experiment for our well being.
