Helicopter max climb altitude
Love to post more on that ToW thread but it got to hard with slash & burn tactics removing to many posts, rewordings & photo deletions.......see my thread count, I'm still hobbled on half a stump 
All the very Best to You T18
Hi VF
Sorry I missed your reply I’ve been busy with work
That explains it well. I was told O2 above 10K on my pplh
but thought you guys doing it all the time may not use it all the time as you explained.
Unlikely I’ll ever be that high.
Thanks R
Sorry I missed your reply I’ve been busy with work
That explains it well. I was told O2 above 10K on my pplh
but thought you guys doing it all the time may not use it all the time as you explained.
Unlikely I’ll ever be that high.
Thanks R
Be a little careful with Fred North's "record" - it is a little "shy" on "evidence". i.e. unofficial.
Flying to an oil rig 180NM away with predominant tailwind of more than 30kt and no refuel offshore, climbing to up to 9000 or 10000ft coming back to take at least a crosswind makes sense for me.
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I've been high twice in an R22... Once going from Hartford, CT back to Boston... There were really high tail winds aloft so I climbed to, I think it was 11,500 ( this was in the eighties, so I don't remember exactly ). We had LORAN in those machines so I know I was doing 140 knots over the ground.. which is pretty good for an R22. When I got handed off to Boston the controller asked aircraft type and did the ATC equivalent of a double take when I told him R22.
Bringing an R22 home from the factory I went high in West Texas for the same reason. In that case every time I would push the stick forward the entire aircraft would shudder and the stick would push back, even though there was plenty of stick travel left. After a few repetitions I finally thought to check the VNE chart... Realized THAT'S what retreating blade stall feels like in an R22... ( Tim Tucker at Robinson always said retreating blade stall at sea level is 150 in an R22... And I mostly fly at sea level... So it took a while to connect the temperature and altitude to the fact that I was flying way too fast.)
Finally coming out of White Plaines ( just north of New York City) IFR in the B206L3 I fly ( probably in the late 90s?) IFR, ATC climbed me to 12 for a little while before turning me east and letting me descend... But I was IMC so I don't remember anything unusual except the hands on the altimeter looking a little strange... ( and that it took a while to climb that high... I was heavy with fuel ).
The only time I found it really disturbing was that first time... The horizon was in an unusual position on the windshield, and I remember that my attitude flying sucked. No attitude indicators in R22s in those days, so that made it a little more... challenging to keep the machine level.
I guess that's pretty pathetic compared to VF!
Bringing an R22 home from the factory I went high in West Texas for the same reason. In that case every time I would push the stick forward the entire aircraft would shudder and the stick would push back, even though there was plenty of stick travel left. After a few repetitions I finally thought to check the VNE chart... Realized THAT'S what retreating blade stall feels like in an R22... ( Tim Tucker at Robinson always said retreating blade stall at sea level is 150 in an R22... And I mostly fly at sea level... So it took a while to connect the temperature and altitude to the fact that I was flying way too fast.)
Finally coming out of White Plaines ( just north of New York City) IFR in the B206L3 I fly ( probably in the late 90s?) IFR, ATC climbed me to 12 for a little while before turning me east and letting me descend... But I was IMC so I don't remember anything unusual except the hands on the altimeter looking a little strange... ( and that it took a while to climb that high... I was heavy with fuel ).
The only time I found it really disturbing was that first time... The horizon was in an unusual position on the windshield, and I remember that my attitude flying sucked. No attitude indicators in R22s in those days, so that made it a little more... challenging to keep the machine level.
I guess that's pretty pathetic compared to VF!
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I surveyed (bird towing) the top of the Chilean Andes from Copiapo Chile to North of Antofagasta from West to East to the border of Argentina and back everyday for almost 4 months (time off in between) Did that with a B205 -17 and regular blades (single hyd) the everage fuel burn at close to sea level is about 610 to 615 lbs an hour, Le whole job was done at between 20,000 to 25,000ft DA and the average fuel burn at that altitude was about 400 to 415 lbs an hrs. I know the maximum altitude 204 blades will go to, but the T53-17 would have had no problems going higher.
JD
JD
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As an experienced rotary operator, I offer my thoughts.
Jet engines become more efficient as height increases (at least in the height band in which we operate), but rotors become less efficient. So the optimum operating altitude in still air will be different for every engine/rotor combination.
The expression 'in still air' is very significant, in my opinion. The greatest factor in efficiency is, by far, wind velocity. Go high when there is a tail wind component, and low when there is a head wind component. The choice of height in the tail wind option will depend on wind velocities at height, rather then engine/rotor efficiencies.
Jet engines become more efficient as height increases (at least in the height band in which we operate), but rotors become less efficient. So the optimum operating altitude in still air will be different for every engine/rotor combination.
The expression 'in still air' is very significant, in my opinion. The greatest factor in efficiency is, by far, wind velocity. Go high when there is a tail wind component, and low when there is a head wind component. The choice of height in the tail wind option will depend on wind velocities at height, rather then engine/rotor efficiencies.
