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Helicopter max climb altitude

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Helicopter max climb altitude

Old 31st Oct 2019, 09:14
  #21 (permalink)  
 
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Originally Posted by Agile View Post
can anybody provide some technical insight about the factor of high altitude flying in a helicopter,

any other factors?
In a turbine, you'll always be Ng limited so depending on helicopter type P2 bleed / heating not allowed if you're landing or taking off with max power etc.
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Old 31st Oct 2019, 13:53
  #22 (permalink)  
 
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Devil

Originally Posted by RINKER View Post
Hi vf I remember from my pplh about oxygen use at altitude.

sorry to ask a daft question but did you need to use oxygen at that altitude.

R

G'day R....depends on the countries regs? Usually above 10,000' You've gotta be sucking on O2 if there for over 30mins. Other countries same deal but starts at 14,000'. But also depends on Your Health, smoker, etc....seen many a Pilots get problems above 15,000' even on O2? Also depends on how acclimatioed You are.....when I was flying to 20,000'+ 2, 3 times a day, sleeping at 10,000' every night then landing at 18,000 'for fuel staging without O2 was easy with nil effects, even when I camped there (@18,000' due weather), drunk a half bottle of Ruksi that night & still no effect the next morning


If not acclimatised to high altitudes...I'd be donned O2 continuously operating above 10,000', if You're an asthmatic or a smoker then start sucking above 8,000'
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Old 31st Oct 2019, 14:11
  #23 (permalink)  
 
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Originally Posted by ApolloHeli View Post
In a turbine, you'll always be Ng limited so depending on helicopter type P2 bleed / heating not allowed if you're landing or taking off with max power etc.
Seriously.....Ng limited hmmmm not in any American build donks
Seriously.....P2 bleed dingle bits do NOT need to be off for take-off, nor landings, use is 'as required' with a caution that performance is degraded (singles that I fly)
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Old 31st Oct 2019, 14:20
  #24 (permalink)  

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Originally Posted by Vertical Freedom View Post
Seriously.....Ng limited hmmmm not in any American build donks
Seriously.....P2 bleed dingle bits do NOT need to be off for take-off, nor landings, use is 'as required' with a caution that performance is degraded (singles that I fly)
Agreed, Sometimes it's better to keep the airbleeds on, such as when flying in cold/humid conditions. The chance of the canopy misting up near the ground can be far more serious than losing a little power. I know of one fatal takeoff accident where canopy misting was the cause and another where it was a likely cause.
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Old 31st Oct 2019, 17:15
  #25 (permalink)  
 
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Unless you are gong to look at something that is 10,000ft. plus there seem little point of going that high.
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Old 31st Oct 2019, 19:57
  #26 (permalink)  
 
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Originally Posted by Fareastdriver View Post
Unless you are gong to look at something that is 10,000ft. plus there seem little point of going that high.
Well, photography of tall things can sometimes call for it. Back in the early 1980's I was hired to shoot photos for a book on Mexico's national parks and "natural wonders." My publisher wanted some shots of Volcan Popocateptl outside Mexico City, so in addition to the ground visit, we hired a Hughes 500 (if I remember right) and pilot out of Aeropuerto Benito Jurez.

It was a beautiful clear day, flying over to the volcano with the door removed on my side. To get a good angle on the volcano, the pilot kept climbing higher as we slowly circled it. The mountain is 17,802 ft. high. I wasn't paying attention to the gauges but I know we didn't get high enough to see into the caldera, so I'd estimate we reached maybe 14,000-15,000 feet. I remember at one point the pilot said we had set a local altitude record for helicopters. That surprised me; I didn't think we were up that high. The ground looks abstract and difficult to judge height once you get high enough. I do remember how cold it got. I hadn't thought ahead about what it would be like with the door off at that altitude, and wasn't dressed for it. Lesson learned for later air-photo flights in mountainous areas.

I don't remember any ill effects from the altitude. We weren't up there for more than a few minutes, and I had been staying for a couple of weeks in a hotel in Mexico City at 7,000 ft. I guess I was partially acclimated, and so was the pilot working out of that airport.
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Old 31st Oct 2019, 20:28
  #27 (permalink)  
 
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I was thinking about 10,000ft. AGL.
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Old 31st Oct 2019, 20:37
  #28 (permalink)  
 
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Max Altitude

Fascinating reading!

"...... Because of the ice and clouds, the test pilot had no outside visibility. Attitude instruments had been removed to lighten the helicopter. Boulet looked up through the canopy at the light spot in the clouds created by the sun, and used that for his only visual reference until he broke out of the clouds......"

https://www.thisdayinaviation.com/21-june-1972/

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Old 31st Oct 2019, 21:58
  #29 (permalink)  
 
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The highest I’ve been to in a helicopter (Bell407) was up to FL110 for a photo mission. Didn’t like it
Once flew a Jetranger at 10,000', doors off. Didn't like it either, especially when encountering some light turbulence.
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Old 31st Oct 2019, 22:09
  #30 (permalink)  
 
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I've been up at 15,000' in a S-92 and a Blackhawk for flight testing. I can tell you the S-92 does not like to do an engine restart at 15,000'. We ended up descending to 13,000' where it did restart.
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Old 31st Oct 2019, 22:12
  #31 (permalink)  
 
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Some great reads here. What about Link Luckett and his Hiller 12E.... I remember that as a kid. Will have to research a bit...
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Old 31st Oct 2019, 23:42
  #32 (permalink)  

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Originally Posted by Fareastdriver View Post
Unless you are gong to look at something that is 10,000ft. plus there seem little point of going that high.
We were looking to see if mountain goats really did live in the clouds.
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Old 1st Nov 2019, 10:54
  #33 (permalink)  
 
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Been to the very top of the Matterhorn (14,692 feet) in an AS350 (Air Zermatt). Brilliant blue skies and the machine handled it easily.
Unfortunately staying in the village for several days did my head in (migraines).
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Old 2nd Nov 2019, 07:08
  #34 (permalink)  
 
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Unless you are gong to look at something that is 10,000ft. plus there seem little point of going that high
Doing the first turbine endorsement (Huey) one exercise was attempting to get into vortex ring at 14,000, never did, but had to wear parachute for anything over 5,000. Training in the USN oxygen was required above 10,000 day and 5,000 night. FW instrument flying training was done between 10 and 20,000, never used oxygen as found the mask so uncomfortable, never had a problem, 20YO and fit I guess. Some of the US Army chaps I flew with in country had a fear of anything above 1,500 because of MGB failure worries, took one such lad to 16,000 in a Huey trying to quell his fears. Regularly flew IMC at 10,000 on transits in 212, 412, 76, LSALT in our area being 6,000 though airport at each end being at sea level.
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Old 2nd Nov 2019, 14:58
  #35 (permalink)  
 
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Originally Posted by Fareastdriver View Post
Unless you are gong to look at something that is 10,000ft. plus there seem little point of going that high.
Having spent a bit of time on filming jobs at 10k+ AGL in helicopters, I disagree.
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Old 2nd Nov 2019, 15:37
  #36 (permalink)  
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Namaste VF

I keep looking at the threads for your contribution, glad to hear you are well, can you give us a clue as to your whereabouts and what you are up to?
Missing the sleek trim photographs of.........helicopters, hope Mrs VF is well.

Regards,
T18
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Old 4th Nov 2019, 09:52
  #37 (permalink)  
 
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Originally Posted by nomorehelosforme View Post


Repos,

That was an interesting story to read after a hard days work Thanks for posting!
Interesting is one way of putting it. Another way might be hard to actually believe. Reckons he was in the air for an hour and a half after leaving with 25% fuel? Id need to see better evidence than that piece of writing.
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Old 4th Nov 2019, 10:12
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Originally Posted by rottenjohn View Post
Interesting is one way of putting it. Another way might be hard to actually believe. Reckons he was in the air for an hour and a half after leaving with 25% fuel? Id need to see better evidence than that piece of writing.
It does seem a bit contradictory unless there is a dramatic reduction in fuel burn with altitude to compensate. Looks like about 180 l/hr is average cruise consumption, so to stretch 132 litres to 1:35 (albeit with about 10+ min in autorotation), looks like a tall order. That said, I flew one type where with full fuel you had about 3 hours endurance at sea level in the cruise, but climbing to 10,000 ft the endurance was now 3:25 even after the climb fuel consumption (fuel burn dropped from 320 kg/hr to 275 kg/hr), so I'm not sure how much lower the consumption would have continued to reduce if we'd climbed higher.
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Old 4th Nov 2019, 12:34
  #39 (permalink)  
 
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Originally Posted by rottenjohn View Post
Interesting is one way of putting it. Another way might be hard to actually believe. Reckons he was in the air for an hour and a half after leaving with 25% fuel? Id need to see better evidence than that piece of writing.
I guess fuel burn reduces with altitude...note to self; I wonder why airliners fly so high

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Old 4th Nov 2019, 12:39
  #40 (permalink)  
 
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Originally Posted by 212man View Post
It does seem a bit contradictory unless there is a dramatic reduction in fuel burn with altitude to compensate. Looks like about 180 l/hr is average cruise consumption, so to stretch 132 litres to 1:35 (albeit with about 10+ min in autorotation), looks like a tall order. That said, I flew one type where with full fuel you had about 3 hours endurance at sea level in the cruise, but climbing to 10,000 ft the endurance was now 3:25 even after the climb fuel consumption (fuel burn dropped from 320 kg/hr to 275 kg/hr), so I'm not sure how much lower the consumption would have continued to reduce if we'd climbed higher.
In a B3+ & e I was sucking ~90lph above 20,000' & 70lph @ 28,000' hmmmmm given 540litres usable petrol tank @ 25% = 135litres (not 132, every drop counts at extreme alt.) so way more than 2hrs of noise time at those scary heights is very achievable in a B2 fuel burn even less...so what part is hard to believe again??

rehash; wonder why airlines soar up to 35,000' surely not just for the view

Keeping it real....do it into wind whenever possible (except pea)

Last edited by Vertical Freedom; 4th Nov 2019 at 13:08.
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