Why don't jets fly higher?
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If BOAC had been allowed to charge normal fares in the first place, rather than being shafted by the rest, there would have been dozens more Concordes sold.
When a chap from BAC gave us a lecture at school in 1965(?), the brochures he brought to give to us spotty schoolboys had the aircraft displayed in ALL the logos of airlines who'd indicated a willingness to buy - and there were at least 20. The US SST saga (bigger, faster and too expensive) followed, along with 'SSTs cause cancer' or other such utter rubbish whipped up by american (small a, big @rse) tree-huggers and encouraged by sour grapes types in the US aerospace industry and media.
[This message has been edited by BEagle (edited 08 July 2000).]
When a chap from BAC gave us a lecture at school in 1965(?), the brochures he brought to give to us spotty schoolboys had the aircraft displayed in ALL the logos of airlines who'd indicated a willingness to buy - and there were at least 20. The US SST saga (bigger, faster and too expensive) followed, along with 'SSTs cause cancer' or other such utter rubbish whipped up by american (small a, big @rse) tree-huggers and encouraged by sour grapes types in the US aerospace industry and media.
[This message has been edited by BEagle (edited 08 July 2000).]
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Whilst all of what's been said is true, there is some more to it.
The FAA (if I remember correctly) report that subsonic "corporate" jets now cruise at up to 51000 feet.
I guess the main factor is engines. The power required to maintain higher altitudes is not cost effective for scheduled airlines.
The FAA (if I remember correctly) report that subsonic "corporate" jets now cruise at up to 51000 feet.
I guess the main factor is engines. The power required to maintain higher altitudes is not cost effective for scheduled airlines.
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Just to nail one common misconception - the Concorde fleet does indeed make a profit for BA. I believe that for two of the last eight quarters it was the only fleet to do so.
(Yes, I know this disregards acquisition costs, but of course they would anyhow have long been amortised on any fleet which had been in service for this amount of time).
(Yes, I know this disregards acquisition costs, but of course they would anyhow have long been amortised on any fleet which had been in service for this amount of time).
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ROADTRIP. You were way off the mark. Concorde is actually BAs most profittable fleet, A/C for A/C. It makes a lot of cash and breaks even across the pond with less than half its seats full.
The yanks killed supersonic flight because they couldn't do it. \the environmental impact od spaceflight is far greater but thats OK because they can do that!
The yanks killed supersonic flight because they couldn't do it. \the environmental impact od spaceflight is far greater but thats OK because they can do that!
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Back to the original topic, what you need is more thrust. Plenty of spare power will get you nice and high. Handley Page's finest bomber, the Victor could get to FL600 with no problems, I flew one of the Tanker versions with it's shorter span up to FL520, and we could cruise at M.9 at FL470. There was nothing to match us in those days, but you can find some GIVs and Citation Xs up there now.
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So - back to the question as you rightly point out - if GIVs and Citations can do it why have Airbus and Boeing elected not to? If they decide they want more power they just ask RR,GE etc, don't they?
Or put the question the other way round - if Airbus and Boeing don't think it's sensible what is the attraction to the corporate jet manufacturers?
Or put the question the other way round - if Airbus and Boeing don't think it's sensible what is the attraction to the corporate jet manufacturers?
Finding a couple of engines with XS power for a "light" corporate jet is no problem, and giving them F500 capability will get them direct routing.
For a commercial airliner, if you can find extra power, then you make more money by increasing the take-off weight of the aircraft to maximise revenue & range.
For a commercial airliner, if you can find extra power, then you make more money by increasing the take-off weight of the aircraft to maximise revenue & range.
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A few point on the original question.
The pressuredifferential between inside and outside the cabin is the main item. the aircon/pressurisation system will be able to maintain a reasonable (FAR/JAR certifiable that is) pressure diff. and the hull and windows can be designed to cope with it. Once an aircraft model has been designed for a certain pressure diff. it is not easy to increase it so you are faced with what the pressurisation system can do after modifications and also what the structure (incl. windows and doors) can stand.That's for the cabin area. As a large part of your fuel/hydraulics etc. systems run outside the pressure hull. this must also be able to cope with the increased pressure diff. (now greater from within the pipes/boxes to the outside of them).
Then also the engines as said before. A lot more puff needed in thinner air.
The whole lot then needs to be re-certified. Lots of work for the manufactutrer and the authorities.
In the end... Is it worth it is some case? Need a good market to get your money back. the Airlines will often not accept to pay much for it.
A is dum (Is A?)
The pressuredifferential between inside and outside the cabin is the main item. the aircon/pressurisation system will be able to maintain a reasonable (FAR/JAR certifiable that is) pressure diff. and the hull and windows can be designed to cope with it. Once an aircraft model has been designed for a certain pressure diff. it is not easy to increase it so you are faced with what the pressurisation system can do after modifications and also what the structure (incl. windows and doors) can stand.That's for the cabin area. As a large part of your fuel/hydraulics etc. systems run outside the pressure hull. this must also be able to cope with the increased pressure diff. (now greater from within the pipes/boxes to the outside of them).
Then also the engines as said before. A lot more puff needed in thinner air.
The whole lot then needs to be re-certified. Lots of work for the manufactutrer and the authorities.
In the end... Is it worth it is some case? Need a good market to get your money back. the Airlines will often not accept to pay much for it.
A is dum (Is A?)
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If Concorde is so economically successful, why aren't there more updated versions being built and being flown on more diverse routes? Granted, Concorde is held hostage in the never-ending Euro-US pissing contest. As far as making a profit goes - I'll bet the books wouldn't stand up to close scrutiny -- Maintaining a fleet of 8 very specialized aeroplanes has got to be even more costly than even gold-plated tickets allow. I would imagine that Concorde is kept in impeccable maintenance condition.
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There will never be another SST, not in our lifetime. This has probably been mentioned here before, maybe even by me, but when it takes 90 minutes to get from the west end of London to checkin, saving an hour or two on the flight times is not worth the extra cost. The average speed of traffic in London is slower than horse-and-cart Victorian times - it's 6 mph. Plus there are huge parts of the planet (the bits with people on) which are a no-go area for anything that generates a sonic boom. Planes piddle along at subsonic speed not because of restrictive gov'ts or whatever, but because the market for a profitable line of aircraft doesn't exist. There are few routes suitable and few passengers willing to pay the $$$ to save an hour or two. I wouldn't pay - is 5hrs45 en route NYC-LON so horrible that it's worth paying not £250 in economy on a 747 but maybe £1000 on a NG SST to fly the same distance in 3 hours? No, especially when you're not halving your journey time, but maybe cutting it by 15% (counting 90 minutes each end for ground transportation, 60 minutes check-in and 60 minutes baggage reclaim and customs / immigration) - journey times are 747: 10hrs45, SST 8hrs.
A SST biz jet would make slighly more sense.
A SST biz jet would make slighly more sense.
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I used to regularly cross the Atlantic on 747s, now I regularly cross in an SST. Believe me, the difference is enormous in contradiction of the above.
The reason that there will not be an airliner successor to the Conc is twofold: As already stated, the market will not support enough machines to make a viable manufacturing case. Secondly - the problem of noise in T/O and landing phases. Chapter 111 is barely achievable, 1V would be impossible.
I agree that the next civil SST will be a bizjet for both these reasons.
The reason that there will not be an airliner successor to the Conc is twofold: As already stated, the market will not support enough machines to make a viable manufacturing case. Secondly - the problem of noise in T/O and landing phases. Chapter 111 is barely achievable, 1V would be impossible.
I agree that the next civil SST will be a bizjet for both these reasons.
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Hey Roadtrip you realy do have a fly up your whatsit!
As previously mentioned, Concorde was embraced by an awful lot of US airlines in it's early days and made great economical sense. Just when two small countries bit the bullet and past the point of no financial return (based on all those airlines support), along comes Boeing. When the US realised their Mach 3 rival was going to bust the bank.... they said, 'Oh well, it aint possible, it's therefore impossible for anyone else.
Despite all the doubts, the tree hugging (a lot misplaced) and the finer politics of New York Port Authority, etc, the bird flew commercially for two and a half decades, and many American people enjoyed the experience too.
To date no other country large or small has operated a commercially sound aircraft across the oceans at the speed of Concorde other than France and UK ....
...and I guess thats the bit that hurts.
I suggest a book to read called Concorde and the Americans.
Me, I'm happy to cruise at 35,000 at any speeed, just so long as I don't have to try and enjoy sour grapes with my in flight meal.
[This message has been edited by buck-rogers (edited 25 October 2000).]
As previously mentioned, Concorde was embraced by an awful lot of US airlines in it's early days and made great economical sense. Just when two small countries bit the bullet and past the point of no financial return (based on all those airlines support), along comes Boeing. When the US realised their Mach 3 rival was going to bust the bank.... they said, 'Oh well, it aint possible, it's therefore impossible for anyone else.
Despite all the doubts, the tree hugging (a lot misplaced) and the finer politics of New York Port Authority, etc, the bird flew commercially for two and a half decades, and many American people enjoyed the experience too.
To date no other country large or small has operated a commercially sound aircraft across the oceans at the speed of Concorde other than France and UK ....
...and I guess thats the bit that hurts.
I suggest a book to read called Concorde and the Americans.
Me, I'm happy to cruise at 35,000 at any speeed, just so long as I don't have to try and enjoy sour grapes with my in flight meal.
[This message has been edited by buck-rogers (edited 25 October 2000).]
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I have flown the DC-8-62 at FL410, there was no problem with "coffin corner".
Handflew Learjets 24/25 routinely at FL450, I believe the margin is somewhere around 40kts. Flies nice at those altitudes. In testing I believe they did steep turns at those altitudes.
NASA used to fly their 23 to FL500, they also took a DC8 to 450 and did a highspeed dive attaining M 1.07. First supersonic tranport??
Handflew Learjets 24/25 routinely at FL450, I believe the margin is somewhere around 40kts. Flies nice at those altitudes. In testing I believe they did steep turns at those altitudes.
NASA used to fly their 23 to FL500, they also took a DC8 to 450 and did a highspeed dive attaining M 1.07. First supersonic tranport??