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Discussion Starter #1
I thought you might know this being our resident aviation expert. We were flying back from Ibiza last Sunday evening at 37000 feet, flying over NW France i looked out of the window and saw the vapour trail of a plane above and i reckon it was at least 70000 feet above us, any idea what it was, a military reconnaisance aircraft?.
 
G

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Difficult

Most civvy jets can get to the altitude with provisos.

Max altitude for a B747 is 45,100' for example. The aircraft has to be nearly empty to get there though. 41,000' is typically achievable at the end of a long flight once the fuel is burnt off. With modern engines the engines can get there, but the wings can't, so we watch the weight and when enough fuel is burn't off we ask for higher (normally in 2,000' steps). However, what normally happens ATC hold you down as they have enough problems controlling aircraft laterally as well as vertically.

So, it must have been a bizz jet ;as these can get to altitude almost immediately after take-off. Aicraft such as the Gulfstream - Falcons. Or it could have been a French fighter, but fighters normally haven't got the fuel to sustain cruise without a tanker. :D

Other, possibilities are USAF - bombers - B1 - B2 - B52 - all unlikely as there's no requirement for them to fly over France.

OT

Years ago the Concorde fleet flew more hours than ALL the worlds military aircraft supersonically put together. I don't know what the ratio is now I should say at least 10 times more.

Doesn't really answer the question though!:xxrofl:
 

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Discussion Starter #3
I see, i was under the impression that all commercial aircraft flew at between 30-40000 feet, obviously not but why fly at 100000 feet, not so busy up there i suppose!.
 
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Kevin

4 - engined - KC135 - B52 - Boeing 747 - Airbus A340.

100,000' - the hull would have to be so thick to sustain the pressure difference to maintain an equivalent altitude of 8,000' or you would need to be on Oxygen.

You will then say what about concorde, I don't know what equivalent altituude that rit uns at - buty it flys at circa 56,000.' I think it may 10,000 and around 9psi diff. I could find out.

During the days of the mighty V[-force/B] and high level bombing was the genre, they flew at 50,000' with pressure breathing suits in the Vulcan & Victor.

You are right the higher the better for fuel economy and range. There's always a compromise. We always climb whenever possible to normally 37,000.' As you say commercial jets rarely get above 40,000 - but we can! I wopuld suspect it was a jet on delivery, military arcraft, an airtest (manufaturer checking the aircraft) or a empty aircraft.

Don't know if you are aware but frequent flyers (aicrew) are monitored for hours spent in the cruise (Radiation issues). But you have to fly many hours above 35,000' for it to be a concern. ot a problem.

Another one is flying pax. If the hull ruptures at 30,000' you haven't got long before you "kick it" or you wear the drop down Oxygen. This is why they get you down to 14,000' ASAP. Flying freight we don't bother much, as we know we can get the mask on.
 

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Discussion Starter #6
Jerry,
We were in an Airbus 300B, the wide one,belonging to Monarch, i reckon it was getting on a bit, anyway it was making lots of odd noises especially when the under carriage went up and down and the flaps moved but i always look at the trolley dollies in these situations, if they don't look worried then the plane does it all the time. I would be very worried if i sat on a plane and John Lithgow was sat by the window next to me!!! (do you know the film?).
 

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CONCORDE

Watching a programe regarding Concorde, can't remember what it was. Could have been something to do with the Speed of Sound and the "bang". Miles were the leaders in this field during the War but had the project taken off them and it was given to the Americans. Not sure if the Government of the day had their hands tied or the American's stuffed us. Anyway it was thought the Brits had about 2/3 years advance over the Russians and the Americans.

Wondering off the subject on to the subject. Concorde grows about a foot when reaching its max ceiling. Quite incrediable.

Jim
 

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Isn't it something to do with the heat generated making it expand. Clarkson was on in the week disussing the SR-71 Blackbird and it expands so much that until the thing is up to altitude and temperature, the fuel tanks actually leak :eek:
 
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