Posts about: "Dakar" [Posts: 4 Pages: 1]

ChristiaanJ
22nd Aug 2010, 21:04
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Post: 73
Quote:
Originally Posted by Nick Thomas View Post
I have yet another couple of questions and I hope all you Concorde experts don't mind me taking up your valuable time.
In my case, my time is no longer THAT valuable, being retired for several years !
And I enjoy answering those questions, if and whenever I can!
Quote:
As regards fuel burn: was there any difference between each indvidual airframe and if so was it significant enough to be considered when calculating the trip fuel?
There WERE differences... after its misadventure at Dakar, F-BVFD definitely consumed more fuel, although IIRC he was already reputed as a gas guzzler even before that incident.
It was one reason why, when Air France withdrew an aircraft from service, Fox Delta was the first one to go.
Also, due to the gradual improvements in production methods, and minor redesign, the last British production Concorde, G-BOAF, was about a ton lighter than the first one (G-BOAC). While the differences weren't huge, they were noticeable.
Quote:
Also did different engines also have slightly different fuel consumption?
Of course... but there I have no figures at all, and I doubt the differences, evened out over four engines, were really significant.
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Whilst on the subject of engines, I just wondered how many were required to keep the BA Concorde fleet flying? What sort of useful life could be expected from the engines?
Interesting question, and I hope somebody will come in and answer it.
According to 'Wikipedia', 67 engines were built, which would mean, in theory , 64 engines for 16 aircraft and 3 spares....
In practice, of course, fewer aircraft flew at any one time, so the statistics are different, but even so, a lot of engine swapping went on over the years.
As to the MTBO, I don't know... it's not my field at all....
stilton
22nd Aug 2010, 22:15
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Post: 75
Christiaan J


What happened to the Concorde at Dakar ?

Last edited by stilton; 23rd Aug 2010 at 04:58 .
ChristiaanJ
22nd Aug 2010, 22:54
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Post: 76
Quote:
Originally Posted by stilton View Post
What happened to the Concorde at Dakar ?
The story has never been fully elucidated....
But in brief, F-BVFD made an extremely hard landing at Dakar in November 1977, with a vertical speed in the order of 14 ft/sec (with 10 ft/sec being the formal limit).
The result was a major tailstrike, ruining the tail wheel and some of the tail structure.
The aircraft was repaired, repatriated, and put back into service, but it was the first one to be withdrawn from service when the Paris-Dakar-Rio route was closed.

In the end it was scrapped in 1994... only a section of the forward fuselage still remains in the stores of the Air and Space Museum at Le Bourget (Paris).
pattern_is_full
15th Jun 2015, 21:44
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Post: 1898
@ BN2A

I'm sure the real experts will "adjust" my understanding - but I believe Concorde, loaded for the transatlantic "Sierra" routes, could hit about 5000 fpm peak VS when climbing at 400 KIAS between ~10,000 and ~28,000 feet (wherever 400 KIAS = M 0.99). Leaving a coastal airport (New York, Barbados, Dakar), she would quickly be clear of land and could more or less transition directly through Mach 1 as soon as she reached 28-30,000 feet.

Those 4 Olympus engines could maintain Mach 2 with no afterburner at 50,000+ feet, so they had tons of excess power down low. Again my understanding is that they stayed at 100% dry thrust from brake release until TOD (except for subsonic cruise segments), with the AB added for takeoff, and when accelerating from Mach 0.96 through Mach 1.7.

Mach 2.00 was reached in about 30 minutes @ ~51,300 feet, depending on atmospherics - a relatively long slow slog compared to the initial climb and acceleration.

From inland airports such PDG or Heathrow, there was a "pause" for level subsonic cruise (M 0.94-0.96) in the high 20s until clear of the coastline by 20 miles (over La Manche or the mouth of the Bristol Channel.)

@ leb001 - greenhouse visor, BA livery, and short tail - probably G-AXDN (aircraft 101). Although I'll defer to the experts, as always.