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Ever heard of FOD? Foreign Object Debris.

Scroll to the bottom of this page to see the piece of metal that took down the Concorde.

In case that's too hard, here's the picture. According to Wikipedia, it was 435 millimetres (17.1 in) long, 29 to 34 millimetres (1.1 to 1.3 in) wide and about 1.4 millimetres (0.055 in) thick. There are parts on civilian drones much larger than that.

So if that was a drone that bounced off the nose, there could be pieces littering the runway large enough to take down a jet.

Ever heard of FOD? Foreign Object Debris.

Scroll to the bottom of this page to see the piece of metal that took down the Concorde.

In case that's too hard, here's the picture. According to Wikipedia, it was 435 millimetres (17.1 in) long, 29 to 34 millimetres (1.1 to 1.3 in) wide and about 1.4 millimetres (0.055 in) thick. There are parts on civilian drones much larger than that.

So if that was a drone that bounced off the nose, there could be pieces littering the runway large enough to take down a jet.

This and the fact that you also need to get a valid airworthiness certificate from the local authorities for it to fly. Getting that without OEM support is not impossible, it's just improbable for this aircraft. We keep WWII aircraft flying with one off machined parts all the time, but those parts are not difficult to machine by a modern shop. The materials used are common and the older manufacturing techniques aren't cutting edge anymore. Those older aircraft also tend to have much more simple control mechanisms (Concorde was a primitive partial fly by wire system). You would end up scouring collectors and museums for spares, not to mention corralling certified maintenance techs to work it.

Then we get to the engines, they'll need to be rebuilt and eventually be rebladed. There are enough surplus parts to keep the J79s from the 60's going, but there were thousands of those built. The Olympus 593s were a one off just for the Concord, not a lot of surplus parts floating around. Manufacturing new blades would be incredibly cost prohibitive.

My personal belief, if they want to throw billions into it, the best they'll be able to do is static runs and taxi displays. I don't think they'll get it into the air again and certainly not carrying passengers. I just don't think they have the muster to get a full D check completed and any local authorities to authorize it.

A good write up on what it would take. Impossible, no, improbable, yes.

One of the main problems with Concorde was It didnt have the range to do transpacific routes, and its not permitted to go supersonic over most countries.

Only 20 were ever built, which made even simple upgrades very expensive.

For example, the cost of the reinforced cockpit regulation brought about by 9/11 was relatively easy to absorb across thousands of Boeings.

The only important reason it failed is because it was incredibly impractical and expensive to operate. Yes it was a marvel and all that, but you couldn't make money off it.

My understanding is that Concorde's unprofitability was mostly myth. There were problems in the beginning because fear-mongering in the States left only JFK as a destination, but once things settled and the ticket prices were reset to ultra-high class, things settled out just fine.

Had the Concorde really not been profitable, it would have been terminated long before the crash over Paris. That's just how business works. The problem was simply that the planes were aging, no replacement models were being made, and the operators were left to scavenging parts from other Concordes. With the Paris disaster, they had more expenses reinforcing the fuel tanks to try and prevent the disaster from occurring again. These things ultimately tipped the scales to grounding the program.

But is there a demand for crossing the Atlantic in 3 hours? Is there demand to cross the Pacific in 5 or less? Hell yes. If they build it, people will pay the ticket price (and enjoy the view of the curvature of the Earth through the window).

The supersonic transport design dates from the early 1960s. The only reason it was delayed until 1976 was squabbling and lack of money. Do try to keep up.

Really? Where do you park it?

Pre-September 11 2001, Concorde almost consistently made operating profit on every flight. The aircraft only had to be half full to break even on all costs, INCLUDING FUEL.

(Source)

"You have to remember the intake flow to one of these engines is traveling at or near supersonic speeds."

The shape of the F-16 intake decelerates supersonic intake air to subsonic so it won't destroy the engine.

Fighter intakes

http://www.aircraftresourcecenter.com/AWA1/101-200/walk133_F4F_phantom/images/Mvc-0049.jpg

and those on the now-defunct Concorde

http://www.concordesst.com/powerplant.html

often used variable ramps to handle the problem. The F-16 does it without moving parts, quite an accomplishment at the time.

It was said to have no commercial future, but in the twilight of its flying life Concorde has emerged as one of the biggest money-spinners for British Airways, earning the airline as much as £50m in the past six months. In Concordeâ(TM)s final week alone BA is thought to have made about £6m in profit as customers vied for the cachet of being on board one of the last scheduled flights to travel through the sound barrier. . .

http://www.cronaca.com/archives/001605.html

In March 1984 the government ended its involvement with Concorde when British Airways assumed full responsibility for Concorde support costs. British Airways Board paid GBP16.5 million to acquire the government's stock of spare parts and was released from the profit share scheme under which the government collected 80 per cent of Concorde operating surpluses.

http://www.britishairways.com/concorde/faq.html

How much profit did Concorde make for British Airways? On average Concorde made and operating profit of £30-50 Million a year for British Airways in the boom years where many passengers were travelling first class. British Airways reportedly received £1.75 Billion in revenue for Concorde services against an operating cost of around £1 Billion. Air France made a much smaller profit.

http://www.concordesst.com/retire/faq_r.html

If you want actual financial figures, BA detailed Concorde as a seperate operating centre in its financial reports up until Concorde was retired.

Your claim that the Paris crash was caused by weight and balance issues and/or Air France's negligence is preposterous and patently false. Please, at least read the damn accident report before posting such misleading drivel.
Here the official summary, verbatim:
During takeoff from runway 26 right at Roissy Charles de Gaulle Airport, shortly before rotation, the front right tyre (tyre No 2) of the left landing gear ran over a strip of metal, which had fallen from another aircraft, and was damaged. Debris was thrown against the wing structure leading to a rupture of tank 5. A major fire, fuelled by the leak, broke out almost immediately under the left wing. Problems appeared shortly afterwards on engine 2 and for a brief period on engine 1. The aircraft took off. The crew shut down engine 2, then only operating at near idle power, following an engine fire alarm. They noticed that the landing gear would not retract. The aircraft flew for around a minute at a speed of 200 kt and at a radio altitude of 200 feet, but was unable to gain height or speed. Engine 1 then lost thrust, the aircraft's angle of attack and bank increased sharply. The thrust on engines 3 and 4 fell suddenly. The aircraft crashed onto a hotel.
You can find the report and supporting documents here: http://www.concordesst.com/accident/report.html
IAAP

Your claim that the Paris crash was caused by weight and balance issues and/or Air France's negligence is preposterous and patently false. Please, at least read the damn accident report before posting such misleading drivel.

Here the official summary, verbatim:
During takeoff from runway 26 right at Roissy Charles de Gaulle Airport, shortly before rotation, the front right tyre (tyre No 2) of the left landing gear ran over a strip of metal, which had fallen from another aircraft, and was damaged. Debris was thrown against the wing structure leading to a rupture of tank 5. A major fire, fuelled by the leak, broke out almost immediately under the left wing. Problems appeared shortly afterwards on engine 2 and for a brief period on engine 1. The aircraft took off. The crew shut down engine 2, then only operating at near idle power, following an engine fire alarm. They noticed that the landing gear would not retract. The aircraft flew for around a minute at a speed of 200 kt and at a radio altitude of 200 feet, but was unable to gain height or speed. Engine 1 then lost thrust, the aircraft's angle of attack and bank increased sharply. The thrust on engines 3 and 4 fell suddenly. The aircraft crashed onto a hotel.
You can find the report and supporting documents here: http://www.concordesst.com/accident/report.html
IAAP

One of my wife's relatives was a wind tunnel engineer on Concorde. I also remember seeing an interview with one the senior engineers on Concorde. He pointed out that Concorde was the FIRST in a projected series of supersonic transport aircraft. They had got over all the hard questions [propulsion issues, airframe heating etc. to name many] with Concorde and it would have been possible to scale up the design to larger sizes, assuming the propulsion improvements and efficiences could be developed as well. Concorde B was already being considered early on. Note the 10db reduction in takeoff noise.

After all, if you look at normal transport aircraft [Boeing & Airbus] they have got progressively larger and larger with more powerful but also more fuel efficient engines.

. That is what has brought the cost of air travel so low. As time passes and Concorde recedes more into the distance, I think it will be seen more and more as a missed opportunity.

That's because it used an afterburner to fly through the atmosphere like a fighter jet.

Actually, it didn't. The afterburners were only used on takeoff, and during the accelleration from Mach 1 to about 1.7. For the second part, afterburning wasn't strictly necessary, but turned out to be more efficient than accelleration on dry thrust.
Can't find good data on required runway length, but Concorde typically took off at 400 km/h, which is rather high. Accelleration from dry thrust may not have been enough to achieve 400 km/h on a typical runway.

IOW, people who refer to the F-22's supercruise ability as something new or unique, are wrong. Concorde could do this. (So could the English Electric P.1, prototype for the EE Lightning, by the way).

Here is an article about the concorde retiring

EXCERT
"The airline said that its decision had been made for commercial reasons with passenger revenue falling steadily against a backdrop of rising maintenance costs for the aircraft.
Detailed discussions over an extended period with Airbus, the aircraft's manufacturer, confirmed the need for an enhanced maintenance programme in the coming years, the carrier added.
British Airways has decided that such an investment cannot be justified in the face of falling revenue caused by a global downturn in demand for all forms of premium travel in the airline industry.
The downturn has had a negative impact on Concorde bookings and is set to continue for the foreseeable future, according to the airline."

Had.

So I take it the pictures of British streets strewn with shattered glass during the Concorde's high speed trials are just figments of the worlds collective imagination?

According to this source, the overpressure of the Concorde was about 16 pounds per sqare foot (PSF), or a little more that 0.1 psi. This level "will not cause material damage to any structure in a reasonable state of repair", subject to their definitions of material damage and reasonable state of repair. That level of overpressure, combined the short-duration square-wave nature of the pressure signal tend to make the impact somewhat more significant than the 30-mph (50 kph) wind they compare it to. It also doesn't account for the presence of other factors, ie: a window that is already stressed by a 30 mph wind will shatter more easily than a window that is not stressed.

Finally, there were designs on the drawing board for an American SST, but Congress pulled to funding. And the real money (particularly now) for airlines has been on international routes because various bi-lateral agreements limit capacity and city-pairs, driving up fares. Domestically, the mid-course speed benefits of an SST are mitigated by the more fixed-speed ground and departure/approach legs of the flight (fly United and listen in on the ATC comms, flying into San Francisco you might hear orders to reduce speed for 'traffic flow' somewhere over Utah).

As for cost, I guess we'll have to agree to disagree. You believe that there is a market for high-speed flights that cost several times more than regular flights. I do not.

How many customers have travelled on Concorde?
More than 2.5 million since it started commercial passenger services in 1976. *

I never said that the Concorde program was a success. However I feel a 20+% more efferent plane with a longer range could be vary successful. A new project needs to keep R&D costs low but "British Airways reportedly received £1.75 Billion in revenue for Concorde services against an operating cost of around £1 Billion." which is not bad for a single market and with more markets you end up with a lower R&D cost per flight. Air France made a much smaller profit, but only 14 entered airline service so a program that creates 50 Jet's with lower operating costs seems like a good idea to me.

It's going to be vary risky, but there is value in large projects like these. Once you become the only company that can make such a product you get to feed off of that market for a long time. You look at it as an open market where your competition sees a viable competitor, which prevents most competition yet governments see plenty of direct competition via normal Jet's so they are not going to try and break you up.

* http://www.concordesst.com/retire/faq_r.html

I remember one of the curious aspects of Concorde was that fuel management was extremely important. On the LHR to/from IAD runs you only had 15 seconds of afterburner on takeoff and 30 seconds on the sub to supersonic transition.

The Braniff pilots (you remember Braniff don't you) who flew Speedbird to/from IAD/DFW didn't get to go supersonic over the continental US so they got to sit on the afterburner on takeoff longer.

They always were a bunch of cowboys ;-)

Yeah and British Airways refusing to sell him Concorde was really really annoying. I would have loved to have had him keep it flying.

Except that, like many things with Branson, that was all PR and not a real desire on his part.

Sad, but true. At some stage in the late 1960s, when costs of developing Concorde were spiralling out of control, the UK government effectively took a 49% share to the French govt's 51% share. This meant that the French were the Design Authority. After the accident at Paris, and despite the reworking of the fuel tanks by British Aerospace and Aerospatiale, Air France ( = the French Government) lost faith in the aircraft, probably because ticket sales never recovered the way they did for British Airways. Hence, Aerospatiale, as the Design Authority, announced the intention to cease to provide DA status. Without DA, there can be no Certificate of Airworthiness. If the UK had been the DA, then it is possible that BA would have kept it going, as, with all the development costs written off back in the early 1970s, it was actually making an operating profit for them.

Supersonic jets using afterburners use ungodly amounts of fuel.

correct, but the Concorde didn't ordinarily use afterburners; it had them only for the greater thrust demands at take-off and during acceleration, not for cruise. it was an expensive plane to run largely because of its low seating capacity and short range, which barred it from many of the lucrative trans-Pacific routes.

(some have also argued that the low-to-nil bypass ratio of the Concorde's Olympus engines made it more expensive to run. that may be true; i don't have any really convincing evidence either way.)

I've heard the Concorde made slightly less noise than a 747-400 or something like that.

that would have had to depend on what the plane was doing. during landing, i can well believe the difference might have been small; during take-off (under afterburners, natch!) that would very much surprise me; and while supersonic, absolutely not.

Concordes were politically acceptable so long as they stayed subsonic over land, so nobody would complain about the boom. they were also hideously expensive to run, which in a more rational world might have shut them down all by itself, but apparently there were enough eccentric ultra-rich people to keep them flying for decades in spite of that fault. no amount of money, however, would let them reamin at their designed cruise speed above anyplace people lived, and that was as much a political shortcoming as a technical one.

Supersonic jets using afterburners use ungodly amounts of fuel.

correct, but the Concorde didn't ordinarily use afterburners; it had them only for the greater thrust demands at take-off and during acceleration, not for cruise. it was an expensive plane to run largely because of its low seating capacity and short range, which barred it from many of the lucrative trans-Pacific routes.

(some have also argued that the low-to-nil bypass ratio of the Concorde's Olympus engines made it more expensive to run. that may be true; i don't have any really convincing evidence either way.)

I've heard the Concorde made slightly less noise than a 747-400 or something like that.

that would have had to depend on what the plane was doing. during landing, i can well believe the difference might have been small; during take-off (under afterburners, natch!) that would very much surprise me; and while supersonic, absolutely not.

Concordes were politically acceptable so long as they stayed subsonic over land, so nobody would complain about the boom. they were also hideously expensive to run, which in a more rational world might have shut them down all by itself, but apparently there were enough eccentric ultra-rich people to keep them flying for decades in spite of that fault. no amount of money, however, would let them reamin at their designed cruise speed above anyplace people lived, and that was as much a political shortcoming as a technical one.

Supersonic jets using afterburners use ungodly amounts of fuel.

correct, but the Concorde didn't ordinarily use afterburners; it had them only for the greater thrust demands at take-off and during acceleration, not for cruise. it was an expensive plane to run largely because of its low seating capacity and short range, which barred it from many of the lucrative trans-Pacific routes.

(some have also argued that the low-to-nil bypass ratio of the Concorde's Olympus engines made it more expensive to run. that may be true; i don't have any really convincing evidence either way.)

I've heard the Concorde made slightly less noise than a 747-400 or something like that.

that would have had to depend on what the plane was doing. during landing, i can well believe the difference might have been small; during take-off (under afterburners, natch!) that would very much surprise me; and while supersonic, absolutely not.

Concordes were politically acceptable so long as they stayed subsonic over land, so nobody would complain about the boom. they were also hideously expensive to run, which in a more rational world might have shut them down all by itself, but apparently there were enough eccentric ultra-rich people to keep them flying for decades in spite of that fault. no amount of money, however, would let them reamin at their designed cruise speed above anyplace people lived, and that was as much a political shortcoming as a technical one.

See Concord, July 25, 2000.

The Concorde wing is static, except for the obvious movable control surfaces. Does not change shape in flight.

But only after using the afterburner to get there.
The reheats are turned back on, by the piano switches behind the thrust leavers, for around 10 minutes once the aircraft is clear of land, to push the aircraft through Mach1 and on to Mach1.7 where they are no longer required.

The F-22 can exceed M1 withuot any afterburner use at all.

"The space agency's dogged pursuit of extreme speed, officials hope, will ultimately make space flight easier to accomplish.

It also could drastically cut the time of commercial flights -- perhaps shortening the trip between New York and London to less than five hours."

What the fuck? There is not and never has been any aircraft manufacturer with a name close to "Aerospaciale." The Concorde was jointly developed by a consortium of British and French companies, none of which have the name which you conjured.

Even if they'd had good reception from the carriers, that wouldn't have guanteed success. Concorde had good reception from the carriers, with 18 different airlines actually placing orders or options. Unfortunatly between the start of the project and the aircraft being available for delivery, the world changed, in particular the success of wide-bodies and with PanAm and TWA cancelling their orders, the fate was sealed - without the two biggest american carriers at the time, they couldn't get any other carrier to commit. Ever since then, aircraft manufacturers have required substantial interests from carriers before committing the money involved in creating a new modern jetliner.

Erm, I think you'll find the Rolls Royce Olympus engine is a turbojet, not a ramjet.

Concorde Powerplant page.

P.S. There's an 'e' on the end of Concorde as well - it's in French.

Concorde didn't use its afterburners while cruising.

http://www.concordesst.com/powerplant.html

Perhaps you should think before you post?

Air France is donating one of is Concorde's to the Smithsonian

Several people have suggested that there are many aircraft (miltary and civilian) that rival the Concordes ability to fly at a sustained mach 2 for several hours. However, according to this site www.sr-71.org it is only Concorde and the SR-71 which can do this. I know there are aircraft faster, more efficient etc thats not the point. This is still beyond the performance of all civillian aircraft and virtual all military aircraft. Further, a sustained high speed must be a most desirable characteristic of any passenger aircraft. (It does not take Concorde 2 hours to reach this speed either concordesst). Bottom line, we want aircraft to get us there quick, and concorde is the quickest.

It could have got a lot quieter if anyone had bought more of them. There were plans for a 'model B' in 1976 which would have added all sorts of improvements (including addressing the noise problems). They were struggling to sell the last of the 17 that they did build, so the new model just never happened.

For more details: http://www.concordesst.com/concordeb.html

Well, it's only almost perfect...

There's not so much difference between a registry and an /etc tree.

Both are a database of settings, the registry is powered by a more powerful searching and indexing engine and not wasting a full disk sector (or cluster) for "keys" only containing five bytes of data, that's all.

PS: "a full disk sector" is 512 bytes. You think of a filesystem block ("cluster" in FAT-speak). This would be 1-4k for ext2. And ReiserFS does pack short files, wasting far less than a block -- so your basic assumption is flawed.

Concorde's about mach 2 at cruise at 60,000 feet. : Performance Data.
I've been lucky enough to do a four hour flight from the Middle East on it and it's without a doubt the most incredible experience - travel faster than most fighter jets whilst sipping champagne.

It's an eternal shame that such advanced concepts and ideas seem to have gone to waste in Passenger Aviation.

In point of fact, Concorde is Anglo-french, a joint venture. Though it was indeed a french one that came down, as the British Airways ones had all been modified for that kind of problem to a degree previously.

- Chris

Take a look at the good old Concorde

So does the mighty USA Army, but we don't complain about that!

IMO, Concorde demonstrates the superiority of the European and Japanese practices of 'corporate welfare'. We need to get more of this in the USA, or else these more socialist countries will run rings around us technology-wise.

When the profit motive is the only force in the market, the inevitable result is stagnation and monopoly. The Socialist governments of France and the United Kingdom showed that two Socialist countries could achieve what even the greatest nation on earth could not: Supersonic passenger aircraft.

It is interesting to note that the only other supersonic airliner was the Tupolev TU-144 which came from that other Socialist utopia the USSR.

I am not saying the USA should become socialist, but it should recognize that to achive true greatness and kick-ass status, it needs to develop a supersonic airliner of its own, otherwise people will still look to Britain and France as the most advanced nations.

Come on, you can't tell me you don't feel a tinge of national humiliation every time you see the sleek sexy lines of the Concorde parked at JFK airport ?

Concorde can fly at mach 2.01. That's almost the mach 2.1 mentioned above, and it's a *commercial passenger airliner*. I find it rather hard to believe that the military aircraft in production don't go much faster! People need to get their facts straight before spouting off technical details and trying to sound clever.

http://www.concordesst.com/performance.html