Posts about: "Air France 4590" [Posts: 42 Pages: 3]

Well I have to say this is a brilliant thread.

I stumbled upon it by accident and been catching up on it when I had a spare moment and have found it completely riveting and it has whiled away many hours over the past month.

I\x92m ex-RAF and spent the last ten years working as an engine bloke on the T aeroplane & RB199. We were always told there were many parallels with Concorde & the Olympus 593 \x96 TBT/T7 Gauges, Optical Pyrometers, EPC Coils on-engine FCU\x92s, Vapour Core Pump for reheat fuel as well and the like. I attended the RR Manufactures course for two weeks at the Patchway Works and spent a day at the Concorde Museum seeing the similarities with the Electronic Control Units too though Lucas Aerospace made the MECU\x92s or GR1/4 (& DECU\x92s on the F3\x92s).

Also while on the course the distinguished RR Instructor Gent filled up in with various snippets of Engine History too such as the Vaporisers which were fitted to RB199 & the later models of Olympus 593 were originally Armstrong Sidderly designed for the Sapphire, also I learned the whole 15 Stage Sapphire Compressor was lifted completely and fitted to later Avon\x92s as it worked better.

I was at Leuchars in the early 80\x92s and the Open Golf peeps all arrived in one of these magnificent lady\x92s \x96 the visit was notable for several things; someone fired off an escape chute!!! \x96 What does this little handle do on the Main Oleo ??? whoosh ! and after the dusk take off the pilot beat the place up several times in full reheat !!!!

My last place of work before I was de-mobbed was at the RAF Marham Engine bay and I had the good fortune to meet an RR Technician called Phil (second name escapes me) but he was part of the team of RR Controls Engineers during the Hot & High Trials. He said they used to modify the three \x93Amps\x94 for each Engine control \x96 Lane1, Lane 2 & Reheat on the fly and the aircraft often flew with different schedules installed on all four engines \x96 I think the aircraft at Duxford has these still fitted in the racks (??M2Dude??) but that\x92s another Tonka thing too; three control lanes. Were all these Amps combined into one black box??

They are always Amps in RR Speak?? The Spey 202 had \x93Amps\x94 in its reheat system too.

I was lucky to find a job with the TVOC in 2001 until they ran out of money (as they do) and worked to have their flight worthy Olympus 20202\x92s tested at RR Ansty but left before that happened. In fact I don\x92t know if it did happen though it was a CAA requirement. While I was there we were working with Alan Rolfe & Mike Batchelor of the RR Historic Engine Department were offering support too. (593\x92s were their responsibility also !!! Historic !!!) but I think that was unofficial until there was an agreement about the costs.

After that I worked in industrial applications of Olympus (and Avon) and worked on many installed Olympus in power generation but based on the 200 Series \x96 I think the 300 was thought to be too fragile. But I did have a good look at Olympus 2008/003 Still in good working order in Jersey on the Channel Islands with it\x92s Bristol Sidderly Name plate on it. They didn't have Inlet Guide Vanes as the 300's had but just 6 Forward Bearing Supports, hollow with anti -Icing air blown though, controlled by a Garret Air Valve.

I never saw a DEBOW sort of function on the Industrials but there is a critical N1 speed which has to be avoided because the LP Turbine Disc can fail. The Trouble with that speed range is that it is right where the usefull power is produced!!! Was there any Normal Operating Range RPM's which had to be avoided on the 593 ?

Again thanks very much for all the fascinating information here\x92s to another 42 pages!! Sorry to have rambled on so much

Howie

Great thread, its taken some time to read through
The anecdotes from landlady , m2dude and the others are great

My main recollections are after coming back from Detroit to LHR, sitting on the National Express bus at dusk as Concorde took off from the runway parallel to the road, the whole bus shaking and watching the 4 engines glowing blue as she took off - brilliant. Sadly after that the next experience was passing 4 of them parked up after the AF disaster

As an Engineer I love things that push the envelope and limits - Concorde is one of those
Having just returned from Chicago on a 767, as capable as it is, I know what I would prefer to be riding in

I sadly doubt that we will see these flying again but I really would like to see effort in the next supersonic airliner rather than A380's and the like

quote:I remember at Fairford in mid 1974, a CAA test pilot (I honestly forget the gentleman's name) was taking the British pre-production A/C 101 (G-AXDN) for a special test flight.unquote

It was almost certainly Gordon Corps, possibly the finest 'engineering' test pilot I have ever worked with. After Concorde certification Gordon went to work at Toulouse wher he did most of the development flying that led to the A320 FBW system. BZ was the public 'face' of the design, but knowing the two men I have a very shrewd idea as to who did the original thinking! Perhaps Andy could confirm?

Tragically Gordon died young whilst trekking to an A300 crash site somewhere in the Himalayas

ClivL

Ref the landing manoeuvre: CliveL is quite correct - there was a distinct nosedown pitch generated by descent into gnd effect.

The machine was very light in pitch on approach (spring feel only and not much positive stability, especially with the A/T active owing to its destabilising effect) so minimal pitch input was the order of the day. Then you descended into gnd effect and a steadily increasing pull was reqd to hold the desired attitude (any nose down change at this stage was a prelude to disaster!).

The overall effect was not unnatural, since it was similar to a flare and hold off in a conventional aircraft (although more Stearman than 747).

AFTER touchdown, selection of reverse caused a distinct pitch up, and if this was allowed to get hold it was a real problem to get the nose back down. As explained pages earlier this deprived you of braking ability.....for this reason both pilots pushed the control column firmly forward after nosewheel touchdown, and I'm guessing that's what ChristiaanJ meant .

I've pulled this quotation out at random from what I have found a rather disappointing sequence of postings. I could write reams about this (and like everyone in this thread I would write as a Concordophile), but I won't - or at least I will try not to. In general I'm with Christian on this, and for the record I think a few 'counterfactuals' should be recorded. I am not trying to reopen a sterile debate - as CJ has said irrevocable decisions have been made and the subject is done and dusted. However, let us remember that:

G-BOAF was, and is the property of BA; BAe and now AI are merely caretakers.
AI's statement cross-posted from the Heritage website strikes me as a very reasonable statement; we found that your roof is leaking, if you don't get it fixed it is going to get worse rather rapidly; if you (BA) agree and will pay us to do it we will take it indoors and fix it. I don't see any sinister intent here, and given the weather we have had in the UK over the past weeks it must be regarded as a happy, if fortuitous decision!
Those who know Filton will also know that there is nowhere that Alpha Fox could be stored under cover except in the hangar where she was first assembled. They will also know that this hangar is buried in the centre of the factory and nobody, in a post 9/11 world, is going to give more or less unrestricted public access to somewhere containing a lot of valuable real estate! So when BA took the decision to locate AF at Filton it must have been in the knowledge that she would live in British weather until some form of shelter could be organised.
That it has taken so long to (fail to) organise such shelter is regrettable, but the blame can hardly be uniquely allocated to AI. BA own the aircraft, BAe/AI had a 40% share in building the airframe, RR a 60% share in building the powerplant. IMHO they should all have chipped in to construct some sort of shelter - it was never on the cards that local enthusiasts could have raised enough in a short time.
Although 'Dude' says that all the UK airframes were left out in the weather, this is not exactly true is it? 002 at Yeovilton (certainly) and 101 at Duxford (I think) are under cover and receive lots of TLC. It is at least arguable that these early airframes have more historical significance than Alpha Fox.

So far as AI's decision to hand back the C of A is concerned, they would have already recognised from the post-Gonesse activity that most people with sufficient expertise on the Concorde design were retired (or worse!) They have enough people to keep a subsonic aircraft going, but Concorde would, I think, require additional experience. AI management would certainly have consulted AI Engineering about this, and I have to say that the then Head of Engineering was someone I know well. He, like me, worked on Concorde in the early days and he is definitely not antiConcorde. I for one would respect his decision.

So far as the decision to stop services goes, we all knew they would be cut off sometime.the only question was when. When we were designing the aircraft the general feeling was that she would stay in service for about 30 years, but we also feared that it would only need one fatal accident to bring the whole lot crashing down. [Incidentally, it was that latter philosophy that made us (we hoped) ultracareful with airworthiness issues] In the event it was 28 years and one accident.
Even before Gonesse AF were losing money on their Concorde services. One might have thought that they would stop right away, but I suspect that a combination of Gallc pride and politics ensured that they would carry on.
But eventually there came a point where, on an airline losing money and in a recession, an unsentimantal and yes, generally unsympathetic, management would have to say enough is enough.
What else would you have them do? Continue to fly loss making services so that their rival BA could go on with their profitable? operations? One would have to say 'Get real!'
Once AF had decided to stop, what do you expect of AI? They are a company with a duty to make profit for their shareholders. OK, they had a duty, also to support in service aircraft, but that duty does not extend to doing that at a loss. With AF out of it therefore AI had no alternative but to ask BA to shoulder the full bill. I have no doubt that when BA declined to do this AI breathed a huge sigh of relief, but at the end of the day the decision to stop all Concorde services was above all an AIRLINE decision.

Sorry to go rabbiting on, but it is a subject that arouses strong emotions!

CliveL

May I echo a plea that ChristiaanJ has already posted on this thread, and respectfully suggest that we try and keep this thread free from opinions and debate about the Gonesse accident and the subsequent withdrawal of Concorde from commercial service?

Most contributors to this thread will doubtless have strongly held opinions and views on both these topics. Some have posted comments here, but whilst I respect their views and their knowledge, are not these topics already more than adequately catered for on other threads and forums? Frankly, I have to confess that I have grown weary with most such threads, and, in general, neither read them nor contribute to them.

I do, however, greatly value having just one Concorde thread devoted purely to technical comments, anecdotes and personal reminiscences. Perhaps, if others feel similarly, we might try and keep this thread that way?

Happy New Year

Bellerophon

Not quite the case, although the potential for a very rough ride was always there. Bill Weavers accident was the only one that involved an unstart, and was due in no small part to the test nature of the flight - CG out the back door. In Bills own words,

Concorde Profitability
Ahhh that question again. Just concentrating then on matters on the UK side of the English Channel. Prior to the Paris crash, BA was making a very healthy profit indeed on it's Concorde operation. There were some blots on the horizon that had to be overcome (Relife 2, SFAR regulation implementation, EGPWS and GPS navigation enhancement etc.) but all these things were 'doable' and under both study and disussion.
After the Paris crash came the horrible events of 9-11; around 40 regular BA Concorde passengers were tragically lost in the twin towers alone. When the aircraft returned to service in November 2001 the loads (and profitablity) were understandably taking a major hit, but as all times in her service life Concorde had the ability to weather the storm and was already bouncing back well. Unfortunately in 2003, due to some totally disgusting goings on, on the French side of the Channel, the aeroplane never got the chance to fully recover and BA services ceased in October of that year. (It is to the eternal shame of certain individuals on THIS side of the Channel that this French Disconnection was never challenged legally).
Concorde was only ever run (that is at least in the UK) for profit, but the hike in oil prices would obviously pushed up ticket prices significantly, and the massive economic downturn of last year would have certainly meant a temporary reduction in services. But in spite of all this, I firmly believe that Concorde would have weathered this storm, and would have been now earning those bucks for BA yet again.

John Hutchinson - The Wind Beneath My Wings
A superbly interesting read, written about arguably the most eloquent of all Concorde pilot speakers. One of lifes true gentlemen and a superb pilot, it is a long overdue biography, well done Hutch.

Best Regards
Dude .

71 pages later my personal edification is complete!! All contributors, particularly the 3 venerable concateers (you know who you are!), many thanks for the most captivating of insights.

3..2..1..Now indeed! Bravo I salute you !!

sAx

PS Having watched the Concorde Story, some consideration of sorts would need to be taken of events in the immediate aftermath of the Gonesse crash. AF from their perspective took the responsible position to ground aircraft, where BA continued flights later that evening following a business as usual approach. This proved quite upsetting on the French side of the Channel, as reasons behind AF4590's crash where unknown at that stage. The Gonesse Mayor being very critical about what appeared to his eyes to be a quite callous BA attitude, placing commercial consideration before public safety.

To rule any two individuals, the age old philosophy is to divide them. By the time recriminations started to fly from the BA side concerning AF maintenance standards, then the joint collaboration had achieved this for themselves. This left little room for manoeuvre for the CAA, who had to be seen to be placing the public interest before any cash as usual continuity. Their stance would need to be unequivocal, showing the public that the 'gamekeeper' would not be making any attempt to be seen in collusion with the 'poacher' and hence removal of the air worthiness certificate. This is not a riposte of any previous post, but just my $0.02c of what may have played a contributory part in the final decision to retire Concorde. Regardless of any attempt to present a united front, the end result may well have been the same. but it would have gone someway to underline public confidence in the responsible attitudes of both AF and BA.

BA made the right call regarding continuing to fly their Concordes following the crash, and it was a massive mistake by the CAA to ground the British fleet. The whole crash has been one massive cover-up by the French who operated Concorde badly with regard to their maintenance procedures. The crash lies firmly at the door of Air France.
Of course we could go into the list of near crashes by Air France, such as the time when they topped up the hydraulic fluid on Concorde SD with the wrong fluid. The French had problems with their Concordes that the British never suffered, and I am surprised that there were not further crashes with their fleet.
Well done BA for a wonderful nearly 28 years of safe supersonic passenger services!

The Concord was scrubbed because when ran as an airline, using typical overweight, RTO type mentality, it's was an accident waiting to happen.

Reminds of the Shuttle...Rutan gets a plane in space...for one billionth the price...so the Shuttle goes away because the people can't keep costs down.

Maybe all this should be put into the private sector where people 'try'.

gordonroxborough
Speaking as someone who was actually THERE during the entirity of Concorde commercial operations (rather than just an amature outside observer), I can assure you that replacement doors were almost always painted when fitted to the aircraft, and NOT left in the green primer colour. Alpha Charlie was a bit of an exeption in that the door was never painted and THAT is the point being made here. No one is even suggesting a freak of nature for goodness sake, and no matter what you may have read etc, this was regular Concorde engineering practice.

whenrealityhurts
Wow, what total and absolute drivel. For a start it's CONCORDE and not that rather wonderful town in Middlesex County thank you very much. There was NEVER any 'operated using typical overweight RTO mentality' this side of the English' Channel EVER and anyway this had absolutely NOTHING to do with the assasination of the amazing aeroplane.. As far as being 'an accident waiting to happen', well you are obviously at best very poorly informed and at worst you are used to speaking out of an orifice diagonally opposite to your mouth sir.
Galaxy Flyer has made a large number of very valuable contributions to this thread and as an ex C5A pilot and highly experienced aviator deserves infinately more respect than you. As far as any bannings here, well look in the mirror fella, and I suggest that you restrict your postings to something that you maybe have some expertise. (Is there a section here on paper aeroplanes maybe?).

Regards (particularly to you GF) Dude

I second that M2Dude and thank you for correcting this m*ron




Interesting how this 'accident waiting to happen' enjoyed a thirty year plus accident free record with BA.

Hi Guys,
first, thank you for this wonderful thread!!!

AFAIK , the FDR of Concorde hasn't been discussed here yet.
What are it's capabilities, i.e. parameters logged, speed, capacity, etc. ?
Where is it located?
Did it survive the Paris crash? If so, did the investigators get useful data from it?

Thanks much in advance.

The FDR is Located in Racks at the Rear of Concorde"s Rear cabin near the emergancy doors.

Which also contain other Boxes such as the Radio Tran-ceivers, ADF receivers and Intake Computers among them which are all coverd over and out of site!

They did survive the Paris Crash from memmory.

This has info on the FDR and Accident!

It is Gordons website!

CONCORDE SST : Accident Report

hi guys, thanks for a very informative thread.
In the mid 70s I lived in a thatch cottage 31nm west of LHR at the bottom of a hill in the Thames valley.
One particularly grotty dark autumn evening our cottage started shaking, I rushed out into the dark expecting to see a car crash but realised it was a low flying aircraft. (I wasn't a stranger to low aircraft noise as we were in the Greenham Common circuit and the F111 had been based here when Upper Heyford was resurfaced).
I later read that droop snoop had an engine go into reverse in cruise.
The subsequent report in the horror comic was of it's following take off when it happened again on rotate.
What I remembered was some sort of award to engines or probably the whole crew and that she didn't get above three thou until crossing the Bristol coast.
questions...
Was it a simple electrical failure?
Was there any protection to stop it happening again?
Was there a significant speed loss when it happened?
Was there a problem with the adjacent engine?
Flying questions.
What was the engine out climb procedure?
Was there another double engine failure procedure as on the iron duck with immediate fuel dumping?
Was it just a coincidence that the flight was routed outside of CAS but along the Thames valley avoiding the high ground to the north and Membury mast?
Thanks
sorry if it has already been covered but have only got through to page 50...

For the french speaking (or reading) people here, I just found a mine of very interesting informations about Concorde on this website:
Accueil
This site has a database of thousand of concorde flights with the following datas: Date and time of the flight, airframe used, technical and commercial crews, guests, departure/arrival airports and flight type (regular, charter world tour...).
On top of that, many infos and stories around Concorde can also be found there.
I can't resist to translate one of those stories (I'm far from being a native english speaker or a professional translator; so forgive me for the misspellings and other translation mistakes). It is a report about one of the biggest incident that happened to the prototype 001 during the flight tests:

Shock of shockwaves
We were flying with Concorde at Mach 2 since 3 month already on both side of the Channel. The prototype 001 did outstrip 002 which was supposed to be the first to reach Mach 2.
Unfortunately, a technical issue delayed 002 and Brian Trubshaw fairly let Andr\xe9 Turcat be the first to reach Mach 2 with the 001 which was ready to go.
The flight tests were progressing fast and we were discovering a part of the atmosphere that military aircrafts hardly reached before. With Concorde, we were able to stay there for hours although limited by the huge fuel consumption of the prototypes.
The Olympus engines did not reached their nominal performance yet and, most of the time, we had to turn on the reheat in supersonic cruise to maintain Mach 2.
The reheat is what we call afterburner on military aircrafts. Fuel is injected between the last compressor stage of the low pressure turbine and the first exhaust nozzle. This increases the thrust for the whole engine and its nozzle.
The 4 reheats, one for each engine, are controlled by the piano switches behind the thrust leavers on the center pedestal between the two pilots. Air was fed into the engines through 4 air intakes, one for each engine, attached 2 by 2 to the 2 engine nacelle, one under each wing. The advantage in terms of drag reduction was obvious.
However, tests in wind tunnel showed that, at supersonic speed, if a problem happens on one engine, there was a great chance for the adjacent engine to be affected as well by the shockwave interference from one air intake to the other despite the presence the dividing wall between the two intakes. So we knew that an engine failure at mach 2 would result in the loss of 2 engines on the same side, resulting in a lateral movement leading to a strong sideslip that would likely impact the 2 remaining engines and transform the aircraft into the fastest glider in the world.
This is why an automatic anti sideslip device was developed and installed on the aircrafts.
The air intakes are very sophisticated. At mach 2, it creates a system of shockwaves that slows down the air from 600 m/sec in front of the aircraft to 200 m/sec in front of the engine while maintaining a very good thermodynamic performance. In supersonic cruise, the engines, operating at full capacity all the time, were sensitive to any perturbation and reacted violently with engine surge: the engine refusing the incoming air.
Stopping suddenly a flow of almost 200kg of air per second traveling at 600m/sec causes a few problems. As a result, a spill door was installed under the air intake and automatically opened in such event.
To control the system of shockwaves and obtain an efficiency of 0,96 in compression in the air intake, 2 articulated ramps, controlled by hydraulic jacks, are installed on the top of the air intakes in front of the engines. Each ramp is roughly the size of a big dining room table, and the 2 ramps, mechanically synchronized, move up or down following the instruction of an highly sophisticated computer that adapts the ramp position according to the mach number, the engine rating and other parameters such as skidding.
At that time, it was the less known part of the aircraft, almost only designed through calculation since no simulator, no wind tunnel, did allow a full scale test of the system.
The control of the system was analog and very complex but it was not easy to tune and we were moving ahead with a lot of caution in our test at mach 2.
On the 26th of January 1971, we were doing a nearly routine flight to measure the effect of a new engine setting supposed to enhance the engine efficiency at mach 2. It was a small increase of the rotation speed of the low pressure turbine increasing the air flow and, as a result, the thrust.
The flight test crews now regularly alternate their participation and their position in the cockpit for the pilots.
Today, Gilbert Defer is on the left side, myself on the right side, Michel R\xe9tif is the flight engineer, Claude Durand is the main flight engineer and Jean Conche is the engine flight engineer. With them is an official representative of the flight test centre, Hubert Guyonnet, seated in the cockpit's jump seat, he is in charge of radio testing.
We took off from Toulouse, accelerated to supersonic speed over the Atlantic near Arcachon continuing up to the north west of Ireland.
Two reheats, the 1 and the 3, are left on because the air temperature does not allow to maintain mach 2 without them.
Everything goes fine. During the previous flight, the crew experienced some strong turbulence, quite rare in the stratosphere and warned us about this. No problem was found on the aircraft.
We are on our way back to Toulouse off the coast of Ireland. Our program includes subsonic tests and we have to decelerate.
Gilbert is piloting the aircraft. Michel and the engineers notify us that everything is normal and ready for the deceleration and the descent.
We are at FL500 at mach 2 with an IAS of 530 kt, the maximum dynamic pressure in normal use.
On Concorde, the right hand seat is the place offering the less possibility to operate the systems. But here, we get busy by helping the others to follow the program and the checklists and by manipulating the secondary commands such as the landing gear, the droop nose, the radio navigation, comms, and some essential engine settings apart from the thrust leavers such as the reheat switches.
The normal procedure consists in stopping the reheat before lowering the throttle.
Gilbert asks me to do it. After, he will slowly reduce the throttle to avoid temporary heckler. Note that he did advise us during the training on the air intake to avoid to move the thrust leaver in case of engine surge.
As a safety measure, I shut down the reheat one by one, checking that everything goes fine for each one. Thus I switch off the reheat 1 with the light shock marking the thrust reduction. Then the 3\x85
Instantly, we are thrown in a crazy situation.
Deafening noise like a canon firing 300 times a minute next to us. Terrible shake. The cockpit, that looked like a submarine with the metallic and totally opaque visor obviously in the upper position, is shaken at a frequency of 5 oscillation a second and a crazy amplitude of about 4 to 5 G. To the point that we cannot see anymore, our eyes not being able to follow the movements.
Gilbert has a test pilot reaction, we have to get out of the maximum kinetic energy zone as fast as possible and to reduce speed immediately. He then moves the throttle to idle without any useless care.
During that time, I try, we all try to answer the question: what is going on? What is the cause of this and what can we do to stop it?
Suspecting an issue with the engines, I try to read the indicators on the centre control panel through the mist of my disturbed vision and in the middle of a rain of electric indicators falling from the roof. We cannot speak to each other through the intercom.
I vaguely see that the engines 3 and 4 seem to run slower than the 2 others, especially the 4. We have to do something. Gilbert is piloting the plane and is already busy. I have a stupid reaction dictated by the idea that I have to do something to stop that, while I can only reach a few commands that may be linked to the problem.
I first try to increase the thrust on number 4 engine. No effect so I reduce frankly and definitively. I desperately look for something to do from my right hand seat with a terrible feeling of being helpless and useless.
Then everything stops as suddenly as it started. How long did it last, 30 seconds, one minute?
By looking at the flight data records afterward, we saw that it only last\x85 12 seconds!
However, I have the feeling that I had time to think about tons of things, to do a lot of reasoning, assumption and to have searched and searched and searched\x85! It looked like my brain suddenly switched to a fastest mod of thinking. But, above all, it's the feeling of failure, the fact that I was not able to do anything and that I did not understand anything that remains stuck in my mind forever.
To comfort me, I have to say that nobody among the crew did understand anything either and was able to do anything, apart from Gilbert.
The aircraft slows down and the engine 3 that seemed to have shut down restart thanks to the auto ignition system. But the 4 is off indeed.
Michel makes a check of his instruments. He also notes that the engine 4 has shut down but the 4 air intakes work normally, which makes us feel better. After discussing together, we start to think that we probably faced some stratospheric turbulence of very high intensity, our experience in this altitude range being quite limited at that time. But nobody really believes in this explanation. Finally, at subsonic speed, mach 0.9, with all instruments looking normal, we try to restart engine 4 since we still have a long way to go to fly back to Toulouse.
Michel launches the process to restart the engine. It restarts, remains at a medium rotation speed and shuts down after 20 seconds, leaving us puzzled and a bit worried despite the fact that the instrument indicators are normal.
Gilbert then decide to give up and won't try to restart this engine anymore and Claude leaves his engineer station to have a look in a device installed on the prototype to inspect the landing gear and the engines when needed: an hypo-scope, a kind of periscope going out through the floor and not through the roof.
After a few seconds, we can hear him on the intercom:
"Shit! (stuttering) we have lost the intake number 4."
He then describes a wide opening in the air intake, the ramp seems to be missing and he can see some structural damages on the nacelle.
Gilbert reacts rapidly by further reducing the speed to limit even more the dynamic pressure.
But we don't know exactly the extent of the damage. Are the wing and the control surfaces damaged? What about engine 3?
We decide to fly back at a speed of 250 kts at a lower altitude and to divert toward Fairford where our british colleagues and the 002 are based. I inform everybody about the problem on the radio and tell them our intentions. However, I add that if no other problems occur, we will try to reach Toulouse since we still have enough fuel.
Flying off Fairford, since nothing unusual happened, we decide to go on toward Toulouse. All the possible diversion airport on the way have been informed by the flight test centre who follows us on their radar.
At low speed, knowing what happened to us and having nothing else to do but to wait for us, time passes slowly, very slowly and we don't talk much, each one of us thinking and trying to understand what happened. However, we keep watching closely after engine 3.
Personally, I remember the funny story of the poor guy who sees his house collapse when he flushes his toilets. I feel in the same situation.
Gilbert makes a precautionary landing since we don't rely much on engine 3 anymore. But everything goes fine.
At the parking, there is a lot of people waiting for us and, as soon as the engines stop, we can see a big rush toward the nacelles of the right hand side engines.
Gilbert and myself are the first to get off the plane and we are welcomed down the stairs by Andr\xe9 Turcat and Jean Franchi who came out from the crowd watching at the right hand side nacelle.
They both behave the same way, with a slow pace attitude, the same look, a mix of disbelief and frustration.
Andr\xe9 is the first to speak: "I can't believe we were not on this flight, really unlucky\x85". Yes, this flight was supposed to be just a routine flight\x85!
The condition of the nacelle is impressive. We come closer and everybody move aside for us with a look of disbelief and respect as if we were hell survivors.
The ramps of the intake 4, those 2 "dining tables", have completely disappeared leaving a hole where we can see the hydraulic jacks and the stub rod where the ramps were attached.
Indeed, only the ramps were missing, apparently ejected forward which was unbelievable knowing how fast we were flying. The ramp slipped under the nacelle causing some damages on it and on the hood of one of the elevon's servo control. Fortunately, the control did not suffer any damage.
What is left of the rear ramp seems to be blocked down inside the intake in front of the engine and we can see behind it the first blades of the compressor, or what is left of it, not much.
The engine swallowed a huge amount of metal but no vital parts of the aircraft has been damaged, no hydraulic leaks, no fuel leaks. I remembered at that time the stories of some B58 Hustler accident where the loss of an engine at mach 2 almost certainly ended with the complete loss of the aircraft. Our Concorde has only been shaken. This incident strengthened the trust I had in this plane. And I was not unhappy to have experienced this ordeal, especially when I saw the frustration on the face of Andr\xe9 Turcat and Jean Franchi.
But we had to understand what happened and how; and also why the ramp's fixing broke.
It didn't take much time to get the answers.
I unintentionally triggered the problem when shutting down the reheat of engine 3. The sudden stop of the fuel flow did of course stop the combustion and the back pressure behind the low pressure turbine. But, probably because of the modification made on the engine before the flight, the stop of the reheat has not been followed by the normal closing movement of the primary nozzle to compensate the pressure drop. So the low pressure turbine ran out of control, dragging down the low pressure compressor which reacts by surging.
Despite the opening of the spill door, the engine surge led to a sudden movement of the shockwaves in the air intake creating a surge in the intake itself. A similar surge happened in the adjacent intake 4 followed by a surge of the corresponding engine. This caused an excessive pressure above the ramps and the fixings of the intake 4 did not hold.
Since it was the first time we experienced a surge in the air intake, we had little knowledge of the stress it would create on the ramps. This led to miscalculation of the strength of the ramps's frames and they did brake.
Another mistake: instead of installing the motion detectors on the ramp itself, to make the production easier, they have been placed on the arms of the hydraulic jacks. This is why Michel R\xe9tif thought that the position of the ramps were correct. The hydraulic jacks did not suffer any damage and were still working normally even if the ramps were missing.
All the data recorded during this event helped us in redesigning the air intakes and the flight test program resumed three month later.
After this, we deliberately created dozen and dozen of air intake surge to fine tune the way to regulate them with digital calculator this time.
From now on, even if it was still very impressive, it was safe and their intensity was not comparable with what we experienced with the missing ramps.
However, a french president may kept a lasting memory of this, much later, during a flight back from Saudi Arabia. This time, I was on the left side, Gilbert on the right and Michel was still in the third seat\x85 But that's another story.
For me, the lasting impression of failing and being helpless during this incident made me wonder what a commercial pilot would have done in this situation. This plane was designed to be handled by standard commercial pilots and not only by the flight test pilots.
At that time, I was interested in taking in charge the management of a training center for the pilots of the future Airbus's clients. This event pushed me that way and I made it clear that I wanted to add the flight training on Concorde in this project. This has been agreed and I did it.
And the Concorde training program now covers the air intake surges and how to deal with them.
Jean PINET
Former test pilot
Member and former president of the Air and Space Academy

Not really. For one thing, the 2707 design was only at the mock-up stage when cancelled, so the practicalities of its engine arrangement hadn't been touched on. If you go back and read the Ted Talbot 'oil and lamp black' story, you can see for yourself that Concorde had solved problems that even US military designs were struggling with half a decade later.

As for the Concorde nacelle/engine arrangement - it didn't really have that large an impact on the F-BTSC accident - because even if the nacelles weren't grouped, the hot gases from the burning fuel would still have had a negative impact on the airflow to the adjacent engine. If I recall correctly, the investigators calculated the way the damage spread through the structure and control connections and proved that even if all four engines were still producing the correct thrust, the fire would still have caused sufficient structural damage to prevent the aircraft making Le Bourget. The nacelle structure itself was proven to be strong enough to withstand an uncontained failure of the engine when it actually happened on the line.

Apropos of nothing, the separate "podded" design was proven to be no protection against damage to adjacent engines when the inboard starboard engine of El Al 1862 took out the outboard as it fell away.

For those willing to search out a podcast:
166 ? Flying the Concorde | omega tau

This time we talk with former Concorde pilot John Hutchinson about flying this Mach 2 airliner. We discuss the cornerstones of the design and construction of the aircraft, its operation (mostly with British Airways), flying characteristics as well as the infamous accident in Paris in 2000 (on which John has some very specific opinions).