Posts about: "Intakes" [Posts: 171 Page: 4 of 9]¶

Dude - I think basic engine hardware was in good supply, but there were concerns about the control amplifier component availability.

We have a couple of Olympus intake blanks which we find absolutely perfect for gardening with our aged knees.

Yes, I can imagine they would be perfect for that!
Not to mention the vast quantity of spare compressor and turbine blades and stator vanes, spread far and wide after the end-of-service, through the spare parts auctions.



(The model is a design that was part of my engineering studies - late '60s - but the compressor vane is real Concorde.)

Tell us more?
M2dude and myself already have mentioned the same problem with the AICU (air intake control computer) in this thread.
People do only rarely realise how rapidly technology was changing in the early Concorde days, and how difficult it was to procure components that sometimes were already obsolete when Concorde entered service.

CJ

Dude, only 5 seconds ?? I'd demand a re-edit mate...outrageous !

Out of interest...here is a pic of AG in Seattle ( taken a while back ) and the source of a big part of this thread - unfortunately could not get any higher in order to get a better view...on either end ! ( I need to check on her again and see how she is doing ) and the SR71 also ( from the Pima Air / Space museum in Arizona) - I am sure all have seen the Concorde intakes but the SR71 rear end is interesting....

ps Please forgive the pic of the Sikorsky ( at Pima also ) ...couldnt resist

Cheers...

Hi DavvaP, and welcome. As far as ice on the wing goes, I'm sure as any of my pilot friends here will agree that she was treated just like a subsonic in that regard; any ice or snow build up on the surfaces of the wings would not be tolerated and would have to be removed before flight. (She may have had a revolutionary wing design, but still this was a wing nonetheless ). She would also require pre-flight chemical anti-icing/de-icing treatment from a ground truck just like the rest, in shall we say, 'less than tropical conditions'. (Winters in Prestwick during crew base training... such fond memories ). As far as active ice protection on the wings, there was a highly sophisticated Lucas electrical 'spraymat' system fitted, but only the wetted areas of the wing, forward of the engines were 'covered'. Two digitall cyclic timers (CTPUs) would automatically regulate cyclic switching on and off of 115 VAC for various load areas of the wing at a time at pilot pre-selectable intervals (2, 4 or 8 seconds). Also as part of this system, there was continuous de-icing for certain other load areas too, so you had a mix of cyclic and continuous de-icing in operation. The whole idea here was to prevent chunks of ice entering and damaging the engines, the only other areas of this electrical de-icing system were the intake lips and side-walls and also the D Box area above the auxilliary inlet vane, built into the spill door. (This would only operate if the auxilliary inlet door itself was open). The whole shooting match would automatically switch itself off, for obvious reasons, above a TAT of 15\xb0 C. (ie. the vast majority of the flight). The only other de-icing system (apart from the galley drain masts) was on the engine inlet guide vanes, but this was purely pneumatic and again would swith itself off above 15\xb0 C.
I think you will find that precious little of Concorde is now not generally available in the public domain, some control software and laws are still I would expect covered by some sort of patent. (That is why when I publiished here the engine 'E Schedule' graphs I deliberately deleted the equations for the various running lines.
Your efficiency question was a valid one; as IAS and Mach number increase the aerodynamic drag (in all it's forms) will generally increase, but the efficiency OF A WELL DESIGNED powerplant wil also increase, and Concorde was definately no exception here. The real beauty of Concorde was just HOW MUCH the powerplant efficiency increased with increasing speed and more than totally eclipsed the aerodynamic drag rise with this increasing speed. At supersonic speeds, the closer you could fly to Vmo/Mmo the lower the fuel burn was. (Especiall true at Mach 2, although the autopilot would hold you Mach 2 (ish) in Max Cruise mode, flying closer to Mmo, Mach 2.04, would save fuel, assuming the static air temoerature was low enough to sustain this). This fact (along with about a million others) produced what we all like to call 'The Magic of Concorde'

Best Regards
Dude

Mr Vortex
Finally as promised, here is a schematic of the AFT part of the fuel vent system. As you can tsee the fin intake pressurises the air space above tank 11, and hence, via the Scavenge Tank air-space, the remaining tanks. (Also you can see the Trim Pipe Drain Vaves you were asking about.



Regards Dude

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

howiehowie93
Welcome aboard and thank you for your kind words; I am so glad you enjoy our thread. You are in good company here also, many of the 'more mature' vintage Concorde people (like me) are ex-RAF. (And some of the pilots were ex-RN also, but no one is perfect ... only joking guys).
It is a matter of pride/embarrassment for me that up to the end of 2003, I'd only ever really 'known' two aircraft; the C-130 and Concorde .
I was really interested in some of the RB199/Olympus similarities; TBP was tried on the development aircraft for engine control TET calculation, but Rolls-Royce were unhappy with the performance and abandoned TBP in favour of indirectly computing TET as a function of T1 (intake TAT) and EGT (T7). (And this meant the removal of the four TBP amplifiers too... we had even more black boxes then.
As for the three 'control amps' you were speaking of, I'm 99% sure that A/C 101, G-AXDN still does have the units you described fitted. The ECUs (or ECAs as they were sometimes called) were a highly complex analog control unit built by Ultra Electronics. They could be quite a headache sometimes in terms of reliability, but would generally perform flawlessly in terms of engine control. As with any analog box, control law changes in the field were not too straightforward and a soldering iron was the flight test engineers best friend here. The Reheat Amp was built by ELECMA (the electronics arm of SNECMA) and unlike some of the other components in the reheat system, was a beautifully designed and constructed unit. Very few reheat failures (and there were many) were attributed to the 'box' itself. The main fragility with the reheat system was the ignition system used (a 20 KV swirl ignitor, which you will see is covered previously in the thread). We (BA/RR) were seriously looking at one point of investigatng the use of 'hot streak' injection as a backup ignition source, which I believe was used in the 199 (?), but it unfortunately never happened. The Plessey DECU that was tried on A/C 202 (G-BBDG) DID combine main engine control and reheat, but unfortunately was never taken up for the production A/C, and so we were left withe the '3 AMPS' as you so eloquently describe. We had a total of THIRTY ONE control units associated with powerplant control on Concorde; might be a little different now methinks ]
Thanks for some of the fascinating engine history snippets you shared with us, although purists might regard it as being 'off topic' I personally think this rather unique thread is all the better for your contribution here,
I think it is great that you are working with industrial Olympuses, all part of the family tree. I will dig out the verboten sustained N1 speed band for the 593, it certainly WAS a fact though.
Thanks from all of us for your contribution here Howie, keep on posting.

Regards
Dude

howiehowie93
The whole idea of adapting hotstreak injection came from our Rolls-Royce rep', who spent many years on RB199 development. We'd even identified the position on the Olympus 593 for the injector itself; un unused start atomiser port, but as I reluctantly said before, it was not to be.
Apart from ignition issues the other main problems were reheat instability and reheat 'coming in with a thump', this particular malady being generally confined to transonic acceleration and not take-off.
The instability issue was caused by either an open circuit/high resistance fuel metering valve tacho (only rate feedback was used here) or more commonly contamination of the RFCU umbilical electrical connector. The connector itself was originally located high up the side of the engine, close to the combustion area, was barely accessable and was a total nightmare in terms of reliability. After a great deal of pressure from us (BA) SNECMA agreed to effectively relocate the connector at the bottom of the engine and the majority of our stability problems almost disapperared overnight.
The 'reheat in with a thump issue was a real beaut'. For transonic acceleration a much lower ratio of Fr/Fe (reheat fuel flow/engine fuel flow) was used than for take-off. (0.45 as opposed to 0.78) and therefore the opening rate of the fuel metering valve required damping, this being achieved by using a metered orifice inside the RFCU that applied a small amount of servo fuel pressure to one side of the valve to achieve the damping. Trouble was, any contaminants in the reheat fuel system would progressively clog up the orifice and kill our daming stone dead; the end result being the FMV banging wide open and hence the 'thump'. The only remedy for this problem was to replace the RFCU. SNECMA, in a truly classic feat of engineering produced a filter across this orifice, in order to prevent it getting clogged. Anyone see a problem with this? Yep, the filter itself would clog up and we got our beloved thump back. The only remedy for this problem was again to replace the RFCU. The contaminants were often as a result of RFCU build issues; this issue was never truly resolved.
I checked and found the dodgy sustained N1 band for the Olympus 593, this was 88-91% N1. This figure was never an issue in service as at cruise ISA -7 and above conditions the N1 was always run at the flat rate limit of 101.5%. Below ISA -7 the intake system would progressively reduce N1 as a function of intake local Mach Number, falling to 97.4% at ISA -24. (The coldest cruise conditions I personally ever saw was ISA - 25 (that's -81.5 degrees C folks) between BAH and BKK.
The controlled N1 at all other 'non cruise' phases was always in the upper 90's, well away from our blade resonance area.

jodeliste and Alpine Flyer
Thank you both for the TSR-2 information, it makes amazing reading (what a truly magnificent aircraft) , and as Concorde's military cousin, discussion here is in my opinion most waranted.

Regards
Dude

M2Dude

There was an unconfirmed report - so no doubt completely baseless - that ...er...another operator... noticed a rather unusual but highly favourable wind component on a JFK...er...Easterly... crossing, as they passed through FL520 or so, giving them a magnificent groundspeed.

Deciding that they would like to maintain this groundspeed, they went ALT HOLD and MACH HOLD at around FL530. They maintained their groundspeed, so the story goes, but the autothrottle then progressively reduced the N1, as the aircraft weight reduced, over the next couple of hours, into the prohibited range!

Did you ever hear of any such event?

Best Regards

Bellerophon

Greetings.

Service Bulletin 0420 Industrial Olympus Gas Generator \x96 LP Turbine Disc Cracking Safety Related Operational and inspection requirements.
to paraphrase:

Avoid steady operations in the range 5450 to 5850 RPM I believe that 100% is 8000RPM so that equates to 68 \x96 73%. It is ok the accelerate through that range apparently.


There seems to be a lot of history about Olympus LP Discs:
Test House 40 \x96 I think - at RR Ansty still has the deep groves in the brickwork where an engine broke up during test.
From Wikipedia:
\x93XA894 flew with five Olympus engines, the standard four plus an underbelly supersonic Olympus 320 fed from a bifurcated intake starting just aft of the wing leading edge and inboard of the main intakes, in a mock-up of the BAC TSR-2 installation. This aircraft was destroyed on a fire on the ground on 3 December 1962\x94

I read the LP Disc did a QANTAS A380 and decided to leave the engine:
An Aviation Heritage story

So there\x92s nothing new in the world really

regards
HH93

IMHO I'd the simplicity of the design. I have worked on many flavours of Gas Turbines since I left the RAF in 2000, GE, RR, Rustons, (EGT, RGT the same really just a name change every few years and now Siemens) oh and Solar - who I work for now - better not forget them !!

All these engines from other manufacturers have complicated systems to make them efficient:
VIGV's (Variable Inlet Guide Vanes)
VSV's (Variable Stator Vanes)
Bleed Valves
Multi Fuel Metering Valves & other valves to keep emissions under control.

The Olympus - nowt ! Two Spools and a Fuel Valve thats your lot. nothing to go wrong and being an Aeroderivative all the ancillary equipment is either bolted on underneath or away from the engine outside the enclosure.

The only thing I had trouble with was the burner bolts shearing off, 1/4"BSF, if never touched in a good few years !

Was it all still BSF on the 593? That was a Bristols thing - true RR designs are UNC (well Avons are anyway)

oh ! I forgot about the Hot Shot; when I was ground running installed RB199's there was no jump in TBT/T7, you couldn't sense it fire either, the only feel was either the Reheat lighting off with a big roar or the engine going quiet as the Nozzle opened up until the MECU noticed it hadn't lit and closed it again sharpish.

Good eh
Regards
H wie

Landroger
The great thing about the OLY593 was the high specific thrust (in relative terms the Olympus is a tiny, compact design), it's growth potential/high potential mass flow. A bypass engine is not really ideal for supersonic cruise, and given what was available in terms of two-spool turbojets in the 1960s, the Olympus was the obvious choice for both the TSR-2 and Concorde alike. As far as for ships and power stations, well a turbojet is always going to be favourite, as all the gas energy is contained in the jet efflux; this can be efficiently transferred to the load in question by a gearbox coupled to the HP spool.

howiehowie93
Well the 593 did require a primary nozzle to match N1 against N2, bur apart from that she was a study of deceptive simplicity and elegance.
No mate, generally BI-HEX AF.
This really is fascinating stuff Howie, thank you. As I alluded to a few pages back, the primary nozzle on the OLY593 opened in response to the rising P7, kind of 'after the horse has bolted' in a way. To maintain the correct scheduled value of N1, the control system set, via a needle valve, a finite ratio between P7 and P3. As reheat lit as P7 attempted to rise it upset this ratio and the primary nozzle was opened in order to restore the aforementioned ratio. (Nozzle opens, P7 falls). When reheat was cancelled the opposite happened, and the nozzle closed sharply to prevent N1 overspeed.

Tom355UK
Glad you are enjoying our thread, and thank you for your kind words. (But apologies to your good lady wife though ).
Jeepers Tom that is one hell of a question. Assuming there was a market for such a venture (personally not sure right now) I think you are looking at BILLIONS of $, and for this reason alone I think you'd find that a multi-national/continental effort would be required. There is little doubt that technology is not the major barrier here, but economics and political will. (Nice thought though, I do agree).
As far as a powerplant goes, well the PW5000 is a really superb engine, although well down on the thrust requirement for an 'NG' SST. More likely I would have thought would be e development of the Olympus, there was/is still such an enormous amount of potential in this basic design. (But who knows, this is all pure speculation anyway).
And have no fears about posting here Tom, most of us are quite happy to answer away (We've said before that there is no such thing as a stupid question; you are most welcome here ).

DavvaP It really did not matter what airframe we used for the test flight; the sole purpose was just to find out just what effect (if any) the tank liners had on the performance of the fuel system. (The handsome chap who you see on TV most, installing the liners, Mr Marc Morley left BA and now resides in Australia).
I am honoured to say that I was lucky enough to be onboard G-BOAF for that flight from LHR-BZZ and as far as I could tell, the liners had no impact whatsoever. One amusing part of the flight was when we deliberately allowed tank 3 to run dry and see just what the indicated fuel quantity was as #3 engine flamed out (we were subsonic at this point of course). The gauge slowly crept down (in order for the tank to to run dry, the tank 7 & 8 transfer pumps were switched off) and we all watched in eager anticipation/dread....... as the counters reached zero weeeeeee... the engine flamed out. I am being completely honest here, the engine wound down EXACTLY at ZERO indicated contents).
Those 7 aircraft really did look magnificent I know, it was just sad as to the reason they were all lined up there.

Mr.Vortex
Well she was a delta without a tailplane, so the short answer is 'yes', but remember that we used fuel to move the CG backwards and forwards for long term trimming.
OK, this is a little complicated, so bear with me. The intake had a finite limit, in terms of the mass flow that it could deliver to the engine and so an automatic N1 limitation signal was transmitted from the intake 'box' (the AICU) to the engine 'box' (the ECU) full time above Mach 1.6. Now this limitation was referenced against TEMPERATURE compensated N1, ( N1/ \xd6 q) and at normal ISA temperatures this limit was above the 'normal' 101.5% N1 running line. (The lower the temperature, the lower the effective limit became). At ISA -7 the limit now became less than 101.5% N1, and so the demanded value of N1 was reduced to this value. But this limit signal was always there, it's just that at normal temperatures it was effectively ignored by the ECU. If this limitation signal failed for any reason, the AICU would detect this by way of the ramp angle becoming uncomfortably close to it's MINIMUM variable limit (this limit was scheduled as a function of intake local Mach number) and an amber light would illuminate on the associated N1 gauge, along with an amber INTAKE master warning would illuminate (plus an audible 'BONG' from the audio warning system). The only course of action was to manually reduce throttle setting away from the Mach 2 norm of maximum, in order to reduce N2, and consequently N1 and mass flow demand. There was in intake pressure ratio indicator at the top of the intake control panel that would show where the power setting would have to be set to. It was an indirect indication of intake shock geometry.
This manual N1 datum reset control was only used during flight test trials into just how much N1 would have to be controlled/reduced at low temperatures in order to give optimim intake geometry. It had absolutely nothing to do with afterburner/reheat and had no place in the production aircraft as all the research was complete

Best regards to all
Dude

A certain CFI (I think) at BA flying club, High Wycombe, who was also F/O on concorde, showed me some photographs of an engine that had eaten a piece of intake ramp.
I think he said that the adjacent engine had surged and a piece of ramp went out the front and down the other engine. This resulted in a double engine failure mid atlantic. They landed in Shannon with very little fuel left.

A double engine change ensued.

Question, how fast was the ramp going if the A/C was at Mach 2?

Maybe M2dude remembers the occasion?

First time that happened was on prototype 001 in the very early days, when an engine "spit out" the entire ramp (there's a photo in Trubshaw's book).
The ramps and actuators were 'beefed up' considerably afterwards... I didn't know an in-service aircraft had suffered a similar mishap.

Good question.... not being an "engine man" I've always been amazed how a nice steady Mach 2 flow, slowed down to Mach 0.5 at the engine inlet, is capable of totally choking off and even reversing itself in less than a second.... no wonder it's usually accompanied by a big bang!

CJ

PS I have no record of any of the British development aircraft ever having lost a ramp, notwithstanding the number of deliberate engine surges they went hrough. But then maybe I wasn't told....

Hi Guys, quite a few little points here, so here's my angle(s):
Pedalz
Ooo yes. The biggest problems we ever had associated with the ramps themselves were wear in the seals at the sides of the forward ramp. Even a few thou' over the maximum allowable side gap was enough to make the intake unstable and susceptible to surging. (It is quite interesting that the rear ramp side gaps were not in the least bit critical, and if Concorde intake development had continued, the rear ramps were going to be deleted altogether). Other failure factors were control unit malfuntions, rapid sensor drift; all of these causing either ramp/spill door drift or runaway. Primary nozzle misbehaviour could also result in intake surges. Having said all that, the monitoring of the intake system was truly superb, and surface runaways, themselves quite rare, would usually be picked up by the control system monitors causing either a lane switch or if that did not work, a total 'red light' failure with the surfaces frozen. No surge was treated as 'just one of those things', and much midnight oil was burned and hair pulled out (so that's what happened to mine ) to try and find the cause of the surge.
My friend EXWOK perfectly answered the intake hydraulics allocations.
EXWOK was right on the ball here as usual, in fact above Mach 1.6 an interactive surge was more or less guaranteed. The cause of interactive surge had nothing to do with the wing leading edge position, but to the radially generated distortion field coming out of the FRONT of the surging intake, severely distorting the adjascent intakes airflow. It mattered not if the originating surge was an inboard or an outboard intake, the other guy would always go also, above Mach 1.6.
You might want to take a look at 'When Intakes Go Wrong Part 1:
http://www.pprune.org/tech-log/42690...-thrust-5.html
and Parts 2 & 3:
http://www.pprune.org/tech-log/42690...-thrust-5.html
Not to mention Part 3:


dixi188
I can never recall this particular event happening with BA , certainly not as a result of a ramp failure. Although in the near 28 years of operation we had quite a few SNN diversions, none that I can ever recall were as the result of a ramp structural failure. The two major SNN diversions that I can recall were G-BOAF in the early 80s when an LP1 blade failed and resulted in a totally wrecked engine (although a completely contained failure) and G-BOAA in 1991, with another wrecked engine due to running in rotating stall. (Both of these events were covered previously in our thread). ChristiaanJ has mentioned quite rightly the event with A/C 001 spitting a ramp out, and Air France had a ramp failure going into JFK. (Covered previously in our thread, due to certain 'human foul ups'). I am not sure, but I think that this one in JFK DID require a double engine change in JFK. (Usually from SNN a BA aircraft would be 3 engine ferried back to LHR).

ChristiaanJ
Nope, you are quite right, no more French or British development aircraft ever suffered a ramp linkage failure again. The 001 ramp failure was a salutary lesson to the design team, and the intake assembly became tougher than old boots after that, nomatter WHAT you threw at it.


Due to the lateness of the hour (and me being up at 4 ), that will have to do for now guys.

Best regards to all
Dude

Howie the engine that you saw WAS the one removed from 001. Flight International said at the time 'Only an Olympus could swallow an intake ramp at Mach 1.9 and still run at 85% N2'

Best regards
Dude

dixi188
This incident could well have been G-BOAD #2 engine then; this one swallowed an intake ramp brake assembly. Details of this incident itself can be found in the links that I posted regarding 'When Intakes Go Wrong'

Regards
Dude .

I haven't worked out how to reply to postings and quote the relevant remarks yet - cut and paste doesn't seem to work, sorry.

Anyway, after that 1980 engine fire incident we did find a couple of small holes in the centrewall and as a result we fitted some ceramic coated steel plates in the vulnerable areas.

But as stated, the fire precautions built in did a good job. In this connection though it is worth saying that the cooling air passing over the engine comes from the ramp bleed in the intake and that it is controlled by 'secondary air doors' in the corners left between the circular engine and the square nacelle. These are there to stop air flowing back from the engine bay into the intake during takeoff and are opened once the pressure diferential between intake and engine bay is favourable. Part of the fire drill was to close these doors so the engine fire was deprived of oxygen, which helps a lot

CliveL

As with any aircraft the 71 was subject to any number of limitations, but airframe temperature was not one of them. The crew had no info on skin temp in any event. However compressor inlet temperature was the major limiting item (427\xb0C).

Thread on the Concorde inlets here http://www.pprune.org/tech-log/42690...ke-thrust.html

CliveL
First of all a hearty welcome from myself also to the thread, speaking as a fellow old Filtonian/Fairfordian. (I'm sure I must have bumped into you during my years at BAC Clive).
It is thanks to the tremendous skill and dedication of 'designer chaps', such as yourself and ChristiaanJ, that Concorde became this breathtakingly amazing aeroplane that she was. I can't wait to read some more of your informative posts; you obviously have one hell of a story to tell, and can obviously teach us all (especially me) a thing or three.
It was thanks to this superb system for sealing off the engine bay (as well as actuating closed the nacelle ground running flap) when the ESDH (fire handle) was pulled, that generally limited the damage caused by the engine bay fire you mentioned on G-BOAF in 1980 to the affected engine only. (Save as you say, those small holes in the centre wall). Also worth mentioning is the fact that extinguisher pressure would also trip a 'fire flap', that would isolate the ram airflow into the air conditioning heat exchangers, that were mounted directly above the engines.. In the case of the aforementioned incident, this was just as well, as both heat exchangers were seriously damaged by the fire, and another potential source of oxygen was fortunately removed. Yet another truly brilliant piece of design.

Best Regards
Dude