Posts by user "Landroger" [Posts: 38 Total up-votes: 0 Page: 1 of 2]¶

First of all, many, many thanks to our four main sources of Concorde 'nectar'; M2Dude, ChristiaanJ, Bellerophon and Exwok. Their input, each from a slightly different viewpoint, is absolutely captivating. As fascinating as the lady herself.

Christiaan rang an awful lot of bells with his description of some of the electronics - it was very, very similar to the stuff I used to work on, back in the early days of production CT Scanners. Cut tracks and wire links were the 'staff of life' and the stuff of nightmare. Our first minicomputers - to reconstruct the CT image - had 32 kilobytes of memory on four boards, each about 17" square!! My phone has about 2 Gigabytes of memory! Now this was in the late seventies, when Concorde had been flying for a good number of years.

My question, which is a bit of a tilt at windmills, is this; If you had to build Concorde all over again with the same airframe and engines, how much more room, how much lighter and how much more capable would the electronics be if they were made using the latest surface mount, Extremely High Density integrated circuits and microprocessors?

Thanks again everyone, for the best thread I have read on PPRuNe for two years (and there have been some superb ones in that time )

Roger.

Thanks for the detailed replies guys, which pretty much chime with some of what I'd guessed, although it is clear I had 'overestimated' the technology available to you at that time. There was me talking kilo bytes and you only had kilo bits to work with!

Your photograph really brings it home Christiaan. What little horrors hid inside those TO5 cans? Apart from the fact that your board must be brand new - the track cutters and wire linkers hadn't got at it yet! What is interesting are the connections - only eight pins, as far as I can tell? We had 15/25/60 pin 'D' connectors or multi path, gold 'edge' connectors at least.

I wasn't quite clear what you meant here Christiaan, 1% of what? Because Dude is talking about serious weight and space saving - which I would expect.

We can, indeed dream Dude - I envy you both, your involvement with such a fabulous (in its truest sense) project.

Roger.

Ah now, those boards are actually very good looking boards. I particularly like the PROM board and although I know about the programming of those, it is only at third hand. I certainly had to install many of those PROMS that had been specially 'burned' in Milwaukee, to overcome a particular problem.

I'm a bit embarrassed about missing that multi pin socket on the AICU board. I somehow thought it was a specific function chip or a development test socket. Some of those used to appear and remained on some of our boards.

I'm not surprised about the massive cost of replacing certain boards in the later years. Some of those components would have been made of unobtainium long before the millenium. And I just noticed DozyWannabe's question about core memory. I guess it would have been core, because the 8Kb memory boards I spoke about, from the early CT Scanners, were Data General core memory, with a cycle time of 800usec. Although with four way interleaving, we could get that down to the read cycle time of 200usec!!

I freely admit I am staggered at how capable were Concorde's electronics - indeed how capable was the whole aeroplane - despite their rather ..... fundamental nature. My respect for everyone involved in the project increases with every post to this thread.

Roger.

One of my Scout Leaders, back in the sixties, was involved in (I think) programming the milling machines that milled Concorde wing panels from solid alloy billets. Dural I assume, I didn't think there was much Titanium in Concorde?

How much of the Lady's structure was machined from the solid like this? In one sense, it seems extremely wasteful, but in another it is the most perfect way of "knocking off everything that doesn't look like a wing panel." To paraphrase someone.

Roger.

I would venture to suggest Dude, that what you describe pretty much holds true with any complex system. While I hesitate to anthropomorphise such systems, I know from my own experience with MRI/CT systems that the hard worked ones are the most reliable.

Indeed, the ones that are worked way beyond what is 'reasonable' - and some are truly 'hammered' - tend to break down more than the 'hard worked'. At the other end of the scale, the lightly or intermittently used systems definitely break down more than the 'hard worked' norm. And don't leave a system unused for any length of time - a week or so will do it - and don't even think about turning it off at the A1 breaker!

While we are at it, there is also the 'sympathetic brain waves' syndrome, a theory a much missed, late engineer friend of mine in the past had. As the amount of current required to consider a junction 'switched' went down and down, the closer it got to the amount of current/ion exchange necessary to 'fire' brain synapses. Stay with me - I more than half believed this!

Neil theorised that as the users - radiographers - got more stressed by patients, doctors and life in general, the more their synapses transmitted some sort of negative signal to the equipment - and it broke down. When I, or one of my engineer colleagues arrived on site, our more sympathetic 'engineer vibe' synapses did what our hands would have done and 'fixed it'. As a result, we rarely ever saw evidence of the weirder problems the user reported.

So, while Concorde clearly 'enjoyed' doing her job, did she respond to your obviously sympathetic synapses?

Roger.

Diesel8 made this observation which, given he/she was in New York, was hardly surprising that people stopped to look. I live in south London under an area where aircraft are not far from acquiring the glide slope for 27L or departing from 10R, so aeroplanes are a part of everyday life. Having said that, they're not at the moment because of the runway work! But I digress.

I have loved aeroplanes since I was very young - I genuinely understood Bernouli's principle when I was about nine - and I always looked at aeroplanes, indeed I still do. But most of the time, when the engine note was obviously a 747 or 727 (noisey!) or some such, I would perhaps concentrate on what I was supposed to be doing. But in the early evening, the absolutely inimitable sound of 593s would draw the eyes of nearly everyone in our area. We saw her every day and yet we all looked. Always. Extraordinary.

Not being in the flying profession, I only have two Concorde stories of my own. Back before the M25 was completed and it stopped at Poyle, I would take the opportunity to use what became the Poyle northbound on ramp as a 'plane spotters' place. One evening I stopped in the gathering dusk and got out to watch a few planes. 737s and 757s abounded as the light faded, leaving a broad, light blue band across the horizon, tinged with peach and little colour anywhere else.

Then I heard her on her way and the old heart beat a bit quicker. Suddenly she was up and passing and my mind's eye took the photograph I always wanted and now will never get. Concorde, silhouetted against the horizon, the cabin lights just visible, but the four, electric blue reheat exhausts - including shock diamonds - the only other colour in the monochrome image. Unforgettable.

The second was day time. I was parking my car in the north car park - when it was basically all the way down one side of 27R. On my way, I think, to Stockholm Arlander, I was ignoring the succession of 'light iron' going by very close. Again, I heard her light up and just stood and waited. Fabulous sight of Concorde, just rotating as she passed me and climbing away to the west trailing thunder ..... and every car in the north car park sounding their tribute when the reheat set off their alarms.

You just had to look - every time.

Roger.

Seconded Landlady, but the traditional; 'Many Happy Returns' is sadly no longer possible. Also, its quite extraordinary that more than forty years have passed since that date - that's a whole grown up person!

Perhaps 'Happy Anniversary' to all the thousands of people who made Concorde what she is, would be more appropriate?

Roger.

All this talk of a 'B' model is both interesting and a bit frustrating. It must be all the more so for our main contributors - M2Dude and ChristiaanJ - and I guess the crews themselves, that the 'B' never saw the light of day. The discussion about the engines/ intakes/ nozzles is taking place about another flight level above my head but still riveting stuff nonetheless.

May I ask a question about another aspect of Concorde life? In my own job as a CT/MRI scanner engineer, I was for many years a 'Registered Radiation Worker' and indeed I still wear the equivalent of a film badge. My annual dose though was and is tiny, virtually background. However, I remember seeing a chart from the Radiological Protection Board some years ago, that seemed to suggest Concorde Crews had the highest radiation dose in any industry routine operations.

Was this true and did Concorde crews wear a film badge as I did? I understand that 'ordinary' flight crews get quite a radiation dose, but nothing like the 60,000ft doses the lady permitted?

Roger.

I'll certainly look out for one Christiaan, but the hospital where I remember seeing it has been closed for seven years and I noticed the developers had moved in the other day!

Out of pure, vulgar interest in my field, the hospital was Atkinson Morley's Hospital in Wimbledon. This hospital is where Stirling Moss did much of his rehabilitation after his near fatal crash and huge numbers of patients benefited from pioneering neurosurgery . Most importantly from my point of view, AMH where the original prototype CT (Computed Tomography) scanner was installed and all the early clinical work - done by Doctor James Ambrose - was done. This machine is the one that can be seen in the Welcome Medical Gallery in the Science Museum and I used to work on it!

Roger.

I've just started reading Genesis of the Jet , by John Golley again - for the third time. I'm sure you know it's about Sir Frank Whittle and the birth of the jet engine. In the introduction there is an account of a Concorde flight to Washington, that carried Sir Frank at the age of about 76. It concludes;

'After they landed at Dulles International Airport outside Washington, Captain Monty Burton addressed his passengers;
"Ladies and gentlemen, welcome to Washington on this fine afternoon. We have covered the 3900 miles from London to Washington in 3 hours 37 minutes, giving us an average speed of well over 1000 miles per hour. The maximum speed we achieved was 1340 miles per hour and our maximum height was 60,000ft, eleven miles above the surface of the Earth.

Today we have the great hour of carrying Sir Frank Whittle who invented the jet engine which made all this possible." There was a great round of applause and a bit of cheering, which was most unusual from Concorde passengers. When Monty Burton left the aircraft, an American passenger came up to him and said; "You know Captain, you've really put the icing on the cake for me. To travel on Concorde as a fellow passenger with Sir Frank Whittle is something I can relate to my grandchildren!"

Great book by the way.

Roger.

Sorry Dude, I'm behind on this again. I must be in the hard of thinking class on this. Would you just confirm - or jump all over - what I am visualising here please?

Due to some quite esoteric disturbance in the area where fuel first hits compressed air, the flame front either detaches from the nozzles or establishes some way downstream? As far, indeed, as the turbines with a very hot (too lean?) mixture that damages the blades? Is that anywhere on the right track?

The closest analogy I can think off is with a plumbers blow torch, where the fuel pressure/temperature is disturbed while lighting it. The flame detaches from the burner and exists - usually briefly - up to an inch from where it ought to be, often with a very harsh, high pitched roar. I've seen it happen with my oxy/acetylene torch on light up as well, but only briefly and it usually goes out.

Roger.

M2Dude wrote:

You'd have to say that designing and building the aeroplane probably isn't the tough issue. I mean you could probably adapt a military design - a Tornado can lift more than six tons of stores can it not? So that's a ton of people, a ton of bling to keep them comfortable and four tons of fuel ...... oh.

The tough thing needed, the really clever thing that Concorde did and no other aeroplane, sorry, only one other aeroplane - our 'honorary Concorde' the SR71 - would be to design the engine /intake /nozzle configuration that would let our 'Tonkorde' supercruise at Mach two, while running on the smell of the stuff.

Roger.

Sorry Dude, didn't realise that use of the 'T' word would upset you so! Perhaps you were frightened by one when you were a baby? I picked the T*****o randomly to illustrate the contrast between a military supersonic design and Concorde. She really wasn't a converted bomber and even by using up every ounce of a Tonka's lifting capacity, it would still run out of fuel before it reached the Fastnet Rocks, let alone anywhere useful.

I must have missed something about the SR71 while we were discussing 'Inlet Thrust' on the other thread. I thought there was at least some part of the performance envelope where the Blackbird 'supercruised?' If not, then Concorde's ability in this area is all the more astonishing.

While mentioning the SR71, a striking image of them - to me anyway - was of the streams of fuel, leaking from every seam of the fuselage immediately following in-flight refuelling. These apparently 'sealed up' when she expanded in supersonic flight. How did Concorde avoid this rather startling phenomenon?

Roger.

It is still difficult to grasp the fact that, with the one exception Christiaan has told us about, all of the control electronics in Concorde were analogue. Some of the little tweaks Dude has just alluded to in his reply about the nozzles and the relationship of compressor speeds, for example. Most of them would be relatively easy - relative is a huge word of course - if they were microprocessor controlled locally and sending/ receiving status and demand data to a bank of central computers. But to do it with analogue signals and controllers is mind boggling.

How all these signals and rates were calibrated and stayed calibrated is a mystery. The earliest scanners I worked on - mid seventies - were largely digital even then, but they did have quite big chunks of analogue circuitry. Virtually every process had to be self calibrating, most of them at the start of every scan. Even then drift was often a problem and sometimes problems would arise where drift exceeded the authority of the self calibration to manage it.

These pages of Concorde information are incredibly interesting, with more and more eyebrow raising revelations with each page. I still think that the nicest observation made was by Galaxy Flyer - an American, when many of his compatriots tend to the 'not invented here' school of appreciation.

And to compare Concorde with say the Apollo Project which inspired many a UK engineer, is praise indeed.

Roger.

You're right there GF - the AVRoe Arrow is a complete mystery to me and I've heard of the Martin Baker single seat fighters and the Percival Peregrin!

Roger.

A couple of observations and a questionette, if I may? First, I'm feeling quite pleased with myself that I have largely understood the latest phases of discussion, re: Reheat Ignition and N1 resonance! To be fair I was a bit puzzled about 'Hot Streak' until Dude explained in a slightly different way. Then my first thought was; 'Cor crikey, isn't there enough heat on the turbine blades already?' It seems not, but it does raise the issue of TBE (TEB?) injection, a la SR71? I know the Blackbird used rather different fuel (JP8?), but is there not a similar chemical that would have done the same thing? Perhaps it was a reluctance to use 'exotic' chemicals in a civilian aeroplane?

The resonance issue is quite interesting, in that it appears to have affected all models of Olympus and was at roughly the same rpm on all. I take it that any attempt to damp specific frequency resonance would have adversely affected the performance?

Which brings me to my questionette - given that Bristol-Siddley created the original design when jet travel was still quite novel, what was it about the Olympus that made it so capable in so many guises and for so long? Not only Concorde of course, but TSR2, warships and fixed electrical generators.

Roger.

M2Dude wrote:

I haven't needed to read a diagram like that in .... a whole grown up persons lifetime! AND gates and OR gates, 'Op Amps' and an Exclusive OR, if I'm not mistaken?

Thanks Dude, that really puts texture to cold facts. While you are all taking the trouble to explain a hundred small elements of Concorde's make up, I'm sure many of the readers hooked on this thread will be blinking back tears of insipient brain damage at some of the control logic you have all spoken about.

Certainly it sounds, from time to time, that there were a million little black boxes dotted all over her airframe. I suspect however, that many of the 'terms' and 'laws' spoken about are simply a gate or two, perhaps an op' amp, placed in a larger circuit that modulates the output of that board, thus creating the law or term.

I know you have answered my original question about calibrating all these circuits, but nothing I've seen here yet has reduced my frank admiration for the guys (and girls?) who designed the electronics for Concorde. It required true creativity and instinctive engineering that I doubt still exists. Digital control is a hell of a lot easier than Analogue - in my humble opinion.

Seasons greetings to everyone on this thread, especially to our (growing - welcome Clive ) band of Concorde experts.

Roger.

Okay, for the benefit of all the SLF and Vulgar Curiosity Seekers watching this thread, I will ask the 'nice but dim' question.

I thought I knew a bit about aeroplanes, but M2Dude, CJ and now Clive are pushing my knowledge and understanding to their limits. I see them on Clive's two fabulous images and I've heard some of the pilots - Exwok and Bellerophon - talk of it, but up to now it was something I could take for granted and move on. Now I have to come clean and ask. Vortex lift for dummies please gentlemen?

The end on view is very dramatic and I can only surmise the rotor of air above the wing somehow accelerates it to reduce its density still further, thus generating lift. More lift indeed than the cord profile can provide without creating too much drag. Close? Or wooden spoon for Rog?

Roger.

Thank you CJ, this too adds texture to bare fact.

This will be interesting, I shall look forward to that.

I'll admit I was still a bit doubtful, until you wrote this, particularly:-
and I say Amen to that! Modern software, at least the stuff that drives my kit, comes delivered with bugs and very often the 'workaround list', until that is superseded by an even longer list.

The software on the original EMIScanners was written in BASIC and was amazingly efficient as well as being surprisingly bug free and 'bomb proof'. Of course it wasn't very quick and it was possible to figure out almost exactly what was happening at any given millisecond.

Modern software - on our kit anyway - is doing fifteen things at once while processing huge dollops of data - much of it computational - and no-one, not even the software writers, can tell you anything more than approximately what is happening at any time.

I think, perhaps, my respect for the analogue designers comes from my relative weakness on the core electronics. I've been a 'System Engineer' for too long and some days I never even get a screwdriver out.

Looking forward to more guys.

Roger.

Yes, I think it does Clive, although if I may summarise what I understand, perhaps you can correct me? The vortex in 'vortex lift' is triggered by the profile of the leading edge, both its plan and section, at increasing angles of attack. In level, supersonic, flight the vortex does not exist and all lift is generated 'conventionally' by the aerofoil section of the wing.

As the AoA increases when Concorde slows down, the vortex comes into being and becomes stronger as the angle increases, creating a low pressure tube into which the wing is 'sucked upwards' - vis vortex lift. How did I do?

Somewhere between where you are catching up on this thread Clive, and this point, M2Dude posted a lovely story about Dr. Ted Talbot, lamp black, diesel oil and the American B1A bomber. I can't find the post number, but you will eventually stumble upon it and doubtless smile, as I did.

Thanks for the explanation - it was less painful than I had feared.

Roger.