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Concorde question

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Concorde question

Old 21st Sep 2010, 10:23
  #441 (permalink)  
Join Date: Jan 2008
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As far as the cabin was concerned on state visits etc, it would be the main party (HRH ,PP, any other royals. PMs would have secretaries, PAs etc) and the rest of the entourage in the rear.

Royal flights always left from the Spellthorne Suite, not the main terminal! (You can imagine..."did you pack your bag yourself, ma'am?.."!)

Catering very different, with special meals/requests etc.

Security was very tight, dogs on board before boarding, (sniffer, not corgis!) armed police everywhere. Plain clothes chaps queing for cups of tea in the galley before the parties arrived... but everyone very professional and with a specific job to do. Just as you would expect, really.
LL x
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Old 21st Sep 2010, 14:39
  #442 (permalink)  
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Originally Posted by Nick Thomas View Post
I just wondered if there was any side slip problems etc due to the air flow being blocked to the vertical tail by the big delta wing especially at large AoA on landing? If so what was the undoubtably clever solution?
Hi Nick,
Your questions were already partly answered by NW1.
The solution was indeed in those two narrow strakes on the nose that generated a vortex on either side, the higher the AoA, the stronger.
Those two vortices "folded upwards", well before the leading edge of the wing, and around to the top of the fuselage, where they "stuck down" the air flow right to the end.
Hence the vertical tail was not "blanketed" by disturbed/turbulent air from the fuselage, and remained effective even at quite high angles of attack.

It was certainly a clever solution... but not new.
As stilton said, it was already used on the MD80.
On Concorde they had already been tested in the windtunnel and found to be effective, so if you look at photos of prototype 001 on its very first flight you will see they're already in place.

Vortices are funny things... usually you don't see them, but they contain quite a lot of energy and persist for quite a long time before dissipating. That's why those two small planks on Concorde work so well.

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Old 21st Sep 2010, 17:06
  #443 (permalink)  
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For Mike_Bracknell

The rudder failures weren't really down to a fault with the original design, here's the story as I remember it:

The ctrl surfaces are made of a honeycomb-core bonded to the skins, essentially. They originally had a blunt trailing-edge, as was then de-rigeur with supersonic design. At some stage it was decided that a sharp trailing edge was actually beneficial so they had an extension fitted, which had the unfortunate effect of allowing a certain amount of water ingress to the core. Heating and expansion of this lead to disbonding and ultimately failure of the surfaces. (I suspect my engineering colleagues will have a much better and more accurate explanation).

Now - here's the important bit, and another example of this aeroplane's excellent failsafe engineering; Concorde had two rudders, one above the other (same as the 747). Each is driven by one dual-bodied PFCU. You ABSOLUTELY don't want a PFCU endangered by ctrl surface damage so each surface is divided in two, either side of the PFCU control horn.

Visualise the PFCU attached to the centre of two surfaces with an end rib on each, but skinned to look like one surface. Therefore, in the case of the surface suffering damage, it can only spread to a point short of the all-important PFCU. Look at the rudder-failure pictures and you'll see what I mean.

So - far from the 'rudder' breaking up, the reality is that half of one of the rudders had failed.

It was somewhat inevitable that Concorde's control sfcs would suffer, given the horrific loads they endured, and this was dealt with at the design stage. The elevons had the same sort of design.

It does of course look bad when you land with bits missing and this, plus the Regulators and company safety depts ensured that eventually some HUGELY expensive replacements were built.
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Old 21st Sep 2010, 17:38
  #444 (permalink)  
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Yet another question and again this concerns the AofA on landing. As she slowed down the drag must have increased so would more power be required to fly slower? If that was the case was a higher speed kept on approach to save fuel, engine wear and also to reduce noise? As SLF I apologise for asking what may be simple and obvious questions to all you Concorde experts.
Thanks again

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Old 21st Sep 2010, 18:08
  #445 (permalink)  
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Originally Posted by Nick Thomas
Yet another question and again this concerns the AofA on landing. As she slowed down the drag must have increased so would more power be required to fly slower? If that was the case was a higher speed kept on approach to save fuel, engine wear and also to reduce noise? As SLF I apologise for asking what may be simple and obvious questions to all you Concorde experts.
Thanks again

Correct, Nick. More power was needed to fly the ILS at 160kts than at 190kts. So they kept 190kts and reduced to Vref+7 at 800 ft, IIRC (somebody wrote about it on the previous pages).
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Old 22nd Sep 2010, 03:03
  #446 (permalink)  
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Had a chance to go on the BA Concorde, due to the fact that BA certainly realized the allure the Lady had on all pilots, but sadly, my friend who was suppose to join me got sick, so we rescheduled for another flight at a later date. Well, the tragic events of Air France never gave us the chance.

Having spent the last 11 years based JFK, it never got old to see this magnificient bird arrive and I think to a man, or woman, every one always took a moment to look.

Anyway, found this video on youtube, one amongst very many, however, she was most photogenic, so not much to argue about there. Imagine a few of the posters here had a hand in this:

YouTube - Concorde formation
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Old 22nd Sep 2010, 22:54
  #447 (permalink)  
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You had to stop and look.

Having spent the last 11 years based JFK, it never got old to see this magnificient bird arrive and I think to a man, or woman, every one always took a moment to look.
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.

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Old 22nd Sep 2010, 23:58
  #448 (permalink)  
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Another rather Cron mundane question I'm afraid.

Looking at the many available pictures of the Concorde cockpit, the question of access to the pilots' positions is of interest. It appears to a laymen, such as myself, that an orchestrated position take up would be required, perhaps pilot 1, then pilot 2, then engineer to avoid clambering over each other.

Upon reaching their position, the pilots must have executed some - can I say undignified - legovers and manoeuvering to seat themselves.

I'm imagining a scenario of highly qualified and (perhaps) highly paid skilled aviators with legs at strange angles grunting and twisting themselves into the most advanced aircraft in the World.

Whilst this is happening the Engineer, inwardly laughing to himself, occupies his spacious workplace.

I'm sure I am quite wrong in my visualisation but it would be interesting to hear how the Concorde cockpit layout compared to other types.

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Old 23rd Sep 2010, 00:20
  #449 (permalink)  
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Hi again
I think the management of fuel on Concorde is fascinating.One of the reasons that this thread has been so interesting to me has been the explanations on how the fuel not only provided a potential energy source but was also used as a cooling medium and especially it's use in moving the CofG.
Am not sure but I think that some baggage was stored aft of the cabin. If that was the case on landing was fuel pumped forward to balance this out? If that was so when deciding on the amount of fuel needed plus diversion fuel etc was there a minimum amount of fuel that had to still be in the tanks on landing?

Last edited by Nick Thomas; 23rd Sep 2010 at 01:44.
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Old 23rd Sep 2010, 01:10
  #450 (permalink)  
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That's why those two small planks on Concorde work so well.

Quite a common trick of the trade eg with fighters eg the leading edge extension (LEX - the narrow aspect delta at the front of the wing) on the F18 and others. There are plenty of pix around with the vortex made visual due humidity and it can be seen to be tight, curly and designed nicely to interact with the fins - which, for the F18 has caused much in the way of fatigue related grey hairs in the boffin fraternity.

and especially it's used in moving the CofG.

again, a common observation eg 747-400 tail tanks .. just a matter of how much the movement is required to be.
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Old 23rd Sep 2010, 01:50
  #451 (permalink)  
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I agree that the 747-400 had tail tanks but the 747 upgrade was approx 20 years after Concorde first flew!

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Old 23rd Sep 2010, 06:32
  #452 (permalink)  
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Cron -

One of the downsides to flying a pointy aeroplane is that the front is somewhat narrow, as you have identified. It wasn't too bad getting in and out, but it was easier for the pilots to get in before the FE was in situ.

Once in, it was fine. The roof and especially the side window was much closer than one finds in other types, but there was adequate space. It helped to be less than 6' tall (I'm not.....)

As for the engineer's space being 'spacious', well that's relative. It was a bigger space than the pilots'; however a few of the FEs were quite.....spacious.......themselves so they had the same problems as us.

Nick Thomas -

There were, as you say, baggage holds under the cabin at the front, and one aft of the cabin (the bigger one).

One would try to distribute the load to minimise any pre-take off fuel txfr, and especially to minimise any burn reqd (we're getting into a new subject here....).

Having done this one knew the empty CG and then managed the fuel accordingly. Min reserve fuel was 6500kgs and that was more than enough to manage landing and taxying CG. After landing a chunk of fuel was pumped forward for taxying purposes and there would always be ample for this unless one was seriously low on fuel (low enough for a 'Mayday' to be mandatory rather than just a bit tight).
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Old 23rd Sep 2010, 07:33
  #453 (permalink)  
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Was all initial training accomplished in the sim or did new "to type" pilots do touch-and - goes before flying the line? How long was the conversion course? I imagine it was quite thorough.

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Old 23rd Sep 2010, 07:48
  #454 (permalink)  
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It was a loooong course!

In essence -

6 weeks groundschool, then type technical exam
Long sim course (lots to learn!)
Base flying
The usual SEP days
20 sectors of line training

In total - a shade under 6 months beginning to end.

You had to do a couple of months online before being released to charter flying and lightweight take-offs.

The sim was great, but couldn't quite replicate the unusual handling in the flare so, yes, we did circuits.

More fun it is almost impossible to have in a commercial jet!

It was, of course, eye-wateringly expensive in fuel, tyres and engineering time which was why one had to commit to a large number of years on type if one got a course.

And it was worth every second.
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Old 23rd Sep 2010, 15:05
  #455 (permalink)  
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FSLabs - Concorde-X simulation for FSX

Update: This reply was not intended to be posted publicly, as it was directed to select few individuals. We will, however, honor all requests sent to Flight Sim Labs, Ltd. until 30 September, 2010. Apologies for the inconvenience!

Gents (and Landlady!),

I am ashamed to admit that I only now discovered this wonderful thread regarding the best aircraft that ever was.

I've chatted with some of the great minds behind the development of the actual aircraft and I've felt very proud that a select few (ChristiaanJ and others) have helped my team with invaluable insight as we developed the Concorde-X addon product for Flight Simulator X. (We only hope we did "her/him" a bit of justice with our final result).

In recognition of all your efforts, I'd like to offer everyone who has been involved in the development and/or flying of the real aircraft a free download copy of our product, if only as a token gift which might bring back some memories of what it felt to be inside its Flight Deck and cabin. Just write our support team (support (at) flightsimlabs (dot) com) a small note (please give us some info on the nature of your relationship with the bird) and we'll provide you with the information required for the download.

Please keep those memories coming - they are the best way to keep the legacy going!

Lefteris Kalamaras
Flight Sim Labs, Ltd.
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Old 23rd Sep 2010, 16:20
  #456 (permalink)  
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Just because I am so curious, what speed and profile would be used when flying the circuit? I came across a figure somewhere saying minimum V2+50 (with 250 kts suggested); was that maintained all the way to final, and did that not make for some very large circuits?

Rather amazing that the circuit speed of the Concorde would be more than twice the cruise speed of what I fly...

And also, could the Concorde handle something like, say, a destination where the only instrument approach would be a full procedure non-precision approach with a 185 kt max base turn? Or a SID where the initial turn would be made 10 miles out at maximum 210 kt?

Trivia questions, I know, but this plane and everything about it is just so fascinating!
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Old 23rd Sep 2010, 22:10
  #457 (permalink)  
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Really interesting thread - thanks to all those who flew/worked on/maintained her. One thing that has bemused me for about 15 years - I took a picture of AC parked at JFK about sunset and its adjacent to an airbridge but parked nose out and not 'plugged in' for people to access - was this a one off or the normal way to leave her for overnight parking?
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Old 23rd Sep 2010, 23:44
  #458 (permalink)  
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Circuits: for bjornhall

You're about right with the downwind speed - 250kts was standard.

Speed would be reduced to 190kts at the end of the leg, and then back to final speed on final approach.

Final speed would be one of the following:

Vref (not that often used, and not the nicest speed)
Vref+5 (one engine out)
Vref+7 (at the end of a fuel-saving ILS approach. Nicer to land off than Vref and the most common speed)
Vref+10 (as above in winds above 25kts?? Minimal flare off this one)

Round about the 155-165kt mark in normal ops.

Health warning - all the above from memory, NW1 will correct me if I'm wrong. (My manuals are stashed in the loft).

The pattern was flown at 250kts and 1500ft. The trouble is, you lift off at 210ish kts, not climbing that fast as you're way down the drag curve. Over the next thousand feet you steadily accelerate, and at the same time the RoC goes waaaay up as the drag reduces. This is fine - so long as you spot it and deal with it pronto.

It was quite easy to find oneself at 1000' flying at, say, 260kts. So you raise the nose a bit, to find you're still just creeping above 260kts passing 1300' (drag still reducing)....... and climbing at 5000fpm. And accelerating.

I'm told the record was 300kts and 3000' and I believe it!

Luckily we arrived on the scene armed with this story. I have to say the first thing I did passing 800' was roll on 30 degs of bank which calmed things down nicely.

Awesome fun.
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Old 23rd Sep 2010, 23:51
  #459 (permalink)  
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Sorry - missed the second half of your question.

We didn't have any trouble flying procedures drawn at 185kts. If necessary you could fly and manoeuvre at 190kts IAS, it was just very thirsty and noisy like that. We wouldn't manage 10miles out at 210kts on a SID, but I didn't ever encounter a SID like that. In the case of terrain-constrained ops (which may cause the above) we would have to come up with some usable aternative.

The 'tightest' destination I recall was Sondrestrom (as it was still called then). Although noone in their right mind would land a heavy on RW28 (as it was) we had to demonstrate it in the sim. It really wasn't an issue in terms of turn radius, the trouble was the radalt ramping caused by terrain combined with our higher speed. It was just possible to avoid the dreaded GPWS.

Of course when you took the real thing there we just landed staright in on 10.
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Old 23rd Sep 2010, 23:56
  #460 (permalink)  
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Yep,that sounds about right - no reason to leave easy access to an aeroplane you don't want anybody on board.
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