Posts by user "Nick Thomas" [Posts: 53 Total up-votes: 0 Page: 1 of 3]ΒΆ

Nick Thomas
August 19, 2010, 12:24:00 GMT
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Post: 5879895
Expansion

As I understand it due to friction heat caused by flying at mach 2 Concorde would expand by approx 6 inches. Some of this expansion could be seen between the FE panel and flight deck partition. Obivously the interior would be at a comfortable temp of say 21c; thus the exterior would expand but the interior linings etc would not. So finally to my question- How was this differential expansion delt with? I have really enjoyed reading the clear answers posted answering many interesting Concorde questions.

Last edited by Nick Thomas; 19th August 2010 at 12:26 . Reason: Clarity

Subjects: None

Nick Thomas
August 20, 2010, 00:49:00 GMT
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Post: 5881047
Thanks for your answer CJ. There must have been some flexibilty built in around the window openings other wise the window openings near the fixed point would show less movement than the ones at the other end which would show 3 to 4 inches difference between the inside panel and the actual window. I guess all the hydraulic and fuel lines must have had some "slack" to allow for expansion.

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Hydraulic

Nick Thomas
August 20, 2010, 12:56:00 GMT
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Post: 5882095
Once again thanks M2dude and ChristiaanJ for such interesting answers. Whilst Concorde was not a commerical success it was certainly a technical "tour de force". Would it be too much of an exaggeration to say that Concorde provided the sound technical foundations on which Airbus have now so successfully built?
Am I right in saying that Concorde was the first fly by wire commerical plane?

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Airbus

Nick Thomas
August 20, 2010, 16:58:00 GMT
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Post: 5882567
Thanks M2dude.
I agree that Concorde was a commerical success especially for BA. Unfortunatly due to outside factors ie cost of fuel etc; it never had a chance to sell in sufficent numbers.
I wonder if it had been an american product if it would have sold more? Ideal speculation maybe!
What is certain is that everyone involved in designing,maintaining and operating her has every reason to be proud of their contribution to aviation.

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): British Airways

Nick Thomas
August 21, 2010, 17:52:00 GMT
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Post: 5884403
Well said Biggles 78. It's not just the technical know how of CJ and M2dude that is so impressive; it's also the clear way that they explain everything.
If an engine had a fire or an explosive failure; it would seem on the face of it that the adjacent engine could easily be affected. As everything on Concorde has a sound technical reason. I have been wondering what that reason or reasons was? and also if there was any inbuilt dividing protection between engines on the same wing?
Not being an expert on jet engines (or any aviation matter), I was wondering am I right to assume that as air pressure decreases with altitude then the amount of thrust needed to maintain M2 would also decrease? This would explain the reduced fuel consumption at higher altitudes.
Would I also be right to assume that the max power delivered by the engines would reduce at altitude, thus even if the engines were run at near to available max power at high altitude it would be no way near the max power at lower levels? The reason I ask this is that I started to think that if the engines were being run at near to max output then the life of the engines would be compromised. Yet if what I have said above is true this would not be the case?
My other query concerns the FE. I understand that he set take off power etc and I can understand that it would be difficult for the pilots to do this at a time of heavy workload. I also understand that he also checked the pilots inputs into the INS system. So was he/she also a qualified pilot?
Once again many thanks

Last edited by Nick Thomas; 21st August 2010 at 17:54 . Reason: Ad a question mark

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): INS (Inertial Navigation System)

Nick Thomas
August 22, 2010, 18:35:00 GMT
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Post: 5886043
I have yet another couple of questions and I hope all you Concorde experts don't mind me taking up your valuable time.
As regards fuel burn: was there any difference between each indvidual airframe and if so was it significant enough to be considered when calculating the trip fuel? Also did different engines also have slightly different fuel consumption?
Whilst on the subject of engines, I just wondered how many were required to keep the BA Concorde fleet flying? What sort of useful life could be expected from the engines?

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): British Airways

Nick Thomas
August 23, 2010, 13:03:00 GMT
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Post: 5887472
On the ITVV Concorde DVD the Captain explains that during the cruise climb at mach 2 the auto throttles were armed and would be used as required. Then during descent the throttles were gradually pulled back whilst the autopilot was given an IAS of I think 350 knots. Therefore the plane would have to descend to maintain that speed. He explained that the power settings were chosen to ensure that there was sufficent cooling etc.
My query is if an autoland was to be undertaken was the auto throttle system able to maintain the required landing speed or would the pilot have to manage the throttles? I guess that decreasing or increasing the pitch to control speed when on the glide slope would not be a good idea.
Thanks again
Nick


Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Auto-land  Auto-pilot  Captains  Glide  IAS (Indicated Air Speed)  Intelligent Television and Video

Nick Thomas
August 24, 2010, 17:13:00 GMT
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Post: 5889890
As Concorde was in reality the first and only successful SST; a lot of useful information must have been gained during the flight testing phase. Were there any plans to incorporate any updates/modifications based on leasons learnt into later production models(if there of course had been more orders)?
Whilst typing the above I was reminded of something I read many years ago; that MI6 managed to pass slightly doctored "blueprints" to the Russians and that was the reason that "Concordski" was such a failure. I have always assumed that this was an "urban myth".
Regards
Nick

Subjects: None

Nick Thomas
August 25, 2010, 12:23:00 GMT
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Post: 5891412
Going back to my earlier question regarding expansion of the airframe. I have noticed that the BA Concorde paint scheme was slightly different to the rest of the fleet. All other BA aircraft have blue paintwork to the lower third of the fusalage yet all of the Concorde fuselage was painted white. Was this to reflect heat or just a marketing ploy? I have always presumed it was the former.
Thanks
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): British Airways

Nick Thomas
August 25, 2010, 17:39:00 GMT
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Post: 5892059
Thanks M2dude and all other aviation professionals for making us "normal" posters so welcome on this thread.
Being a child of the sixties I clearly remember the feeling that we were at the dawn of a new technological age and Concorde and the Apollo project were the outstanding examples of what was possible. Great times.
Am not a computer expert but I have always wondered if the limitations of the 60's hardware meant that the software had to be more elegantly desgined than now?
Having watched the ITVV Concorde DVD, Captain David Rowlands and SEO Roger Bricknell come over as very knowlegable and friendly people. I hope they are both enjoying their retirement.
Thanks again
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Captains  Intelligent Television and Video

Nick Thomas
August 26, 2010, 11:43:00 GMT
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Post: 5893615
Going back to expansion and paint. With the aircraft expanding approx 6 inches and a temp change up to 127`c, I guess a special kind of paint; able to withstand such adverse conditions; must have been used? When deciding on the paint specification was any consideration given to the overall weight of the paint?
Did the repeated expansion and contraction cycle have a detremental effect on the ulitamate life of the airframe?
I read somewhere that on the last supersonic flight of each BA Concorde, the flight engineer placed his cap into the gap between his panel and the cockpit bulkhead thus leaving it there for ever more. A nice story if true.
Once again thanks
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): British Airways

Nick Thomas
August 27, 2010, 11:56:00 GMT
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Post: 5895972
I understand that before the first flights the test pilots had many sessions in the Concorde simulator. I have always wondered how before the first flight they decided to programme the flight enverlope into the simulator; especially as Concorde was so different to other jet transports?
I guess that as more information was gained during flight testing; that this was programmed into the simulator and therefore made it a more suitable machine for airline crew training.
Thanks
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Concorde Simulator  Simulator

Nick Thomas
August 29, 2010, 17:57:00 GMT
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Post: 5900319
I know that other planes such as the 747 had INS; so in a way this question is not specifically related to Concorde. With the radio navigation update was the lat and long of appropiate radio beacons hard wired into the system and then based on the assumed position the nearest beacons would automatically be tuned or did the pilots enter the lat and long of the beacons that they would then manually tune?
I guess there were three INS units to allow for drift etc and it would be easier to spot if one unit was less accurate than the other two. So when radio updating was not possible ie over the atlantic was it possible for the automatics to weigh against one rouge reading
Finally as Concordes ground speed was over double that of other aeroplanes was there any need to take this into account when designing and building the INS system(other than the speed display that would have to show an extra digit)?
Thanks
Nick

Last edited by Nick Thomas; 29th August 2010 at 18:00 . Reason: punctuation

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): INS (Inertial Navigation System)

Nick Thomas
August 29, 2010, 22:59:00 GMT
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Post: 5900754
Thanks for your comment M2dude, am just SLF with an interest in design, due to being a member of the profession accused by the Prince of Wales "of doing more damage to this country than the Luftwaffe"!
This may seem a trival question but on the ITVV video Capt Rowlands is checking the pitch trim and the sound made is as he says "rather like a french bicycle bell" and he suggests that it may indeed be made by such a bell. I rather like that idea; but was it so?
I remember in the early eighties loading programmes into my ZX81 using cassettes; and not having much success! Mind you a cassette tape would be far better than an 8 track as an 8 track would keep reloading the route and you would end up flying in circles!
There is a serious point here and that is if you are designing such a complex machine as Concorde, if you can use proven technology in some areas then do so. It appears that all the people involved did so and didn't waste time on "reinventing the wheel" or complicating things just for the sake of it. Good design is about finding the most appropiate solution and Concorde is a fine example of that.
Once again thanks
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Intelligent Television and Video

Nick Thomas
August 30, 2010, 23:01:00 GMT
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Post: 5902756
M2dude I have another question concerning "debow" You very clearly answered my original question on another thread. I just wondered how the engine was kept at a sub idle 30% N2? Was it done by careful metering of the fuel? and if not how was it done? I ask because the throttles would be closed during start up.
The whole engine installation with the ramps, spill doors, reheats and noozles must have been a nightmare to "fine tune" through all the different phases of flight.
Thanks for the explanation of how the pitch was "trimmed" Due to Concorde having elevrons instead of ailerons; was the aileron trim dealt with in a similar way? I guess the rudder trim could be applied normally.
Thanks again
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): Afterburner/Re-heat  Rudder

Nick Thomas
August 31, 2010, 23:19:00 GMT
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Post: 5905175
Hi everyone
Please correct me if am wrong but was there not a slender delta wing prototype built by Fairley in the middle fifties. As I understand it, the plane was built to study a delta wing performance at low speeds. Therefore it had a fixed undercarriage.
Regards
Nick

Subjects: None

Nick Thomas
September 01, 2010, 07:16:00 GMT
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Post: 5905640
Thanks M2dude. You are right and my memory is getting worse due to old age!
Regards
Nick

Subjects: None

Nick Thomas
September 02, 2010, 23:42:00 GMT
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Post: 5909855
Hi canuck, I must admit to being rather jealous that you flew on Concorde! Your questions are particularly interesting as they arise from personal experience. Then to discover that M2dude was involved in overcoming the problem and explains it all so clearly is a delight.
Landing Concorde must have been "quite interesting". When ever I see videos of it; I always wonder how high up the eyeline of the pilots are compared to other airlines and especially when compared to the eyeline of a 747 pilot?(when the main wheels touch) I guess this must change the view of the runway when crossing the threshold. If so was special training required to overcome this as I would have thought that it would initially be tempting(though ill advised) to cross the threshold at too low an altitude? I know that the FE would call out the radio altimeter heights on landing but it must at first be difficult to disbelive the evidence of your own eyes.
I think am right to assume there were no spoilers so on landing did the act of bring the nose down spoil the lift or is that the reason why the non flying pilot pushed the yolk forward once she was down?
Thanks
Nick

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Nick Thomas
September 05, 2010, 17:51:00 GMT
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Post: 5915727
Hi
I have yet another question! Last year I watched a programme where James May went up in a U2. He explained that at FL700 the plane was flying in "coffin corner" and that the difference in IAS between the stall and the max speed was only 10 knots. I understand that it's due to the very low air pressure at such heights. As Concorde could fly up to FL600 I wondered what this safe airspeed window was during the cruise/climb phase of flight and if this window was framed by the air pressure and/or the CofG position?
Once again thanks to everyone for such great answers and also for the background information.
Regards
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): C of G  IAS (Indicated Air Speed)

Nick Thomas
September 06, 2010, 11:18:00 GMT
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Post: 5917019
Thanks CJ and M2Dude for such complete answers. When I was typing "air pressure" I knew it was not quite the right term; so M2dude thanks for explaining that the correct term is "air density".
Would I be right in thinking that TAS is different from speed over the ground? I presume GS would be TAS plus or minus wind speed.
Regards
Nick

Subjects (links are to this post in the relevant subject page so that this post can be seen in context): TAS (True Air Speed)