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Old 26th Apr 2011, 23:42
  #1341 (permalink)  
 
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Vulcan Schematic

ChristianJ

Is this what you wanted ?

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Old 27th Apr 2011, 14:47
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Thanks, johnjosh43.

Not a hundred percent legible (lack of resolution), but I'll try to decipher it.

I agree, no trace of any electrical signalling ("FBW").

CJ
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Old 1st May 2011, 05:48
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Question Fuel Burn

I have been reading these all night, and find all this information really helpful in learning more about this wonderful aircraft.. I do have a question, what was the fuel burn in Mach 2 cruise?? I did not find anything specific about that, and I was just curious..

Thanks
Mark M
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Old 1st May 2011, 18:23
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About 18 tons an hour I think. More like 80 tons an hour at take-off! The higher and faster she went, the more efficient she became!
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Old 2nd May 2011, 20:13
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Thumbs up

Thats gotta be 18 tons (2000 lb) or roughly 9000 lbs per hour, at cruise?? The 80 ton to top of climb would be 40000 lbs an hour??? Wow..

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Mark
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Old 3rd May 2011, 11:28
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I don't know the fuel flow figures but from the type certificate data the max fuel load was 210,000 lbs and the max take off weight was 410,000 lbs. More than half its weight at take off was fuel.

The figure of 18 tons per hour or about 40,000 lbs per hour in the cruise would be about right as the max duration of flight was about 4 hours.
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Old 3rd May 2011, 11:37
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For a mid-cruise weight of say 300,000 lb and a lift/drag ratio of 7.5 the thrust required would have been 40,000 lbf and the powerplant sfc was around 1 lb/hr/lbf, so 40,000 lb/hr is just about right.

CliveL
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Old 3rd May 2011, 19:29
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Out of interest with any successor to concorde, what lift/drag ratio is now technically possible, and likewise from more advanced powerplants that could be available now what lb/hr/lbf numbers could be achieved?

One other question if I may - how much of a compromise was concorde's wing with respect to the balance of supersonic vs sub-sonic efficiency? What I'm trying to ask is if the wing could be a variable geometry with no weight cost (impossible I know) how much more efficient could the supersonic wing have become - or was the compromise very much on the sub-sonic performance and not much to gain in terms of supersonic efficiency?

Once more - thanks for all the great answers to the really intriguing questions!! I'm fascinated by Concorde - and regret I never had the means to fly on her whilst she was still where she belongs!
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Old 4th May 2011, 14:58
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Out of interest with any successor to concorde, what lift/drag ratio is now technically possible, and likewise from more advanced powerplants that could be available now what lb/hr/lbf numbers could be achieved?

One other question if I may - how much of a compromise was concorde's wing with respect to the balance of supersonic vs sub-sonic efficiency? What I'm trying to ask is if the wing could be a variable geometry with no weight cost (impossible I know) how much more efficient could the supersonic wing have become - or was the compromise very much on the sub-sonic performance and not much to gain in terms of supersonic efficiency?
I'll try!

The last time I had anything to do with it people were talking about L/Ds around 10.5 in cruise (up from 7.5).

There are technical issues why one cannot use high bypass engines for supersonic cruise, so the thermodynamic cycle would be much the same as the Olympus. That being so the only real gain would come from higher TETs today so the benefits would be limited - two or three percent sfc perhaps?

[Yes I know the USAF are flying supersonic cruise aircraft, but look at how much bypass their engines actually have and the supersonic cruise Mach Numbers]

Obviously the MOST IMPORTANT condition was supersonic cruise, so this dominated the compromise. OTOH, the reserve fuel was largely driven by subsonic performance, so one couldn't give too much away. It might surprise people, but the 0.93M specific range is much the same as the 2.0M value.

As for variable geometry wings (1970s style), the best I can offer is that Boeing started with a variable geometry design (with which they won the design competition), but as the design process progressed the amount of wing that varied got less and less until the Boeing aircraft looked very much like the Lockheed design that lost the original competition.

What do you think?

CiveL
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Old 4th May 2011, 22:06
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Concorde Take-Off. MTOW, LHR, Calm, ISA day, Fuel SG 0.80
Fuel Flow at Take Off, Reheat ON:
  • [*]
  • [*]
  • [*]
  • [*]
  • [*]
  • [*]
  • [*]


Concorde Cruise/Climb. 140,000 kgs, ISA, Still Air, Optimum altitude for her weight, speed and number of operating engines:
Fuel Flow in Cruise/Climb, Reheat OFF:
  • [*]
  • [*]
  • [*]


Concorde fuel usage.
  • [*]
  • [*]
  • [*]
  • [*]
  • [*]

Concorde Range reduction.

When we factor in the decel, descent, approach and landing (all of which had obviously been originally flight planned at subsonic speed anyway) and the actual decrease in range, following a speed reduction, was roughly:
  • M2.00 to M0.95 (four engines) a range reduction of 20%

  • M2.00 to M0.95 (three engines) a range reduction of 30%

It was this last figure, the circa 30% loss of range following an engine shutdown and subsequent deceleration to subsonic cruise, that perhaps most occupied the minds of her operating crews.

Coupled with the change from a generally benign environment of low winds and low temperatures at FL550+, to the more hostile environment of high temperatures and much stronger (head)winds to be expected around FL290, this meant that on routes such as LHR-BGI, the greater challenge was often keeping the 3-engined diversion airfield (usually ANU) in range, rather than the destination airfield (BGI).

Fortunately the fuel planning and monitoring on this route was eased greatly with the publication of some pilot-friendly "How-Goes-It" types of graphs and charts by one particularly bright Flight Engineer.

LHR-BGI, always a challenge, always enjoyable!


Best Regards

Bellerophon
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Old 5th May 2011, 06:00
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4e...FL520...M2.00...1,147 kts...5,783 kg/eng/hr...23,132 kg/h
I stand corrected, but am surprised it was so high
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Old 6th May 2011, 22:29
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CliveL

You got me a little worried there, so I've just checked the figures I quoted in case I'd slipped up! They were extracted from the Cruise Control Manual (rather than from observation on an actual flight) for a lecture some years ago.

I'm relieved to say they appear to be correct. By way of contrast, to show the variation in fuel flow there could be, the following is perhaps typical of Concorde approaching her decel/descent point into BGI.


Concorde Cruise/Climb. 110,000 kgs, FL600, ISA -15°C:
Fuel Flow in Cruise/Climb, Reheat OFF:
  • 4e...FL600...M2.00...1,107 kts...4,308 kg/eng/hr...17,232 kg/hr

Best Regards

Bellerophon
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Old 7th May 2011, 06:14
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Bellerephon

Digging a little I see that your numbers correspond to an sfc of 1.23 where I was remembering a value around 1.0.
I forgot the installation losses

Best Regards

Clive
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Old 9th May 2011, 23:07
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So, uh, what's happening here?

Feòrag NicBhrìde - So, what's this then?

Some very odd activity around Concorde recently at LHR, or so the poster claims. No idea if the pic is genuine or how recent it is if so, but it can't be that old.
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Old 9th May 2011, 23:11
  #1355 (permalink)  
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Here's the link to the same image in Google Maps


So it is kosher.
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Old 10th May 2011, 08:32
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It’s a very out of date picture, even the structure hiding her has now been demolished, and there is a more up to date picture of her present location in the latest news section of Heritage Concorde
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Old 10th May 2011, 08:50
  #1357 (permalink)  
 
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June 27th, 2010 according to Google Earth
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Old 10th May 2011, 20:29
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Well Google is wrong!

She has been moved to the new location!!
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Old 10th May 2011, 20:49
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Google was right....

G-BOAB has been moved around LHR repeatedly, and she was indeed parked for some time inside the old "detuner" (engine run-up silencer), which is what that recent "what's this then" post and picture are all about.

It's a pity, really.... All the other British Concordes have found a "home" one way or another (except G-BOAF, maybe,, but let's not go into that for the moment), and G-BOAB is slowly becoming the "forgotten" Concorde.

CJ
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Old 11th May 2011, 05:13
  #1360 (permalink)  
 
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G-BOAB is slowly becoming the "forgotten" Concorde.
You could send her over here, I'm sure there plenty of people in Aus who would love to give lots of love and attention!
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