24th Aug 2010, 09:48
permalink Post: 88
Biggles78
The tailwheel design really was the one exception in poor design terms, but I'm sure that if the aircraft was doing what she should be doing right now, (you know routinely flying across the Atlantic and beyond, instead of languishing in museums), modifications would have finally put this particular malady to bed). In design terms, the rest of the aircraft was nothing short of a flying work of art, a masterpiece. Having said that though, personally I would rather that four rather than three hydraulic systems had been used. Originally there were four systems in the design, but the RED system was deleted, as it was felt to be superfluous. My own view is that this particular decision was total poppycock. Oh, and Green, Blue and Yellow hydraulic systems was something else that Airbus copied from Concorde.... although we ourselves pinched that idea off of the Comet
).
As far as the hydraulic expansion joints go, I will scour around and see if I can find a diagram for you. Try and picture two titanium (or stainless) tubes, on inside the other, with a sealed chamber being formed at the join. Inside this chamber were multiple lands fitted with special viton GLT seals. They did work incredibly well, although occasionally one of the seals gave out, and things got wet, VERY WET.
As far as the 4000 PSI hydraulic system, as EXWOK quite rightly pointed out, the loading on the flying control surfaces were immense throughout the whole flight envelope. (Picture alone just the T/O from JFK RWY 31L, where the aircraft is tightly turning and the gear retracting, all at the same time). As well as the flying controls and landing gear, you also had the droop nose to consider, four variable engine intakes as well as a couple of hydraulically operated fuel pumps. Oh, and in emergencies, a hydraulically driven 40 KVA generator too. The reason that 4000 PSI was chosen was that if a large amount of hydraulic 'work' was to be done, the only way to keep the size of jacks and actuators to a reasonable size/weight was to increase the system pressure by 25% from the normal 3000 PSI. (On the A380 they've gone a step further and gone for 5000 PSI, saving them over a tonne on the weight of the aircraft).
Concorde used a special hydraulic fluid, Chevron M2V. This is a mineral based fluid, as opposed to the ester based Skydrol, used by the subsonics. The reason that we went for a different fluid was a simple one; Skydrol is rubbish at the high temperatures that Concorde operated at, no good at all in fact, so we needed something better and in M2V we found the PERFECT fluid. As an aside, unlike Skydrol, that attacks paintwork, certain rubber seals, skin, EYES etc., M2V is completely harmless, wash your hair in it. (I did, several times when we had leaks. Thinking about it, maybe THAT is why my hair is such a diminished asset
EXWOK
It's so great having another of my pilot friends diving in to this post, welcome welcome
I remember the Mech' Signalling part of the air tests, my lunch has just finished coming back up thank you.
(for interest chaps and chapesses, with mechanical signalling, using just the conventional control runs under the floor, there was no auto-stabilisation).
The artificialfeel system worked incredibly well I thought, I always found it curious that the peak load law in the computer was at the transonic rather that the supersonic speed range. It was explained to me long ago that this was because the controls really are at their most sensitive here, but at high Mach numbers are partially 'stalled out', due to shockwave movements along the surfaces, and were therefore less effective. (For this reason I was told, the inner elevons were so critical for supersonic control, being the most effective of all elevons at high speed).
To all , I forgot to mention in my previous post regarding the engine failure in G-BOAF in 1980; I remember an FAA surveyor, who was taking a look at the carnage within the engine bay, saying that in his opinion, no other aircraft in the world could have survived the intensity of the titanium fire that ensued. Analysis showed that the fire was successfully extinguished, possibly at the first shot of the fire bottle. This was a testament to the way that the Concorde engine bay could be completely 'locked down' when the fire handle was pulled, as well as to the way that the whole engine installation was technically encased in armour plate. To put all this in context, acording to Rolls Royce a titanium fire, once it takes hold, can destroy the compressor of a jet engine in four seconds.
Dude
Quote:
|
M2
, it appears the tailwheel was, so far, the only "fault" in an otherwise extreme machine. Were there any other items like the tailwheel that were unworthy to be in her?
Does anyone have a tech drawing of the "sliding seals" used in the hydraulics. I have trouble visualising something that could withstand the 4,000psi pressure. Why was such a high pressure used? After all the control surfaces couldn't have required that much input to effect an authority movement. I understand it was also a special fluid that was used. Was this because of the pressure it was under or the temperature extremes? |
).
As far as the hydraulic expansion joints go, I will scour around and see if I can find a diagram for you. Try and picture two titanium (or stainless) tubes, on inside the other, with a sealed chamber being formed at the join. Inside this chamber were multiple lands fitted with special viton GLT seals. They did work incredibly well, although occasionally one of the seals gave out, and things got wet, VERY WET.
As far as the 4000 PSI hydraulic system, as EXWOK quite rightly pointed out, the loading on the flying control surfaces were immense throughout the whole flight envelope. (Picture alone just the T/O from JFK RWY 31L, where the aircraft is tightly turning and the gear retracting, all at the same time). As well as the flying controls and landing gear, you also had the droop nose to consider, four variable engine intakes as well as a couple of hydraulically operated fuel pumps. Oh, and in emergencies, a hydraulically driven 40 KVA generator too. The reason that 4000 PSI was chosen was that if a large amount of hydraulic 'work' was to be done, the only way to keep the size of jacks and actuators to a reasonable size/weight was to increase the system pressure by 25% from the normal 3000 PSI. (On the A380 they've gone a step further and gone for 5000 PSI, saving them over a tonne on the weight of the aircraft).
Concorde used a special hydraulic fluid, Chevron M2V. This is a mineral based fluid, as opposed to the ester based Skydrol, used by the subsonics. The reason that we went for a different fluid was a simple one; Skydrol is rubbish at the high temperatures that Concorde operated at, no good at all in fact, so we needed something better and in M2V we found the PERFECT fluid. As an aside, unlike Skydrol, that attacks paintwork, certain rubber seals, skin, EYES etc., M2V is completely harmless, wash your hair in it. (I did, several times when we had leaks. Thinking about it, maybe THAT is why my hair is such a diminished asset
EXWOK
It's so great having another of my pilot friends diving in to this post, welcome welcome
I remember the Mech' Signalling part of the air tests, my lunch has just finished coming back up thank you.
(for interest chaps and chapesses, with mechanical signalling, using just the conventional control runs under the floor, there was no auto-stabilisation).
The artificialfeel system worked incredibly well I thought, I always found it curious that the peak load law in the computer was at the transonic rather that the supersonic speed range. It was explained to me long ago that this was because the controls really are at their most sensitive here, but at high Mach numbers are partially 'stalled out', due to shockwave movements along the surfaces, and were therefore less effective. (For this reason I was told, the inner elevons were so critical for supersonic control, being the most effective of all elevons at high speed).
To all , I forgot to mention in my previous post regarding the engine failure in G-BOAF in 1980; I remember an FAA surveyor, who was taking a look at the carnage within the engine bay, saying that in his opinion, no other aircraft in the world could have survived the intensity of the titanium fire that ensued. Analysis showed that the fire was successfully extinguished, possibly at the first shot of the fire bottle. This was a testament to the way that the Concorde engine bay could be completely 'locked down' when the fire handle was pulled, as well as to the way that the whole engine installation was technically encased in armour plate. To put all this in context, acording to Rolls Royce a titanium fire, once it takes hold, can destroy the compressor of a jet engine in four seconds.
Dude
7th Sep 2010, 10:02
permalink Post: 254
for atakacs:
Quote:
| Makes me wonder... In the event of a complete loss of thrust at Mach 2 (say fuel contamination) would the deceleration be significant ? If so I guess the fuel redistribution / pumping to maintain acceptable CG would become interesting... |
The drag incurred flying supersonic was once described to me as like flying through wood, not air. The only times I ever closed all 4 throttles at M2 was dealing with surges (see earlier posts on the subject). While not quite like flying into teak, the decel was very impressive - it more than once resulted in a member of cabin crew appearing in the flt deck in a semi-seated position, grimly trying to stop a fully loaded galley cart.......
As for four-engine flameouts - perish the thought. The checklists, like many, depended on flight phase;
Above M1.2 it was expected that windmilling would provide adequate eletric and hydraulic power so the c/list aimed to start a fuel txfr forward, use the spare hydraulic system to drive half the PFCUs, ensure a fuel supply to the engs and ensure cooling to equipment.
Below M1.2 the RAT would be deployed, it was less likely that the standard means of fuel txfr would work so valves were overridden and the hydraulic fuel pumps brought into use, and the Mach fell further the PFCUs were put on half-body use only, using the stby hydraulic system.
You weren't far from the ground, in time, at this stage so it was a good time to get an engine relit!
Given the Olympus' auto-relight capability a four engine loss was going to be caused by something fairly drastic.
2nd Oct 2010, 08:45
permalink Post: 508
CRON
I can only speak here from the Concorde ground engineering school that I attended over a total of 13 weeks at Filton in 1980 and 1981; the pilot/flight engineer questions there were I'm sure FAR nastier (and also more operationally specific); we did get to share simulator time though, which was really useful. Like the aircrews, we stayed up in a hotel in Bristol during the week. (I personally had only left BAC, as it was then, for BA at Heathrow in late July 1977, so I was returning to familiar pastures). The exam format would be several dozen multi-choice questions per week/phase; a typical question would go something like:
The Inner Elevon Light, plus 'PFC' red Master Warning is triggered by:
a) The Green Flying ControlComparator
b) The Blue Flying Control Comparator
c) Either Comparator
The correct answer is (b).
Another flying controls question I can remember is:
Outer Elevon Neutralisation is triggered at:
a)Vmo + 10 KTS
b)Vmo + 15 KTS
c)Vmo + 25 KTS
The correct answer here is (c).
The pass mark in these exams was 75%, with penalty marking applied for any wrong answers. I always found the worst part was the fact that the exams were on a Friday afternoon after lunch
Nick Thomas
Hi again Nick, one really for the likes of BRIT312, EXWOK etc, but there was, as was mentioned before, an emergency forward transfer switch in the roof panel above the pilots (F/O's side if I remember correctly). When placed to the emergency poition two electric and two hydraulic fuel pumps for the rear trim tank #11 would start up automatically, as well as the forward tank inlet valves being opened also.
From what you said about the 'lady' being ahead of her time, I would certainly agree with you here; in my view she was generations ahead of everything else.
nomorecatering
The BA simulator that resided at Filton has been re-located to Brooklands Museum, and has been re-activated, but without motion and I'm not sure about full visuals either. I've not seen it myself yet, but I'm told that things have progressed really well with the operation. Obviously it is no longer certified as an active simulator; I'm not sure about the situation in France, perhaps my friend ChristiaanJ can answer that one.
I seem to remember typical loads for LHR-JFK being around 93-96 tonnes, depending on the passenger load and en-route conditions. Full tanks, depending on the SG was around 96 Tonnes. High fuel temperatures in the summer were a major pain; restricting maximum onload due to the low SG.
As far as ground school notes, mine are all out on long term loan (MUST get them back). The ground school are totally priceless and I am sure that there are many complete sets lying around in atticks/bedrooms/garages/loos etc.
Dude
Quote:
| If I may ask - and folk can recall - what would a sample question look like from these exams? |
The Inner Elevon Light, plus 'PFC' red Master Warning is triggered by:
a) The Green Flying ControlComparator
b) The Blue Flying Control Comparator
c) Either Comparator
The correct answer is (b).
Another flying controls question I can remember is:
Outer Elevon Neutralisation is triggered at:
a)Vmo + 10 KTS
b)Vmo + 15 KTS
c)Vmo + 25 KTS
The correct answer here is (c).
The pass mark in these exams was 75%, with penalty marking applied for any wrong answers. I always found the worst part was the fact that the exams were on a Friday afternoon after lunch
Nick Thomas
Quote:
| So I have been wondering if there were any special procedures for managing the CofG in a rapid descent especially as there could also be many other factors needing the crews attention? |
From what you said about the 'lady' being ahead of her time, I would certainly agree with you here; in my view she was generations ahead of everything else.
nomorecatering
Quote:
| Are there any concorde simulators that are still working and retain their certification? |
Quote:
| Regarding LHR JFK routes. What was the avarage fuel load and how close to full tanks was it. |
As far as ground school notes, mine are all out on long term loan (MUST get them back). The ground school are totally priceless and I am sure that there are many complete sets lying around in atticks/bedrooms/garages/loos etc.
Dude
Last edited by M2dude; 2nd Oct 2010 at 13:40 .
15th Oct 2010, 22:25
permalink Post: 574
Ze Concorde Quiz Mk 2 (Or is it Mach 2?).
As requested here is the second in the diabolical series of Concorde quizes. If you were never personally involved withe the aircraft you can leave out the really stinky questions if you want. Most answers can be found either in this thread, by looking at the many panel photos around or as usual by asking Mr Google
1) How many Concorde airframes were built?
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?).
1) How many Concorde airframes were built?
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?).
5) There were no less than FORTY SIX fuel pumps on Concorde. What was the breakdown for these? (Clue; don't forget the scavange pump
).
).
6) What was the only development airframe to have a TOTALLY unique shape?
7) This one is particularly aimed at ChristiaanJ. What was the total number of gyros on the aircraft?
8) How many wheel brakes?
9) What Mach number was automatic engine variable intake control enabled?
10) Above each bank of engine instruments were three lights, a blue, a green and an amber. What did they each signify?
11) At what airfied were the first BA crew base training details held?
12) What LHR runways did Concorde use for landing and take-off? (Trick question, not as obvious as it might seem).
13) What operator had serious plans to operate Concorde from SNN to JFK in the early 1980's?
14) What development aircraft did not exceed Mach 2 until fifteen months after her maiden flight?
Answers in 7 days, if further guidence (or clues) required then feel free to IM me.
Dude
Last edited by M2dude; 16th Oct 2010 at 08:00 . Reason: Addition of missing question... I am sooo nasty.
16th Oct 2010, 14:47
permalink Post: 577
questions
Humble SLF here, hope it is ok to have a stab at the questions, mods please feel free to delete if necessary.
1) How many Concorde airframes were built?
22, 20 that flew and 2 test frames
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
New York, Washington, Miami, Barbados, Toronto, Bahrain and Singapore, no British registered aircraft ever operated to or form Dallas, should not forget BAs most popular destination of all time-London
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
0930-Local
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?).
193 & 195 respectiveley
5) There were no less than FORTY SIX fuel pumps on Concorde. What was the breakdown for these? (Clue; don't forget the scavange pump ).
Pass
6) What was the only development airframe to have a TOTALLY unique shape?
101, G-AXDN
7) This one is particularly aimed at ChristiaanJ. What was the total number of gyros on the aircraft?
pass
8) How many wheel brakes?
8
9) What Mach number was automatic engine variable intake control enabled?
1.3
10) Above each bank of engine instruments were three lights, a blue, a green and an amber. What did they each signify?
Not sure here, best guess -green was part of the take-off moniter -red failure-blue reverse
11) At what airfied were the first BA crew base training details held?
Prestwick, shannon, and one in France
12) What LHR runways did Concorde use for landing and take-off? (Trick question, not as obvious as it might seem).
28L , 28R, 27L, 27R, 9L, 9R 10L 10R, 23
13) What operator had serious plans to operate Concorde from SNN to JFK in the early 1980's?
Fed-ex
14) What development aircraft did not exceed Mach 2 until fifteen months after her maiden flight?
214? G-BFKW
1) How many Concorde airframes were built?
22, 20 that flew and 2 test frames
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
New York, Washington, Miami, Barbados, Toronto, Bahrain and Singapore, no British registered aircraft ever operated to or form Dallas, should not forget BAs most popular destination of all time-London
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
0930-Local
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?).
193 & 195 respectiveley
5) There were no less than FORTY SIX fuel pumps on Concorde. What was the breakdown for these? (Clue; don't forget the scavange pump ).
Pass
6) What was the only development airframe to have a TOTALLY unique shape?
101, G-AXDN
7) This one is particularly aimed at ChristiaanJ. What was the total number of gyros on the aircraft?
pass
8) How many wheel brakes?
8
9) What Mach number was automatic engine variable intake control enabled?
1.3
10) Above each bank of engine instruments were three lights, a blue, a green and an amber. What did they each signify?
Not sure here, best guess -green was part of the take-off moniter -red failure-blue reverse
11) At what airfied were the first BA crew base training details held?
Prestwick, shannon, and one in France
12) What LHR runways did Concorde use for landing and take-off? (Trick question, not as obvious as it might seem).
28L , 28R, 27L, 27R, 9L, 9R 10L 10R, 23
13) What operator had serious plans to operate Concorde from SNN to JFK in the early 1980's?
Fed-ex
14) What development aircraft did not exceed Mach 2 until fifteen months after her maiden flight?
214? G-BFKW
16th Oct 2010, 21:12
permalink Post: 579
1) How many Concorde airframes were built?
22 total. 2 test, 9 BA, 9 AF, 2 spares (1 BA, 1 AF).
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
JFK, Dulles Intl., Barbados, Miami, Bahrain, Singapore.
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
No idea.
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?).
No idea.
13 tanks, 2 main pumps each (except tank 11 which had 4 pumps) = 28
Main and aux engine feed pumps (3 per collector, 4 collectors for a total of 12)
Fuel pumps from aux tanks to mains = 4
Fuel dump = 2
BAC 221. Flying test bed for the wing design.
Filton.
27 L/R, 09 R.
22 total. 2 test, 9 BA, 9 AF, 2 spares (1 BA, 1 AF).
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
JFK, Dulles Intl., Barbados, Miami, Bahrain, Singapore.
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
No idea.
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?).
No idea.
5) There were no less than FORTY SIX fuel pumps on Concorde. What was the breakdown for these? (Clue; don't forget the scavange pump
).
).
13 tanks, 2 main pumps each (except tank 11 which had 4 pumps) = 28
Main and aux engine feed pumps (3 per collector, 4 collectors for a total of 12)
Fuel pumps from aux tanks to mains = 4
Fuel dump = 2
6) What was the only development airframe to have a TOTALLY unique shape?
BAC 221. Flying test bed for the wing design.
7) This one is particularly aimed at ChristiaanJ. What was the total number of gyros on the aircraft?
I'm guessing 14.
I'm guessing 14.
8) How many wheel brakes?
8. 1 per wheel, 4 total on each main gear.
8. 1 per wheel, 4 total on each main gear.
9) What Mach number was automatic engine variable intake control enabled?
Mach 1.3.
Mach 1.3.
10) Above each bank of engine instruments were three lights, a blue, a green and an amber. What did they each signify?
Blue = Reverse
Amber = Reheat failure
Green = Good to go
Blue = Reverse
Amber = Reheat failure
Green = Good to go
11) At what airfied were the first BA crew base training details held?
Filton.
12) What LHR runways did Concorde use for landing and take-off? (Trick question, not as obvious as it might seem).
27 L/R, 09 R.
13) What operator had serious plans to operate Concorde from SNN to JFK in the early 1980's?
Braniff.
Braniff.
14) What development aircraft did not exceed Mach 2 until fifteen months after her maiden flight?
Concorde? Just a guess.
ECAM Actions.
Concorde? Just a guess.
ECAM Actions.
Last edited by ECAM_Actions; 16th Oct 2010 at 21:38 .
16th Oct 2010, 22:27
permalink Post: 580
OK, I see others have already posted answers.
I've carefully avoided looking at them, but I'll might as well plug in mine now.
My personal problem is that I was involved in the very earliest days, before the aircraft went into service, and then in the last days and afterwards...
So the questions dealing with the in-service period are totally outside my field of experience... all I can do is guess, in case I saw the answers somewhere.
1) How many Concorde airframes were built?
Twenty-two.
Two static-test airframes.
- One at Toulouse, for purely static tests, and tests such as vibration and flutter.
- One at Farnborough, for the long-duration thermal fatigue tests.
(A few bits and pieces of the Farnborough test specimen have survived, and can still be seen at the Brooklands museum).
Two prototypes (001 and 002)
Two pre-production aircraft (01 and 02)
Two production aircraft used for certification, that never entered service (201 - F-WTSB and 202 - G-BBDG)
Fourteen production aircraft, seven that served with British Airways, seven that served with Air France.
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
Not a clue as to the full list.
- Bahrain, obviously.
- JFK.
- IAD (not sure if that's rated as regular, or only incidental)
- Dallas (with Braniff)
- Barbados (of course, right until the end)
- Sngapore (with Singapore Airlines, and G-BOAD in Singapore Airlines colours on one side)
- Sydney (again no idea if that rated as a regular flight or only a few tries)
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
Not a clue either. Vague memory of about 10:00 am which gave you a full working day in New York.
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?)..
Never flew on them, never had to deal with them.
BA174 comes to mind from the depths of my memory, in that case BA003 would have been BA176?
5) There were no less than FORTY SIX fuel pumps on Concorde. What was the breakdown for these? (Clue; don't forget the scavenge pump )
M2dude, I did AFCS, not the fuel system. I believe you, but without pulling out some diagrams I honestly have NO idea.
I expect each tank had at least two pumps, which gets me up to 26.
Then there were a few emergency pumps for the trim tanks, and I suppose each engine had additional pumps associated with it.
Still nowhere near the 46 I need to find.....
6) What airframe had the only TOTALLY unique shape?
That would have been my old friend, 01 (G-AXDN), first pre-production aircraft, now at Duxford.
It was the first Concorde with the new transparent visor, but it still had the short tail that characterised the prototypes.
It was 02 (F-WTSA), the first French pre-production aircraft, that was close to the final shape of the production aircraft.
7) This one is particularly aimed at ChristiaanJ. What was the total number of gyros on the aircraft?
Good question.... never counted them all. But I'll try a guess.
First a nice one, the SFENA Emergency Standby Artificial Horizon (made by the firm I worked for).
Ran off the Emergency Battery Bus via a small independent inverter.
And if that failed too, it would still run reliably for several minutes on its own inertia.
Next, the rate gyros used by the autostabilisation system ; these measured the angular rate of the aircraft along the three main axes, pitch, roll and yaw.
There were six, three each for the two autostab systems.
Now the rest....
Each IMU (inertial measurement unit, part of the inertial naviagation system) had three gyros.
With three INS on board, that would make nine.
Much as I try, I can't remember other ones, so I'll look forward to the final answer.
I can imagine the weather radar using an additional gyro for stabilisation, but I never went there.
8) How many wheel brakes?
Unless this is a trick question, I would say eight, for each of the main gear wheels.
The nose gear did not have any brakes - unless there were some small ones to stop the wheels rotating after retraction of the gear, but not used during landing.
9) What Mach number was automatic engine variable intake control enabled?
No idea.
Mach 1.0 or thereabouts is my personal guess only.
10) Above each bank of engine instruments were three lights, a blue, a green and an amber. What did they each signify?
I know that they each monitored the status of one of the engines, because it was too complex for the pilots to fully monitor all the parameters of all four engines in the short time between start-of-roll and V1... they had too many other things to do.
But I don't remember what each light meant, would have to look it up in the manual.
11) At what airfied were the first BA crew base training details held?
No idea.
Was it Brize Norton, or Casablanca?
12) What LHR runways did Concorde use for landing and take-off? (Trick question, not as obvious as it might seem).
No idea.
Vague memory of it being systematically the North runway for noise issues.
13) What operator had serious plans to operate Concorde from SNN to JFK in the early 1980's?
No idea.
14) What development aircraft did not exceed Mach 2 until fifteen months after her maiden flight?
I would expect the obvious answer to be 002.
Working up from first flight to Mach 2 was a slow and laborious process, and in the end it was 001 that both flew first, and also went to Mach 2 first.
I don't think any of the other aircraft took that long.
A I said, I tried to answer all questions "off the top of my head", without looking at any other sources.
CJ
I've carefully avoided looking at them, but I'll might as well plug in mine now.
Quote:
|
Originally Posted by
M2dude
If you were never personally involved withe the aircraft you can leave out the really stinky questions if you want.
|
So the questions dealing with the in-service period are totally outside my field of experience... all I can do is guess, in case I saw the answers somewhere.
1) How many Concorde airframes were built?
Twenty-two.
Two static-test airframes.
- One at Toulouse, for purely static tests, and tests such as vibration and flutter.
- One at Farnborough, for the long-duration thermal fatigue tests.
(A few bits and pieces of the Farnborough test specimen have survived, and can still be seen at the Brooklands museum).
Two prototypes (001 and 002)
Two pre-production aircraft (01 and 02)
Two production aircraft used for certification, that never entered service (201 - F-WTSB and 202 - G-BBDG)
Fourteen production aircraft, seven that served with British Airways, seven that served with Air France.
2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc.
Not a clue as to the full list.
- Bahrain, obviously.
- JFK.
- IAD (not sure if that's rated as regular, or only incidental)
- Dallas (with Braniff)
- Barbados (of course, right until the end)
- Sngapore (with Singapore Airlines, and G-BOAD in Singapore Airlines colours on one side)
- Sydney (again no idea if that rated as a regular flight or only a few tries)
3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either).
Not a clue either. Vague memory of about 10:00 am which gave you a full working day in New York.
4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?)..
Never flew on them, never had to deal with them.
BA174 comes to mind from the depths of my memory, in that case BA003 would have been BA176?
5) There were no less than FORTY SIX fuel pumps on Concorde. What was the breakdown for these? (Clue; don't forget the scavenge pump )
M2dude, I did AFCS, not the fuel system. I believe you, but without pulling out some diagrams I honestly have NO idea.
I expect each tank had at least two pumps, which gets me up to 26.
Then there were a few emergency pumps for the trim tanks, and I suppose each engine had additional pumps associated with it.
Still nowhere near the 46 I need to find.....
6) What airframe had the only TOTALLY unique shape?
That would have been my old friend, 01 (G-AXDN), first pre-production aircraft, now at Duxford.
It was the first Concorde with the new transparent visor, but it still had the short tail that characterised the prototypes.
It was 02 (F-WTSA), the first French pre-production aircraft, that was close to the final shape of the production aircraft.
7) This one is particularly aimed at ChristiaanJ. What was the total number of gyros on the aircraft?
Good question.... never counted them all. But I'll try a guess.
First a nice one, the SFENA Emergency Standby Artificial Horizon (made by the firm I worked for).
Ran off the Emergency Battery Bus via a small independent inverter.
And if that failed too, it would still run reliably for several minutes on its own inertia.
Next, the rate gyros used by the autostabilisation system ; these measured the angular rate of the aircraft along the three main axes, pitch, roll and yaw.
There were six, three each for the two autostab systems.
Now the rest....
Each IMU (inertial measurement unit, part of the inertial naviagation system) had three gyros.
With three INS on board, that would make nine.
Much as I try, I can't remember other ones, so I'll look forward to the final answer.
I can imagine the weather radar using an additional gyro for stabilisation, but I never went there.
8) How many wheel brakes?
Unless this is a trick question, I would say eight, for each of the main gear wheels.
The nose gear did not have any brakes - unless there were some small ones to stop the wheels rotating after retraction of the gear, but not used during landing.
9) What Mach number was automatic engine variable intake control enabled?
No idea.
Mach 1.0 or thereabouts is my personal guess only.
10) Above each bank of engine instruments were three lights, a blue, a green and an amber. What did they each signify?
I know that they each monitored the status of one of the engines, because it was too complex for the pilots to fully monitor all the parameters of all four engines in the short time between start-of-roll and V1... they had too many other things to do.
But I don't remember what each light meant, would have to look it up in the manual.
11) At what airfied were the first BA crew base training details held?
No idea.
Was it Brize Norton, or Casablanca?
12) What LHR runways did Concorde use for landing and take-off? (Trick question, not as obvious as it might seem).
No idea.
Vague memory of it being systematically the North runway for noise issues.
13) What operator had serious plans to operate Concorde from SNN to JFK in the early 1980's?
No idea.
14) What development aircraft did not exceed Mach 2 until fifteen months after her maiden flight?
I would expect the obvious answer to be 002.
Working up from first flight to Mach 2 was a slow and laborious process, and in the end it was 001 that both flew first, and also went to Mach 2 first.
I don't think any of the other aircraft took that long.
A I said, I tried to answer all questions "off the top of my head", without looking at any other sources.
CJ
22nd Oct 2010, 09:26
permalink Post: 597
Ze Concorde Quiz Mk 2 (Or is it Mach 2?).... Ze Answers
OK guys, here are the answers. If you disagree about any of them then fire away, the old memory certainly 'aint perfect.
As many of you have guessed, there were 22: The 14 production airframes, the 2 production series development aircraft (201 & 202), the 2 pre-production airframes (101 & 102) and the 2 prototypes 001 & 002. PLUS, the major fatigue test specimen at the RAE Farnborough and the static test specimen at CEAT in Toulouse. The CEAT tests actually tested the wing to destruction; I seem to remember it was something like a 200% overload before the wing failed at the root. And great but rather sad pictures
VOLUME
, never seen these before.
OK, from MY memory
, we have: London LHR (duhhh!!), Bahrein BAH, Singapore SIN, New York JFK, Washington IAD, Dallas DFW, Miami MIA, Toronto YYZ, Barbados BGI, and Riyadh RUH. As well as charters being ommited, so are some of the special 'surprise' shuttle appearances that Concorde would make, substituting a subsonic to and from destinations such as Manchester and Edinburgh.
11:15
The BA193 and BA 195.
OK, there were 12 engine feed pumps (3 per engine) 8 main transfer tank pumps (2 each for the transfer tanks 5, 6, 7 & 8), 4 'A' tank pumps (2 each for 5A & 7A), 8 trim-transfer tank pumps (2 electric pumps each for tanks 9, 10 & 11 PLUS 2 hydraulically driven pumps for tank 9), 4 electric engine start pumps (there was a single electric start pump per engine that delivered fuel to it's own dedicated start atomiser in the combustion chamber. The pump automatically ran when the engine HP valve was set to OPEN and would continue running for 30 seconds after the DEBOW switch was returned to the 'normal' position), 4 engine first stage pumps (a single mechanically driven pump per engine), 4 second stage pumps (a single pneumatically driven pump, sometimes termed 'the turbopump, per engine. This would cut out at around 20,000'), our scavenge tank pump (triggered automatically when there was 7 US gallons in the tank; pumping it back into tank 2. This pump was identical to an 'A' tank transfer pump), and FINALLY, a single de-air pump for tank 10. The pump would drive the fuel through a mesh, removing air bubbles from the fuel. Tank 11 used the L/H trim pump for de-air (similar principle)and would be switched on during take-off. This is why the tank 5 trim inlet valve being set to over-ride OPEN would result in the tank being highly pressurised in the case of the Gonesse disaster; the pump would obviously pressurise the L/H trim gallery and any tank on that side with an open inlet valve!!!
G-AXDN, aircraft 101. (A production wing, fuselage, droop nose and intakes, but with the short tail section and secondary nozzles of the prototypes.
Ready ChristiaanJ? There were 18....Yes, the single SFENA standby horizon, 9 INS gyros (one per X,Y and Z platform in each of the 3 INUs), 8 autostab' rate gyros (one per axis for each of the 2 autostab' computers PLUS a monitor gyro for the pitch axis). The radar by the way used attitude signals from the INS.
9. One per main wheel plus the single 'in flight braking' nose wheel brake.
Mach 0.7!!! Between this and Mach 1.26 the intake surfaces were positioned as a function of engine N1 if the engine was shut down for any reason. (Otherwise of course the intake surfaces were fully up). You needed a sub idle N1 of 57% and below for all this to happen, and it was to assist relight performance and reduce buffet. Between Mach 1.26 and 1.32 the ramps were driven down slightly to about 5%, full supersonic scheduling itself commencing at Mach 1.32.
Already brilliantly answered by Brit312 (as well as the FSLabs diagram). Yep, Geen GO, T/O monitor armed, fuel flow and P7 at or above datum, A/C on ground, reverse not selected and CON light not on. Amber CON (Reheat selected and not detected, N1 OK or reverse selected and primary nozzle (Aj) not at minimum. Blue REV; steady buckets at reverse, flashing buckets in transit.
Fairford, followed by Brize Norton, and then a host of airfields from Prestwick and Shannon to Chateauroux.
OK, probably no surprises now:
Landing - 27L & R, 9L & R (prior to LHR mag' deviation update were 28L & R & 10L & R) together with 23/05.
Take off - 27L (28L), 9R (10R) and 9L. (10L never happened as take offs on this runway only occurred in 2003).
It was FedEx, they planned to operate two stripped out aircraft, leased from BA, between Shannon and JFK as high value parcel carriers. The idea was that parcels would be flown in from all over Europe by small FedEx feeder aircraft and the parcels transferred to Concorde which would then speed on to JFK in around 2 1/2 hours. It never happened because of a combination of economics appraisal by FedEx and BA deciding that it could would not release the aircraft anyway.
A/C 101, G-AXDN first flew on 17th December 1971 with FIXED INTAKES!! (101 was going to be the launch vehicle for the new digital intake control system, but the 'boxes' were still being designed). This placed an operating limit of Mach 1.5 on the aircraft, limiting her ability with such a restricted flight envelope. She returned to Filton in late 1972 for installation of the system, as well as the new Olympus 593-602 engine. (The engine, very similar to the production Mk 610 version, used a quite revolutionary annular combustion chamber, and eliminated at a stroke the thick smoke exhaust that had up to then been Concorde's unwanted visual signiture). The aircraft flew more or less smokeless on 15 March 1973, achieving Mach 2 soon afterwards. As ChristiaanJ pointed out, the British prototype 002 had a similar gap, actually significantly higher, of 19 months. (The French aircraft 001 had an even longer gap of some 20 months).
I hope you guys had fun with this one, regards to all
Dude
Quote:
| 1) How many Concorde airframes were built? |
Quote:
| 2) As far as the British constructed aircraft went, name the destinations that were served?. Regular flight numbers only, excludes charters etc. |
, we have: London LHR (duhhh!!), Bahrein BAH, Singapore SIN, New York JFK, Washington IAD, Dallas DFW, Miami MIA, Toronto YYZ, Barbados BGI, and Riyadh RUH. As well as charters being ommited, so are some of the special 'surprise' shuttle appearances that Concorde would make, substituting a subsonic to and from destinations such as Manchester and Edinburgh.
Quote:
| 3) What was the departure time for the ORIGINAL morning LHR-JFK Concorde services? (Not called the BA001 then either). |
Quote:
| 4) Further to question 3 above, what WERE the original flight numbers for the BA001 and BA003? (The morning and evening LHR-JFK services?). |
Quote:
|
5) There were no less than FORTY SIX fuel pumps on Concorde. What was the breakdown for these? (Clue; don't forget the scavenge pump
).
|
Quote:
| 6) What was the only development airframe to have a TOTALLY unique shape? |
Quote:
| 7) This one is particularly aimed at ChristiaanJ. What was the total number of gyros on the aircraft? |
Quote:
| 8) How many wheel brakes? |
Quote:
| 9) What Mach number was automatic engine variable intake control enabled? |
Quote:
| 10) Above each bank of engine instruments were three lights, a blue, a green and an amber. What did they each signify? |
Quote:
| 11) At what airfield were the first BA crew base training details held? |
Quote:
| 12) What LHR runways did Concorde use for landing and take-off? (Trick question, not as obvious as it might seem). |
Landing - 27L & R, 9L & R (prior to LHR mag' deviation update were 28L & R & 10L & R) together with 23/05.
Take off - 27L (28L), 9R (10R) and 9L. (10L never happened as take offs on this runway only occurred in 2003).
Quote:
| 13) What operator had serious plans to operate Concorde from SNN to JFK in the early 1980's? |
Quote:
| 14) What development aircraft did not exceed Mach 2 until fifteen months after her maiden flight? |
I hope you guys had fun with this one, regards to all
Dude
Last edited by M2dude; 22nd Oct 2010 at 11:21 . Reason: oops, misssed out question 2
29th Oct 2010, 16:25
permalink Post: 627
jodelistie
First of all Rod, welcome to our Concorde thread, and thank you very much for your kind words.
Now as far as the rumour goes, I'm afraid that it is nonsense, however the truth is an even more complex story of collusion, betrayal and intrigue. You may read that 'Concorde was retired by BA and Air France purely due to economic reasons', however that is not quite the case (and as far as THIS side of the English Puddle goes, is total poppycock!!). Now BA lost a huge amount of her regular traffic as a result of the 9/11 tragedy and also as a result of the 2003 Iraq war, but things were improving nicely. In her 27 years of operation, Concorde had survived countless dips in her traffic, only to return stronger as market conditions improved.
It is early 2003, and French Concorde traffic to the USA has almost vanished, down to single digit loads. This is due mainly to total French opposition the impending US/UK invasion of Iraq, and US businessmen using BA Concorde almost exclusively. (French business seems to be boycotting the US altogether, so their contribution to passenger loads virtually ceased). Due to the apalling loads, AF are losing absolutely MILLIONS of Euros, at a time when the carrier is trying to privatise itself ... but there is more:
In the same February, AF very nearly lost ANOTHER Concorde, yet again largely down to total incompetence and lack of adherence to established procedures. Aircraft F-BTSD was flying between CDG and JFK when there was a failure of the reheat delivery pipe that runs from the engine 1st stage fuel pump to the reheat shut-off valve. This failure, although not particularly serious, led to a chain of events that very nearly resulted in the loss of the aircraft, and all those onboard. (Air France engines were overhauled seperately to BA, who never experienced this particular failure). What was required in the case of this failure was a precautionary engine shut-down, closing off the fuel supply to the engine totally, and a descent/deceleration to subsonic speed, carefully monitoring fuel consumption all the time. Unfortunately the crew 'forgot' to shut down the fuel LP valve, and this resulted in the fuel continuing to gush out of the failed pipe at an alarming rate. (Oh, and also they forgot to monitor the fuel consumption). Only after the crew FINALLY noticed that they were still losing fuel did they remember to close the engine LP valve, but it was almost too late. The aircraft just managed to land in Halifax, with barely enough fuel left in the tanks to taxi!! So, herer we are, AF are horrified that they have come very close to yet another disaster, knowing full well that yet again human error was a major factor.
But there is more....
One week later another AF aircraft loses part of a rudder panel due to de-lamination of the honeycomb surface, not particularly serious in itself, but it put even more jitters up the trousers of AF. (Rudder failures had happened to BA aircraft many years previous to this, but BA had purchased brand new and improved rudders from Airbus UK in Filton, but Air France chose not too).
So it seems that the chairmen of both Air France and Airbus (who regards Concorde as a waste of its valuable resources) have a 'secret' meeting to plan what was effectively the murder of Concorde. There is no way that AF want BA to carry on flying Concorde while they have to cease operations, so the plan is for Airbus to make a huge hike in their product support costs; these costs would have to be borne by BA exclusively, which they both knew would not be possible. If these support costs were not met, there would be no manufacturers support, and without this there would be no type certificate, and without this, no more Concorde.
Their (AF & Airbus) hope was that BA would not challenge this move legally, and sadly for the world of aviation they did not. At a meeting, BA AND AIR FRANCE!!!! were told by Airbus about the hike in product support costs, and BA would also have to cease operations. BA were not even allowed to continue until March 2004 (the Barbados season was nearly fully booked already), and so would have to cease operations in October 2003.
But the British were far from blameless in all this; a now retired very senior British airline person had always obsessively HATED Concorde, so the French conspiracy was a very early Christmas present for him; he finally got what he had always wanted. The 'end of Concorde' anouncement by both airlines was made in April 2003; AF had got what their executives wanted and finished flying in May, reluctantly leaving BA to fly until late October. If you want a full (and extremely well informed) explanation of what happened in that whole debacle, the article by Don Pevsner is worth reading. It can be found at this website:
THE BETRAYAL OF CONCORDE
There is absolutely no doubt in my mind that without the truly disgusting events in France in early 2003, Concorde would still be proudly flying for BA. (And with modifications and enhancements would fly safely for many more years).
quote** "in the hands of true professionals, Concorde was the safest aircraft that ever flew. and in the hands of BA crews at least, she was always just that..*
Oh and yes you were correct, the Olympus (the world's first ever 2 spool engine) was originally a 'Bristol-Siddeley' design, before BS were absorbed into Rolls-Royce. Stanley Hookers book is in my view totally superb, a true classic.
Dude
Quote:
| On which there was a splendid rumour that what put the final nail in the great birds coffin was that our transatlantic allies realised that if hijacked there was nothing that could catch her !! |
Now as far as the rumour goes, I'm afraid that it is nonsense, however the truth is an even more complex story of collusion, betrayal and intrigue. You may read that 'Concorde was retired by BA and Air France purely due to economic reasons', however that is not quite the case (and as far as THIS side of the English Puddle goes, is total poppycock!!). Now BA lost a huge amount of her regular traffic as a result of the 9/11 tragedy and also as a result of the 2003 Iraq war, but things were improving nicely. In her 27 years of operation, Concorde had survived countless dips in her traffic, only to return stronger as market conditions improved.
It is early 2003, and French Concorde traffic to the USA has almost vanished, down to single digit loads. This is due mainly to total French opposition the impending US/UK invasion of Iraq, and US businessmen using BA Concorde almost exclusively. (French business seems to be boycotting the US altogether, so their contribution to passenger loads virtually ceased). Due to the apalling loads, AF are losing absolutely MILLIONS of Euros, at a time when the carrier is trying to privatise itself ... but there is more:
In the same February, AF very nearly lost ANOTHER Concorde, yet again largely down to total incompetence and lack of adherence to established procedures. Aircraft F-BTSD was flying between CDG and JFK when there was a failure of the reheat delivery pipe that runs from the engine 1st stage fuel pump to the reheat shut-off valve. This failure, although not particularly serious, led to a chain of events that very nearly resulted in the loss of the aircraft, and all those onboard. (Air France engines were overhauled seperately to BA, who never experienced this particular failure). What was required in the case of this failure was a precautionary engine shut-down, closing off the fuel supply to the engine totally, and a descent/deceleration to subsonic speed, carefully monitoring fuel consumption all the time. Unfortunately the crew 'forgot' to shut down the fuel LP valve, and this resulted in the fuel continuing to gush out of the failed pipe at an alarming rate. (Oh, and also they forgot to monitor the fuel consumption). Only after the crew FINALLY noticed that they were still losing fuel did they remember to close the engine LP valve, but it was almost too late. The aircraft just managed to land in Halifax, with barely enough fuel left in the tanks to taxi!! So, herer we are, AF are horrified that they have come very close to yet another disaster, knowing full well that yet again human error was a major factor.
But there is more....
One week later another AF aircraft loses part of a rudder panel due to de-lamination of the honeycomb surface, not particularly serious in itself, but it put even more jitters up the trousers of AF. (Rudder failures had happened to BA aircraft many years previous to this, but BA had purchased brand new and improved rudders from Airbus UK in Filton, but Air France chose not too).
So it seems that the chairmen of both Air France and Airbus (who regards Concorde as a waste of its valuable resources) have a 'secret' meeting to plan what was effectively the murder of Concorde. There is no way that AF want BA to carry on flying Concorde while they have to cease operations, so the plan is for Airbus to make a huge hike in their product support costs; these costs would have to be borne by BA exclusively, which they both knew would not be possible. If these support costs were not met, there would be no manufacturers support, and without this there would be no type certificate, and without this, no more Concorde.
Their (AF & Airbus) hope was that BA would not challenge this move legally, and sadly for the world of aviation they did not. At a meeting, BA AND AIR FRANCE!!!! were told by Airbus about the hike in product support costs, and BA would also have to cease operations. BA were not even allowed to continue until March 2004 (the Barbados season was nearly fully booked already), and so would have to cease operations in October 2003.
But the British were far from blameless in all this; a now retired very senior British airline person had always obsessively HATED Concorde, so the French conspiracy was a very early Christmas present for him; he finally got what he had always wanted. The 'end of Concorde' anouncement by both airlines was made in April 2003; AF had got what their executives wanted and finished flying in May, reluctantly leaving BA to fly until late October. If you want a full (and extremely well informed) explanation of what happened in that whole debacle, the article by Don Pevsner is worth reading. It can be found at this website:
THE BETRAYAL OF CONCORDE
There is absolutely no doubt in my mind that without the truly disgusting events in France in early 2003, Concorde would still be proudly flying for BA. (And with modifications and enhancements would fly safely for many more years).
quote** "in the hands of true professionals, Concorde was the safest aircraft that ever flew. and in the hands of BA crews at least, she was always just that..*
Oh and yes you were correct, the Olympus (the world's first ever 2 spool engine) was originally a 'Bristol-Siddeley' design, before BS were absorbed into Rolls-Royce. Stanley Hookers book is in my view totally superb, a true classic.
Dude
Last edited by M2dude; 29th Oct 2010 at 16:52 . Reason: spelling (yet again) :-(
20th Nov 2010, 02:16
permalink Post: 744
M2 Dude
Back in August of 1997 I had the privilege of a ride in G-BOAC out of CYYZ on a flight to now where ie east of JFK up to FL550 Mach 2.0 etc.
It was back in a gentler day with a visit to the flight deck and I can still remember it all is if it was yesterday. As you can tell by web name I am industry and I really appreciated the short time I had in the Flight Deck. Unfortuneatly I was one of 99 that day so I did not get a chance to ask all the questions but the fuel system and fuel pump mini lecture from the flight engineer was stunning.
Please accept my sincere thank you and to Christian as well.
Like the Avro Arrow the TSR-2 the Concorde will live long in our minds.
One last comment many years ago we were number 2 on 09R in LHR and Concorde takes off in front of us. We were in an L-1011 that day and it shook as if a metal saw was trying to cut us in two. The Flight Service Director came running in white as a ghost and his first words were "What the #@&*" was that.........................
Please keep writing your story and if I ever run across you on the other side of the "pond" the bitter is on me
Back in August of 1997 I had the privilege of a ride in G-BOAC out of CYYZ on a flight to now where ie east of JFK up to FL550 Mach 2.0 etc.
It was back in a gentler day with a visit to the flight deck and I can still remember it all is if it was yesterday. As you can tell by web name I am industry and I really appreciated the short time I had in the Flight Deck. Unfortuneatly I was one of 99 that day so I did not get a chance to ask all the questions but the fuel system and fuel pump mini lecture from the flight engineer was stunning.
Please accept my sincere thank you and to Christian as well.
Like the Avro Arrow the TSR-2 the Concorde will live long in our minds.
One last comment many years ago we were number 2 on 09R in LHR and Concorde takes off in front of us. We were in an L-1011 that day and it shook as if a metal saw was trying to cut us in two. The Flight Service Director came running in white as a ghost and his first words were "What the #@&*" was that.........................
Please keep writing your story and if I ever run across you on the other side of the "pond" the bitter is on me
19th Dec 2010, 19:13
permalink Post: 893
Way back in August Tim 00 was asking about preset limits on the fuel transfer system.
One of the major challenges was to match the fuel transfer rate and initiation point to the aircraft performance. Once started the fuel pumps change the rate of CG shift in a more or less constant manner, but the aircraft acceleration through the transonic range is very dependent on weight and OAT, so the actual CG at any one mach number will vary from flight to flight. But it must be possible to make an emergency deceleration form any point in the acceleration backdown to subsonic conditions where the aerodynamic centre will be further forward and hence there is a risk that the aircraft might get into unstable conditions.
A lot of work went into this problem and the allowable CG boundaries reflect thsi to some extent.
CliveL
One of the major challenges was to match the fuel transfer rate and initiation point to the aircraft performance. Once started the fuel pumps change the rate of CG shift in a more or less constant manner, but the aircraft acceleration through the transonic range is very dependent on weight and OAT, so the actual CG at any one mach number will vary from flight to flight. But it must be possible to make an emergency deceleration form any point in the acceleration backdown to subsonic conditions where the aerodynamic centre will be further forward and hence there is a risk that the aircraft might get into unstable conditions.
A lot of work went into this problem and the allowable CG boundaries reflect thsi to some extent.
CliveL
17th Jan 2011, 18:40
permalink Post: 1117
Quote:
| For that reason, I believe, flight in mechanical signalling was removed from transonic flight on airtests and altogether from Base Training. The simulator was the only sensible way of trying to fly like that... |
Quote:
| Was there LH & RH Ignition selector switch maybe? |
Yes there was an Ignitor selector labelled LH--Both--RH, however the engines would be started using only one ignitor. This caused a few small but annoying delays as if the selected ignitor failed the start would have to be stopped the starter given a cooling period and then a further engine start using the other ignitor would be attempted, however it did give a running check that both ignitors were working.
This was not very popular with the crews and the ground engineers were persuaded to test the ignitors before presenting the aircraft for service. However due to the engine starting Fuel Pump switching, this resulted with a small fire in the hanger, and so the crews were back to starting on Lh or RH ignitors.
If I remember correctly the RR Conways on the VC-10 also had 2 ignitors per engine with a LH--Both-RH selector.
Quote:
| flying control pre-flight check! Learning it was a conversion course rite othat f |
If you remember, if something went wrong with the Flying control check the F/E was always busy. This gave him a chance to think up a suitable answer or even better the pilots did the check again and it now worked.
Quote:
| But the 'trainers' often used to come seek me out in the hangar and (over coffee, not beer I'm afraid) confer about various system quirks and nasties to use on you guys during the tech' refreshers |
Now I have to admit coming across the hanger to consult with you boys when preparing for a new sequence of F/E "Tech Knowledge Checks". Not that we did not understand it, you understand, but mainly to make sure that we were correct before some clever line F/E informed you of your error. Very embarrising that, and I should know
18th Jan 2011, 07:15
permalink Post: 1120
Brit312
The main problem with testing ignitors in the hangar was residual fuel. The LH ignitor sat right at the bottom of the can, and sometimes had a small puddle of fuel lying over it. This would produce a small 'whoof' of smoke out of the jet-pipe for about a second or two as the ignitors fired, but no more than that. The main danger was forgetting to trip the START PUMP C/Bs before you did the ignition check. If you did you had a guaranteed fire in the can (the pump would run as you know as soon as 'START' was selected and stayed running for 30 seconds after the start switch was returned to NORMAL) which was very messy (and scary as hell too). The only remedy was to grap a start truck, make sure the C/B is finally tripped and dry motor the engine until all the smokey stuff is gone. (It did no damage, but made a hell of a lot of smoke; the fire brigade were never best pleased). But provided the ignition checks were done correctly there was no ptoblem. (In nearly 30 years of doing ignition checks CORRECTLY, I never once saw a problem. Saw a few when people did forget to trip the start pump C/B however.
In any case as far as the 'ground engineers' doing the check of the ignitors, in my opinion if you are doing a pre-flight check, there is no point doing it unless it is pre-FLIGHT. Just about every other system on the aircraft got tested right up to when you boys arrived at the aircraft, but quite rightly you tested them again. (The whole point of 'us' testing systems was to pre-empting failures before they could impact the departure time).
If you even bothered to read what I wrote "But the 'trainers' often used to come seek me out in the hangar and .....confer about various system quirks and nasties....". I never suggested that anyone but the trainers themselves wrote the tech refreshers; but several of the guys (not you, obviously) waited 'til I was back from leave etc to ask away over coffee about some specific system QUOTE quirks and nasties UNQUOTE they figured I would know about and could use in their refresher.
Or perhaps you are suggesting that I am hallucinating or worse?
Dude
Quote:
| This was not very popular with the crews and the ground engineers were persuaded to test the ignitors before presenting the aircraft for service. However due to the engine starting Fuel Pump switching, this resulted with a small fire in the hanger, and so the crews were back to starting on Lh or RH ignitors. |
In any case as far as the 'ground engineers' doing the check of the ignitors, in my opinion if you are doing a pre-flight check, there is no point doing it unless it is pre-FLIGHT. Just about every other system on the aircraft got tested right up to when you boys arrived at the aircraft, but quite rightly you tested them again. (The whole point of 'us' testing systems was to pre-empting failures before they could impact the departure time).
Quote:
| No dude we never came to see you boys for the "Pilots Tech Refresher" as we always had to keep those lectures very simple as otherwise the pilots would go to sleep. |
Or perhaps you are suggesting that I am hallucinating or worse?
Dude
Last edited by M2dude; 18th Jan 2011 at 07:27 .