Flying to the Falklands
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I'm still concerned about the fly by wire in the Airboooooos. Have you read the AAIB report about the A340 which encountered a
little turbulence, the FBW decidedto go to alpha prot, firewalled the throttles and zoom climbed out of its assigned level, very nearly colliding with an A330?
I cannot see how we could EVER trust Airboooooooooooooos' control laws NOT to do something equally alarming with a receiver in contact.
I have serious doubts about what the A330 tanker FBW would decide to do when a receiver disconnects and gives the tanker a transient yawing moment and change in apparent drag.
little turbulence, the FBW decidedto go to alpha prot, firewalled the throttles and zoom climbed out of its assigned level, very nearly colliding with an A330?
I cannot see how we could EVER trust Airboooooooooooooos' control laws NOT to do something equally alarming with a receiver in contact.
I have serious doubts about what the A330 tanker FBW would decide to do when a receiver disconnects and gives the tanker a transient yawing moment and change in apparent drag.
That has now been addressed.
How about the pair of you cut and paste artistes making a useful contribution to this debate rather than just harping on about past statements I may have made?
A week is a long time in politics.......and the change of AR emphasis following recent experience must equally be addressed.
How about the pair of you cut and paste artistes making a useful contribution to this debate rather than just harping on about past statements I may have made?
A week is a long time in politics.......and the change of AR emphasis following recent experience must equally be addressed.
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A week is indeed a long time in politics. However, it is doubtful whether any politician has made such a dramatic u-turn. If they had, their credibility would undoubtedly lie in shreds...
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Really...
BEags
I've been out of the AT/AAR game for a while now (and I was a truckie anyway) - BUT I think that the point about the 'Airbooos' doing its own thing with a receiver in contact was a point worthy of an answer.
Not that you didn't answer it, of course, but IMHO you did so in a cursory and dismissive, 'should know better', kind of way.
I'm sure your argument has substance (because, BEags, you are a guru to our entire community); but for the idiots amongst us, could you please explain the substance?
I have to say that, when I was flying the all-electric folding bomber, there were some 'really useful' features that one could have well done without...
Gadget
I've been out of the AT/AAR game for a while now (and I was a truckie anyway) - BUT I think that the point about the 'Airbooos' doing its own thing with a receiver in contact was a point worthy of an answer.
Not that you didn't answer it, of course, but IMHO you did so in a cursory and dismissive, 'should know better', kind of way.
I'm sure your argument has substance (because, BEags, you are a guru to our entire community); but for the idiots amongst us, could you please explain the substance?
I have to say that, when I was flying the all-electric folding bomber, there were some 'really useful' features that one could have well done without...
Gadget
mockingbird was merely quoting verbatim from something I once wrote on here regarding my concern at the possible response which Airbus FBW laws might generate when reacting to the short term perturbations which might result from receiver disconnects etc.
I'm told that such concerns have now been addressed. As have the roll control characteristics essential for AR operation.
The A330/340 'Atlantic Incident' is AAIB report 6/2001. The full report is at http://www.dft.gov.uk/stellent/group...ty_501275.hcsp
Here is an extract:
The A330 commander's report:
Both aircraft were in clear air as the A330 was slowly overtaking the A340 below it. The A330 commander stated that his aircraft was slightly to the right of the A340 and almost abeam it when he saw the A340's wings start to flex. At about that time he felt a bump, which he described as similar to entering a mountain wave. Five to ten seconds later there was another bump during which the A330's altimeter reading descreased by 200 feet. Immediately thereafter, the A330 commander heard a TCAS "climb climb" warning and he noted that the A340 TCAS symbol had changed colour to red on his navigation display. He looked out and down at the A340 which was some 200 to 300 feet to his left in a nose-up attitude and climbing steeply. The A340 passed through the A330's level before the commander had time to react to the TCAS warning and the TCAS was still issuing a "climb" instruction for a short while after the A340 had climbed above the A330. The commander continued to monitor the A340 visually and on TCAS. It appeared to reach an apogee above FL380 although by this time it had fallen behind the A330. Nevertheless, it was still laterally quite close to the A330's track so the commander altered copurse to the right to make space for the A340 to descend back to FL 360. After a short discussion with the A340 crew on VHF radio, the A330 commander broadcast a warning of severe turbulence on the common VHF frequency and then reported both the turbulence and the aircraft proximity (AIRPROX) occurrence to Shanwick on HF Radio. there were no injuries on board the A330 although there were spillages in the cabin.
The A340 commander's report
At FL 360 the A340 was 1000 feet below the maximum cruising level displayed on the Flight Management and Guidance System (FMGS). The commander was expecting a turbulence encounter around 59°N 20°W and when the aircraft first entered light turbulence he made a cabin announcement and switched on the seat belt signs. Shortly before the AIRPROX event he experienced moderate turbulence and noticed outside air temperature changes. Suddenly the aircraft began to climb, the Master Warning sounded and the autopilot self-disengaged as the aircraft exceeded the speed limit of 0.86 Mach. The indicated airspeed dropped below VLS (the lowest selectable) as the aircraft climbed and the commander took manual control of the aircraft because neither autopilot would engage. The crew subsequently reported the incident to Shanwick on HF radio and using their TCAS, they descended back to FL 360 in a safe area. At the time of the AIRPROX the commander estimated the aircraft were one mile apart laterally. After landing at New York the commander had the aircraft inspected by technical staff but no defects were found. There were no injuries on board the aircraft.
The commander could not remember the sequence of warnings but he did recall being unable to re-engage either autopilot which prompted him to make manual control inputs. He also remembered seeing an ‘Alpha Lock’ warning displayed on his Primary Flying Display.
I'm told that such concerns have now been addressed. As have the roll control characteristics essential for AR operation.
The A330/340 'Atlantic Incident' is AAIB report 6/2001. The full report is at http://www.dft.gov.uk/stellent/group...ty_501275.hcsp
Here is an extract:
The A330 commander's report:
Both aircraft were in clear air as the A330 was slowly overtaking the A340 below it. The A330 commander stated that his aircraft was slightly to the right of the A340 and almost abeam it when he saw the A340's wings start to flex. At about that time he felt a bump, which he described as similar to entering a mountain wave. Five to ten seconds later there was another bump during which the A330's altimeter reading descreased by 200 feet. Immediately thereafter, the A330 commander heard a TCAS "climb climb" warning and he noted that the A340 TCAS symbol had changed colour to red on his navigation display. He looked out and down at the A340 which was some 200 to 300 feet to his left in a nose-up attitude and climbing steeply. The A340 passed through the A330's level before the commander had time to react to the TCAS warning and the TCAS was still issuing a "climb" instruction for a short while after the A340 had climbed above the A330. The commander continued to monitor the A340 visually and on TCAS. It appeared to reach an apogee above FL380 although by this time it had fallen behind the A330. Nevertheless, it was still laterally quite close to the A330's track so the commander altered copurse to the right to make space for the A340 to descend back to FL 360. After a short discussion with the A340 crew on VHF radio, the A330 commander broadcast a warning of severe turbulence on the common VHF frequency and then reported both the turbulence and the aircraft proximity (AIRPROX) occurrence to Shanwick on HF Radio. there were no injuries on board the A330 although there were spillages in the cabin.
The A340 commander's report
At FL 360 the A340 was 1000 feet below the maximum cruising level displayed on the Flight Management and Guidance System (FMGS). The commander was expecting a turbulence encounter around 59°N 20°W and when the aircraft first entered light turbulence he made a cabin announcement and switched on the seat belt signs. Shortly before the AIRPROX event he experienced moderate turbulence and noticed outside air temperature changes. Suddenly the aircraft began to climb, the Master Warning sounded and the autopilot self-disengaged as the aircraft exceeded the speed limit of 0.86 Mach. The indicated airspeed dropped below VLS (the lowest selectable) as the aircraft climbed and the commander took manual control of the aircraft because neither autopilot would engage. The crew subsequently reported the incident to Shanwick on HF radio and using their TCAS, they descended back to FL 360 in a safe area. At the time of the AIRPROX the commander estimated the aircraft were one mile apart laterally. After landing at New York the commander had the aircraft inspected by technical staff but no defects were found. There were no injuries on board the aircraft.
The commander could not remember the sequence of warnings but he did recall being unable to re-engage either autopilot which prompted him to make manual control inputs. He also remembered seeing an ‘Alpha Lock’ warning displayed on his Primary Flying Display.
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Mr Massingbird
Shame on you Sir.
All that I asked Mr BEagle to do was to elucidate us masses - which he did.
Of course I still have questions as to why TCAS does not call for heading changes, when lateral separation (even under MNPS, if my long-term memory is still functioning) is far greater than vertical. Admittedly, the incident in question took place outside radar coverage - but can you imagine the apoplexies in ATC if it had not?
I have an even bigger question as to why the aircraft captain of the A340 took 17 seconds plus to [section deleted on legal advice]...
But I didn't ask those questions, did I?
And BEagle answered the one that I did.
Gadget
All that I asked Mr BEagle to do was to elucidate us masses - which he did.
Of course I still have questions as to why TCAS does not call for heading changes, when lateral separation (even under MNPS, if my long-term memory is still functioning) is far greater than vertical. Admittedly, the incident in question took place outside radar coverage - but can you imagine the apoplexies in ATC if it had not?
I have an even bigger question as to why the aircraft captain of the A340 took 17 seconds plus to [section deleted on legal advice]...
But I didn't ask those questions, did I?
And BEagle answered the one that I did.
Gadget
mockingbird - sufficiently.
Captain G - lateral TCAS advisory commands are still some way off. But I'm sure that a current 'wide-body' pilot could explain why....
Captain G - lateral TCAS advisory commands are still some way off. But I'm sure that a current 'wide-body' pilot could explain why....
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Massingbird - for G0d's sake give it a rest!
Surely one of the most important skills a pilot (or manager) can have is the willingness to change his mind and his plans if the situation dictates.
Would you stay on track and fly through a CB just because that track is the one you filed for 4 hours ago? Or would you say that it was a good idea to re-assess the situation and choose an alternative route?
You may not agree with the opinions which BEagle chooses to hold (some will, some will not) but you surely have no grounds to criticise someone because he is open minded enough to change his point of view. From personal experience I found plenty of people on the VC10 fleet who had very fixed mindsets!
Personally, I would like to see new, European aircraft used rather than pretty-old, tired 767s however I would want those new aeroplanes to be capable of operating where needed.
Of course, there is no rule that says an aeroplane has to take of at max structural TOW, so if you are operating from shorter runways or those with lower load bearing capabilities you can go off with a lower fuel load at max REGULATED TOW.
I'm not sure off the top of my head how the 767 and 330 compare with regard to payload/fuel available to offload - I am sure BEagle can tell me. But if the 330 will operate out of the same places as a 767 with the same fuel load (but have the option to carry more when the runway allows) then is that level of flexibility not a welcome addition to the game?
Anyway - I still think that flying to the FI in the back of any RAF aeroplane is the sort of thing that should invite the interest of Amnesty International and the Red Cross!
Surely one of the most important skills a pilot (or manager) can have is the willingness to change his mind and his plans if the situation dictates.
Would you stay on track and fly through a CB just because that track is the one you filed for 4 hours ago? Or would you say that it was a good idea to re-assess the situation and choose an alternative route?
You may not agree with the opinions which BEagle chooses to hold (some will, some will not) but you surely have no grounds to criticise someone because he is open minded enough to change his point of view. From personal experience I found plenty of people on the VC10 fleet who had very fixed mindsets!
Personally, I would like to see new, European aircraft used rather than pretty-old, tired 767s however I would want those new aeroplanes to be capable of operating where needed.
Of course, there is no rule that says an aeroplane has to take of at max structural TOW, so if you are operating from shorter runways or those with lower load bearing capabilities you can go off with a lower fuel load at max REGULATED TOW.
I'm not sure off the top of my head how the 767 and 330 compare with regard to payload/fuel available to offload - I am sure BEagle can tell me. But if the 330 will operate out of the same places as a 767 with the same fuel load (but have the option to carry more when the runway allows) then is that level of flexibility not a welcome addition to the game?
Anyway - I still think that flying to the FI in the back of any RAF aeroplane is the sort of thing that should invite the interest of Amnesty International and the Red Cross!
moggie - thanks. I thought that certain needles were getting stuck in certain grooves, to use an old vinyl metaphor.
Re. the payload/range query, I've done some data reduction using open source material. Unfortunately I don’t know how to post .jpg images into PPRuNe posts, so you’ll have to construct your own FSTA payload/range graph from the following information obtained from the manufacturers’ publications but not factored for AR role-configured aeroplanes:
X-axis (range) from 0 to 10000 nautical miles, Y-axis (payload) from 0 to 60 tonnes. For the A330, the x,y curve is (0,50), (4000,50), (9000, 0) and for the B767 it’s (0,41.68), (3709, 41.68), (5854, 21.73), (6748,0).
If you construct this graph, it will be readily apparent that the A330 offers a considerable payload range advantage over the B767, particularly at ranges in excess of 5700 nm. For example, it would be possible for an A330 to fly non-stop direct from Brize Norton to the Falkland Islands, a great circle distance of 6800 nm, carrying at least 100 passengers whereas a B767 would be unable to fly the route non-stop with any payload. The A330 has a baseline seat fit of 293 seats, 30 B-class at 40” pitch and 263 Y-class at 32” pitch. British Airways operates the B767 in a variety of seating configurations; typically in ‘Longhaul Regional’ configuration it is fitted with 32 B-class ‘Club World’ seats at 43” pitch and 183 Y-class ‘World Traveller’ seats at 32” pitch. However, other B767-300ER configurations include 24 B-class seats at 38” pitch and 245 Y-class at 32” pitch, a total of 269 seats. The A330 cabin interior is considerably more spacious than that of the B767, allowing standard 21” width Y-class seats to be fitted in an 8 abreast configuration with 2 x 19” aisles, apart from the rearmost 5 rows which are fitted 7 abreast. The narrower cabin of the B767 means that seats and aisles of the same dimensions may only be fitted in 7 abreast configuration. Both aircraft offer substantial underfloor cargo areas without any compromise from AR fuel tanks. The maximum cargo volume available in the A330 is 4803 ft³, using 26 LD3 cargo containers, the most common container in use world-wide, plus 695 ft³ bulk cargo in the rear of the hold whereas the B767 offers a maximum volume of 4030 ft³, some 16% less. However, to achieve this the B767 needs to use 30 smaller LD2 containers plus 430 ft³ bulk cargo. Unlike the A330, the B767 cannot carry LD3 containers in side-by-side pairs.
Although British Airways Fact Book 2002 lists the maximum take-off weight of its B767-336 aircraft as 181.4 tonne, Boeing quotes the MTOW of the B767 aircraft as 186.9 tonne in 269 seat configuration. At ISA+15°C in still air at sea level, the B767 at 186.9 tonne requires a take-off field length of 10100 ft, whereas at its MTOW of 230 tonne under the same conditions, the A330 requires a take-off field length of 8300 ft. On such a 8300 ft runway under the same conditions, the B767 would be limited to a MTOW of 175 tonne.
For the AR role, on a North Sea ARA sortie upon which a full VC10K3 could offer 2:10 hours on task or a VC10C1K/K4 1:44 hours, a B767 with 73.1 tonne of fuel on take-off could offer 2:16 hours or an A330 with 111 tonnes 3:41 hours at the same assumed constant offload rate. Unlike the USAF’s KC-767A, the ex-BA 767s are not, according to the TTSC website, being offered with additional fuel. It has been alleged that the A330 faces infrastructural problems at certain bases from PCN/ACN and dimensional constraints; hence it is prudent to examine the A330’s capability if forced to operate from a base some 500 nm further from the ARA. In such a case it could still offer 3:16 hours on the same task, an hour more than the rival B767 and thus the purported deployability limitation of the A330 is clearly more than offset by its much greater AR capability.
It will be readily apparent that AirTanker’s Airbus A330-200 platform offers a markedly superior capability in both Air Transport and Air Refuelling roles when compared against the ex-BA Boeing 767-300ER proposed by TTSC even when deployed to a base 500 nm further from the ARA than that used by its competitor. It is also a far more modern aeroplane in all respects; however, the viability of its operation is inextricably linked to the business case presented by the bidding consortium. That is a highly sensitive commercial matter upon which I will make no comment whatsoever.
But getting back to the thread topic, I'm sure that anything which reduces the current transit time between the UK and the Islas Malvinas would be greatly appreciated by all!
Re. the payload/range query, I've done some data reduction using open source material. Unfortunately I don’t know how to post .jpg images into PPRuNe posts, so you’ll have to construct your own FSTA payload/range graph from the following information obtained from the manufacturers’ publications but not factored for AR role-configured aeroplanes:
X-axis (range) from 0 to 10000 nautical miles, Y-axis (payload) from 0 to 60 tonnes. For the A330, the x,y curve is (0,50), (4000,50), (9000, 0) and for the B767 it’s (0,41.68), (3709, 41.68), (5854, 21.73), (6748,0).
If you construct this graph, it will be readily apparent that the A330 offers a considerable payload range advantage over the B767, particularly at ranges in excess of 5700 nm. For example, it would be possible for an A330 to fly non-stop direct from Brize Norton to the Falkland Islands, a great circle distance of 6800 nm, carrying at least 100 passengers whereas a B767 would be unable to fly the route non-stop with any payload. The A330 has a baseline seat fit of 293 seats, 30 B-class at 40” pitch and 263 Y-class at 32” pitch. British Airways operates the B767 in a variety of seating configurations; typically in ‘Longhaul Regional’ configuration it is fitted with 32 B-class ‘Club World’ seats at 43” pitch and 183 Y-class ‘World Traveller’ seats at 32” pitch. However, other B767-300ER configurations include 24 B-class seats at 38” pitch and 245 Y-class at 32” pitch, a total of 269 seats. The A330 cabin interior is considerably more spacious than that of the B767, allowing standard 21” width Y-class seats to be fitted in an 8 abreast configuration with 2 x 19” aisles, apart from the rearmost 5 rows which are fitted 7 abreast. The narrower cabin of the B767 means that seats and aisles of the same dimensions may only be fitted in 7 abreast configuration. Both aircraft offer substantial underfloor cargo areas without any compromise from AR fuel tanks. The maximum cargo volume available in the A330 is 4803 ft³, using 26 LD3 cargo containers, the most common container in use world-wide, plus 695 ft³ bulk cargo in the rear of the hold whereas the B767 offers a maximum volume of 4030 ft³, some 16% less. However, to achieve this the B767 needs to use 30 smaller LD2 containers plus 430 ft³ bulk cargo. Unlike the A330, the B767 cannot carry LD3 containers in side-by-side pairs.
Although British Airways Fact Book 2002 lists the maximum take-off weight of its B767-336 aircraft as 181.4 tonne, Boeing quotes the MTOW of the B767 aircraft as 186.9 tonne in 269 seat configuration. At ISA+15°C in still air at sea level, the B767 at 186.9 tonne requires a take-off field length of 10100 ft, whereas at its MTOW of 230 tonne under the same conditions, the A330 requires a take-off field length of 8300 ft. On such a 8300 ft runway under the same conditions, the B767 would be limited to a MTOW of 175 tonne.
For the AR role, on a North Sea ARA sortie upon which a full VC10K3 could offer 2:10 hours on task or a VC10C1K/K4 1:44 hours, a B767 with 73.1 tonne of fuel on take-off could offer 2:16 hours or an A330 with 111 tonnes 3:41 hours at the same assumed constant offload rate. Unlike the USAF’s KC-767A, the ex-BA 767s are not, according to the TTSC website, being offered with additional fuel. It has been alleged that the A330 faces infrastructural problems at certain bases from PCN/ACN and dimensional constraints; hence it is prudent to examine the A330’s capability if forced to operate from a base some 500 nm further from the ARA. In such a case it could still offer 3:16 hours on the same task, an hour more than the rival B767 and thus the purported deployability limitation of the A330 is clearly more than offset by its much greater AR capability.
It will be readily apparent that AirTanker’s Airbus A330-200 platform offers a markedly superior capability in both Air Transport and Air Refuelling roles when compared against the ex-BA Boeing 767-300ER proposed by TTSC even when deployed to a base 500 nm further from the ARA than that used by its competitor. It is also a far more modern aeroplane in all respects; however, the viability of its operation is inextricably linked to the business case presented by the bidding consortium. That is a highly sensitive commercial matter upon which I will make no comment whatsoever.
But getting back to the thread topic, I'm sure that anything which reduces the current transit time between the UK and the Islas Malvinas would be greatly appreciated by all!
Last edited by BEagle; 4th Sep 2003 at 01:01.
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BEagle - thanks for that. I think I can get all I need without drawing graphs.
Basically, if I read you right, as long as the runway can hold the A330's weight then for a given runway length an A330 can carry substantially more fuel to the chaps who need it - full stop.
Therefore there is almost 50% greater offload capability with the 330 than the 767.
The non-stop to FI makes a HUGE difference! By the time you allow for descent and departure you have saved at least an hour. Add in the best efforts of the movers at ASI and that goes up to 3-4 hours. That is a lot of airframe fatigue life over the next 20 years.
Reminds me of the plann Rolls Royce floated for the VC10 in 1986 (I think). Re-engined with the V2500 there would have been guaranteed:
10% more thrust
Significantly reduced noise (and how!)
Better reliability and
Minimum 30% fuel saving (projected 35-40%)
That fuel saving would have guaranteed direct to Dulles every day of the year and probably direct to Calgary from Gutersloh every day, too (no more KEF!).
RR said that the design, engineering and purchase of engines and ground equipment would have been paid for in 5 years by the guaranteed fuel saving.
Of course, the RAF could not be seen to spend money to save money so they allowed the offer to pass by.
How is the Conway these days?
Basically, if I read you right, as long as the runway can hold the A330's weight then for a given runway length an A330 can carry substantially more fuel to the chaps who need it - full stop.
Therefore there is almost 50% greater offload capability with the 330 than the 767.
The non-stop to FI makes a HUGE difference! By the time you allow for descent and departure you have saved at least an hour. Add in the best efforts of the movers at ASI and that goes up to 3-4 hours. That is a lot of airframe fatigue life over the next 20 years.
Reminds me of the plann Rolls Royce floated for the VC10 in 1986 (I think). Re-engined with the V2500 there would have been guaranteed:
10% more thrust
Significantly reduced noise (and how!)
Better reliability and
Minimum 30% fuel saving (projected 35-40%)
That fuel saving would have guaranteed direct to Dulles every day of the year and probably direct to Calgary from Gutersloh every day, too (no more KEF!).
RR said that the design, engineering and purchase of engines and ground equipment would have been paid for in 5 years by the guaranteed fuel saving.
Of course, the RAF could not be seen to spend money to save money so they allowed the offer to pass by.
How is the Conway these days?
Yes - you've got it in one, moggie! But the offload comparison in my example assumes a transfer rate of 20 tonne per hour, so the comparison would change slightly with different transfer rates.
With 20-20 hindsight, the V2500 option would have been a good one for the Vickers FunBus.
How is the Conway these days? As I'm sure even the TriShaw mates will agree - B£OODY NOISY!!
With 20-20 hindsight, the V2500 option would have been a good one for the Vickers FunBus.
How is the Conway these days? As I'm sure even the TriShaw mates will agree - B£OODY NOISY!!
Last edited by BEagle; 26th Aug 2003 at 20:33.
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Noisy but nostalgic! My parents still live near BZN and I can't help looking up everytime I hear that VERY distinctive sound as they pass over.
I used to love that "whooosh" and the shove in the back as the N1s passed 93% on a rolling take off. Inside, up the front is the only sociable place to be when a VC10 goes off, mind you.
I used to love that "whooosh" and the shove in the back as the N1s passed 93% on a rolling take off. Inside, up the front is the only sociable place to be when a VC10 goes off, mind you.
