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FUEL FU/FOB DISCREPANCY recommendation
The part I like is the recommendation for mandating the pin change to the Flight Warning Computer programming to present an amber warning message when Fuel Used + Fuel on Board compared to Initial Fuel on Board at Departure exceeds 3500 Kg.:ok:
The part I don't like is that this capability was already in the FWC, but disabled:confused: |
RatherBeFlying,
Not entirely true: The FU/FOB calculation is done in the FCMCs, and there only at standard 9 and above. FCMC 9 came up sometime late 2001, I seem to remember. You only need to modify the FWC to make it "responsive" to the information from the FCMCs. BTW: As of 2006, you need to have this warning function activated to perform ETOPS... Cheers, J.V. |
In asserting that the Portuguese authorities have laid "all the blame on [the crew] doing a check list from memory", Mac_Scott is, I believe, misreading their report, a report which appears eminently comprehensive and fair to me.
Mac is right when he points out that, as usual, a whole chain of events led to the emergency. However, the Portuguese investigators, in their report and particularly in their recommendations, draw attention to deficient training of aircrew in fuel leak detection and to inadequate provision of warning systems to alert crew to abnormal fuel situations. Certainly, had the Air Transat crew referred to their Quick Reference Handbook when dealing with the fuel imbalance they might have noticed the caution not to follow the procedure in the case of a suspected fuel leak - but this was only one of the events in the chain. What shook me (SLF) most about this incident at the time - and still does - was the fact that the crew of a modern airliner on a long-haul flight had only 53 minutes notice of total fuel exhaustion. Rockhound |
Pilot error blamed-Air Transat
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OK, guys, I read the report. This is an ADvertent erasure of my previous post:\
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Original post deleted: Thread now merged, sarcy comment superfluous.
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For Mac:
You are being overly kind to the crew. After reading all 103 pp. of the report, my conclusion is that the Portuguese are also being overly kind. To begin, one of my old instructors said "A superior pilot is one who uses his superior judgment to avoid having to use his superior skill." This crew failed that directive. I don't understand why the crew felt the need to use a crossfeed valve when they didn't understand what was going on. Unless there was significant aerodynamic evidence, i.e. one wing very heavy, there was no urgency to cross feed. This is one of the reasons why regulators now ensure that cross feed is only done by very purposeful actions of the crew. There should be no remotely normal situation, with all engines operating, when a lateral imbalance gets out of hand. Once one of the engines is out, any half competent multi engine crew should be able to work out that the dead engine side will be heavy. Until that is clear, why break the isolation of the two sides? "Computer malfunction" suspected is a pure cop out. If it was a computer malfunction, there would be no reason to cross feed, unless the crew suspected that the computer had performed some side to side transfer. In that case, cross feed is an uncontrolled reaction to an undiagnosed situation. The crew made a bad situation dire by lack of basic airmanship. (What ever happened to "dead foot - dead engine" and the corresponding effect on heavy wing?) Nevertheless, once they had placed themselves in such a glider situation, they did not need the altitude they kept approaching Lajes. In their defense, I have been to Lajes at night, and you really can't see anything until you are almost lined up on the runway. (The lights have some directionality, and there is high ground - not a cliff, but a rise - north of the runway). Still, 13,000 feet up at 8 miles distance suggests that they could have planned their final approach a little better. They had time to do the old descent vs. distance calculation in their minds when they could see their stabilized descent rate. As an ex-military pilot, perhaps the oft practiced calculation of altitude needed to get to one of: 1. Overhead on runway heading at 2 mins. worth of altitude, or 2. Downwind at 1 min. worth of altitude plus a buffer to drop gear and flap, or finally 3. Join on base at something less than 1 minute of altitude is too simplistic for an airline crew long separated from such thoughts. Still, it does not show a good appreciation of time/altitude/distance to get so close so high. They did, however, scrub their altitude and speed successfully. 200 K over the threshold is not a terrible result. However, in light winds there does not appear to be a good reason to hammer the gear onto the ground as hard as they appear to have. Full braking was perhaps their best decision. I'm not at all impressed by this crew. Obvious comparisons are to the crew of an Air Canada 767 glider which successfully landed on a 6500' runway from over 100 NM out, or the celebrated DC-10 pilot who saved most of the passengers after physically losing an engine and all flight controls. The accident report focuses heavily on training re the computer pages and fuel imbalance situations. It appears that the investigators have accepted that airline crew are essentially automatons. This line of thinking will eventually lead to robot airliners. Only recently a fellow engineer told me that the high rate of human error means the machine must avoid human input at all times. Crews who show the lack of airmanship and understanding of mechanical systems evident here reflect badly on our community. |
plt_aeroeng
"they did not need the altitude they kept approaching Lajes." "Still, 13,000 feet up at 8 miles distance suggests that they could have planned their final approach a little better." "They had time to do the old descent vs. distance calculation in their minds when they could see their stabilized descent rate. " Are you out of your mind????? "As an ex-military pilot" OK, I see... Hasn't your old instructor also told that your better off losing extra altitude than... not making the field? |
Transat pilot flying high in popular opinion
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plt_aeroeng
It's very easy for you talk the talk of a superior pilot whilst sat at your computer. In the cold light of day and especially with the benefit of hindsight everyone will question why they chose to cross feed as it's obvious that they should not have done. At the time that the imbalance was noticed they were already trying to fault find a fault which was not covered in the QRH and like the fuel leek fault one that they had not previously experienced in the sim. This was obviously enough to have hampered their thought process and made them doubt the ECAM. You must also remember that the Air France pilots did exactly the same thing. "Still, 13,000 feet up at 8 miles distance suggests that they could have planned their final approach a little better" I would have thought it was much better to go for best glide range arrive high and then lose the height whilst preparing for the landing rather than increasing your workload trying to accurately plan your glide angle only to find that you've c**cked up and end up in the drink. "200 K over the threshold is not a terrible result" I would have though that it was very close to the stalling speed for an A330 with only slats deployed. A very good result I would imagine. "However, in light winds there does not appear to be a good reason to hammer the gear onto the ground as hard as they appear to have" When you consider that they had no flaps, no spoilers, no reverse thrust, no autobrake, no antiskid limited pitch control and no second chance I would of thought that getting the thing down was all that mattered. Perhaps a superior pilot such as yourself would have managed to do a perfect landing and controlled the braking sufficiently to allow the aircraft to coast to the gate, however I think that they did a stunning job of getting themselves out of the mess that they got themselves into. I'm only a wanabbie so maybe my thoughts are a little off the mark, and if so I apologise. I'd be very interested to hear if any line pilots agree with me. |
Well I agree with you Sky Wave.
That crew were let down by Airbus, Rolls, their own engineers their sim trainers and themselves. I wouldn't like to try that glide. Aside from the practical challenges of it, imagine the fear, stress, guilt, panic and embarresment they must have been feeling. |
plt_aeroeng
Out of order... Once the Engines had flamed out, I think the crew did exceptionally well. Interesting report, shame about no FDR for the glide in! If you have not flown a modern Airbus, they are fine when everything works. However, once you get to Emer Elec Config, life gets quite hard, but more significantly very different to normal ops. We practice it in the Sim - but that's with the engines working. I have also done, in the Sim, (successfully) the glide approach and landing - but with an APU, and having planned it. This crew at night, with most systems not working (remember we are talking a FBW aircraft here, with the FBW system in it's final degraded mode short of packing up), got the aircraft down and all OK. It doesn't get much worse than this in a FBW Airbus, short of total disaster... and cannot be compared to a Boeing in this situation. I also flew the A340, and an early turnback, and dumping required caused a number of "anomalies" to occur e.g. it failed to actually dump while this Trim Xfr was going on, despite the pretty screens showing it dumping (just the quantity did not reduce!). Hopefully the system has been improved, but when you have computers shifting fuel around largely at their whim, this will mask some of your basic observations / analysis. IMHO that went some way to recover the siutation that they did, to be fair, contribute to in the first place. These things happen - let's learn, not 20:20 hindsight sniping at the crew. Could be you next time? NoD |
Will they now be asked to hand the awards back?
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NoD you said
...in it's final degraded mode short of packing up |
Interested to see the rates of descent. 1000-1100 fpm gliding to field. 1700-2000 during orbit, then 1800 fpm when established on final approach.
Would these be typical for most modern jet aircraft ? (I imagine the A330 makes a particularly good glider ?) |
Smurfjet
...in it's final degraded mode short of packing up Whatever, the next degrade for FBW is "nil"! You do now have Rudder and Pitch Trim... It's flyable, and some people practice that that to landing - but with engines <G> NoD |
On an extremely popular, funny, and smart TV show the Captain Piché will be one of the main guests and will be interviewed and humored.
Sunday 8pm - 10pm Radio-Canada le commandant Robert Piché, http://radio-canada.ca/television/toutlemondeenparle/ |
Gumbi:
After rereading the report, I agree with you: the crew did do a 360 before landing (P 8), and thus did handle their descent profile well. In any case, I had no real issues with their approach to Lajes, my primary point was their actions before the double flameout. Sky Wave: The quote was from early student days being told what a fool I was, and it stuck. I stand by my position that there is a need for reasoning using basic airmanship. This should have suggested to the crew that crossfeed was a bad idea until either they better understood what was going on, or the imbalance got so bad that control became difficult. My note re 200K over the threshold should have been interpreted as being a good result after the previous flight path. However, if an A330 is near stall at 200K, why did it float 1,800 feet during the first bounce? I do accept that with the very degraded flight control mode, it may be unreasonable to expect a smoother landing. Just as a comment, I never suggested that I personally should be regarded as a superior pilot. Given that I have never had to practise a glider approach in a large aircraft, who knows whether I would have displayed superior skill. The real point is that judgment is generally more important than stick and rudder skill. Still, other large aircraft crews in glider situations seem to have done at least as well, perhaps better, and this is really the standard. I do think that the press reports describing the crew as "heroes" is somewhat excessive. Nigel: Perhaps you are right, in that modern aircraft do get very ropy with systems out. (Although - what about the DHL crew who suffered missile damage ex Baghdad, and successfully brought the aircraft back?) The real point, as I suggested, was the period before both engines flamed out. Del Prado: Fair analysis, although as Gumbi has pointed out, one would not want to guess wrong on final. Up to final, it should be relatively straightforward to predict altitude at destination. However, modern jet aircraft do have very large fans. With no fuel to turn them, these tend to worsen glide performance. |
Who is really at fault?
I noticed in the various postings since the release of the report some individuals have taken sides as to who was at fault and why. Granted I did not read the report (loss of concentration) and this may have been covered. I have spent the last 35 years as an assurance engineer. I have seen how airframe manufacturers skim over potential problems due to time constraints or financial constraints and in some cases not wanting to follow the input of assurance engineers like myself.
This problem did not start at 35,000 feet over the Atlantic. It did not start in the Air Transat maintenance facilities at Mirabel, Quebec. It started at the Rolls Royce facility in (I assume) Derby, England. Had a proper maintainability program been implemented by Rolls Royce they wold have prepared a design checklist. One aspect of this checklist would be directed at parts or assemblies that could be installed backwards. In the case of the Air Transat engine this would include the fuel line and the hydraulic line both of which could be installed backwards. It is obvious that such a checklist was never prepared. Since the parts could be installed backwards the technical manual for the engine should have contained a cautionary note telling the mechanic that caution should be taken when installing the respective lines. If the line(s) was/were installed incorrectly the design clearance between the two lines would close up allowing one line to abrade on the other resulting in a leak and in the case of the Air Transat engine total structural failure of the fuel line. This problem had been experienced on both General Electric and Pratt & Whitney engines resulting in minor leakage that was discovered during inspection of the engine and pylon support. Both companies issued ADs outlining the problem and providing detailed instruction relative to establishing the clearance between the two lines as well as periodic checks to see if the clearance had closed up. This happened long before the Air Transat incident so Rolls Royce should have known about the potential for the same type of incident on their engines. I don’t have access to Rolls Royce tech manuals and if any of the readers of this forum do please check to see how Rolls Royce is handling this situation. According to my sources Air Transat took delivery of a brand new A-330 after the Atlantic Glider incident and during receiving inspection they found that the hydraulic and fuel lines were contacting each other. :E :E |
His book came out 2 years ago and I got a copy and got it autographed by him at a book signing.
He was quite talkative considering the legal stuff was going on. This detailed conversation wouldn't have happened in the states. Robert Piché aux commandes du destin http://images.amazon.com/images/P/27...CMZZZZZZZ_.jpg http://www.amazon.ca/exec/obidos/ASI...405940-4644328 |
Here are plots from the official Incident report
Glide data from the moment the plane became a glider until "landing" http://www.airdisaster.com/user-uplo...236TableV2.gif Distance and Speed vs Time http://www.airdisaster.com/user-uplo...t236Figure.gif Speed, Glide Ratio (10x), and Vertical Rate (fpm) http://www.airdisaster.com/user-uplo...236Figure2.gif I'm surprised they were able to get an initial glide ratio of 24 which is very high !! I was expecting 17 or less. Note: The distance and speed is obtained from radar data; in other words it's the radial distance to the radar. |
I've just seen a program on TV about this with the normal media 'hero worship'.
Journo's love a good story, facts are sometimes inconveniences that have to be ignored. Heroes sell papers etc You WANT heroes - then look to Sioux City, those guys were heroic. Hero is a most over-used term these days. Fact: the crew were dealt a really nasty incident. Conjecture: You could argue that this fell outside the checklist. BUT am I wrong in thinking that blind, slavish acceptance of checklist is WRONG? If it isn't then you've made the case for the trained monkey instead of individuals who do LOFTs, CRM, Tech Refreshers, Line Checks etc etc. It became obvious early doors that the drill wasn't making the situation better. Surely any thinking person can differentiate between a fuel imbalance and a leak. Fuel imbalance IMPROVES when you take action, Fuel LEAK doesn't. My old time military checklists used to add a phrase along the lines of: This checklist constitutes the best advice currently available but may have to be modified and is no substitute for sound judgement and good airmanship (can't remember the exact phrase). When do you STOP feeding a fuel leak? It's NOT brain surgery. You're in the middle of the pond and your crossfeed is open and downstream fuel is disappearing too damn quick. So, lets just keep going until it's empty? Sound judgement and good airmanship? I don't think so. Given they were IN the position, they did well to get to land. Wouldn't any of you made the same decision given the lack of noise? This to me, smacks of slavish following of checklist without any thought of 'what are the implications of what I'm doing?'. Poor CRM and poor judgement. Smacks of some more heroes - Kegworth. Personally, my view is that had the questions been asked, and the gauges been viewed and interpreted, they could have landed at Santa Maria with an engine running. OK, I'm now ducking to avoid incoming. It's incidents like this of 'heroes' that remind me of the Viscount that ran out of noise just short of Bournemouth a few years back. Due to fuel gauge problems and a failure to reconcile fuel uplift, this crew ran out of fuel short of their DESTINATION let alone their ALTERNATE. They flopped into a field and everybody got out. The passengers clapped as the pilots came out of the cabin, the press hailed them as 'HEROES'. I rest my case. The Edit: Marks have been deducted for spelling and grammar- apologies for the stuff I've missed. |
LZ
One aspect of this checklist would be directed at parts or assemblies that could be installed backwards. In the case of the Air Transat engine this would include the fuel line and the hydraulic line both of which could be installed backwards The problem was a properly documented RR mod package, which was only half incorporated (some pre-Mod bits and some post-Mod). The problem was not really RR's. It was with the procedures (or lack of) when the engine change occurred. It was not helped by some of the contractual arrangements and expectations in the "pool" engine arrangments, and who was responsible for incorporating mods etc. NoD |
4 u space-cadettes out there, one more figure, for the gipper ...
Air Transat 236's last 31 minutes just as the 2 engines were starving for fuel. He did very good stable gliding at the beginning and on final to the runway !! What I was mainly interested in was the Glide Ratio which is rarely ever mentioned. In this case it was 24 which is very good/high (but i was expecting 17). A well designed glider-plane will do 40 - 50 (or 40 miles distance whilst losing only 1 mile in altitude). From 10000ft you could glide 100 miles without any power on these professional gliders. For a Boeing or Airbus it could glide 100 miles from an altitude of 20000 feet without power !! He seemed to have glided at approx 250 knots ground speed (nautical miles per hour) (or 200 knots indicated airspeed). So next time you have to glide-in your Boeing or Airbus make sure you keep that airspeed of 200 knots on the instrument !!! Too fast or too slow and you lose more altitude !!!!! Glossary: min: minutes nm: nautical miles FL: Flight Level (almost exactly same as altitude) Speed: speed towards radar on island Descent: vertical speed in feet per minute Glide Ratio: Forward speed divided by downward speed http://www.airdisaster.com/user-uplo...236Figure3.gif |
Now let me see, which way do these parts go?
To: NigelOnDraft
I don't think anybody has said that anything was installed backwards. If your post was making this assumption, than a very elequant post it is, but nothing to do with this incident. That’s the story I got from my sources and I’m sticking with it. :E :E |
Just the facts, Lu
Mr Z, you seem very insistent on blaming the engines...a previous bad experience ?
Rereading the official report, page 16 : In fact, it’s a requirement for the airline who installs the core engine to check its configuration and receipt and ensure that it complies with the manufacturers specifications. and on page 18 : the scratches and scores were directionally aligned and that they could have been caused from repeated contact from a blunt instrument, such as a screwdriver being inserted be-tween the tubes in order to force a clearance between them. There were no cracks initiated from the score or scratch marks So, it appears to me that someone inspected the (incorrect) arrangement of tubes etc, and attempted to force them into a suitable clearance. On page 17 : It was evident that the interference and chafing occurred due to the mismatched installation of the post-mod fuel tube (P/N: FK30383) and pre-mod hydraulic tube (P/N: LJ51006). The Mod in question, SB72-C625 says (on page 7 of the SB) : Interchangeability of Parts : (1) It is essential that the parts are fitted as a set. So. What are the facts about this "backward pipe fitting" story? |
Don't we live in a BLAME culture?
The crew had ONE failure - be completely clear about it. ONE failure should not cause the potential loss of the aircraft. Let's substitute the word RESPONSIBILITY for the word 'blame'. Given the HANDLING of their one failure, once it had resulted in the double hush - they then did quite well. When they shave in the morning they are looking at the people responsible for getting into the more serious situation in the first place. Computer fault, engine component failures, Murphy's etc aside - they were NOT the reason for a double flameout. The crew WERE. Remember a SINGLE component failure - isn't ETOPS based upon that? But, competently handled, it is SAFE. They are paid as professionals, trained as professionals, trusted by the pax as professionals and sadly didn't act like professionals UNTIL they ended up with no engines - then in many respects they redeemed themselves (out of sheer desperation probably, nevertheless everybody got out and I suppose that's the result that sticks in the travelling public's mind). It's really that simple. All the rest is moving air around at 37 degrees C. edited for grammar this time DD |
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