Turbulence over British Airways' hairy flight

[tf51d 284]

I'm not sure if you've read the article posted at the top of the thread or any of our other comments on the fuel management of that flight, but they actually had about 10000lbs of fuel aboard when they landed. The issue that caused them to declare the emergency was the handling of the fuel pumps and crossfeeds that left most of it inside a tank that they thought they couldn't use. 10000lbs is probably about 40 minutes of flight time left on the three engines. They declared the emergency and said they "couldn't go around" because tanks 1, 3 and 4 each only had about 1200lbs left while the captain didn't know how to get at the 6400lbs in tank 2. The 6400lbs could have been used up if the captain had opened the crossfeed valves and shut off all but the Tank 2 override pumps while enroute instead of letting the system go Tank-to-Engine with fuel still in Tank 2. If he had used up the 6400lbs earlier, he would have had enough in the remaining tanks to land without declaring an emergency.Yes I had read it. Since the pilot didn't know that fuel was usable it has to be considered unusable. For the sake of argument lets say it was. I just tried flying on PMDG BA 744 on 3 engines with 12000 lb fuel (Wasn't able to get any closer using PMDG loader) 2/3 passenger weight, which is approximately what they had 351 passengers. I set up at 29000 ft (Their stated altitude)plotted a course with FMC to EGLL from KLAX. I ran out of gas 27 minutes into the flight. So with 10000 lb like they had it would have been something like 24 min of fuel. Say though they were able to stretch it to 40-45 minutes. They still needed to fly 140+nm further to make it to LHR. At the lower altitude and speed, that would have used up about 20 minutes of that time, this still puts them in the hole to meet the reserve fuel requirement. No matter which way you slice it they made a bad decision! The fact they didn't know the extra fuel was usable also brings up another question. Why didn't they know? Didn't their maintenance staff know this could be done? Couldn't they have contacted Boeing for technical advice on the issue. There are a lot of open questions the FAA and the British authorities are going to want answerered.

[KevinAu 441]

>The fact they>didn't know the extra fuel was usable also brings up another>question. Why didn't they know? Didn't their maintenance staff>know this could be done? Couldn't they have contacted Boeing>for technical advice on the issue. There are a lot of open>questions the FAA and the British authorities are going to>want answerered. Less than superior systems knowledge is generally the reason why. And that's very common. Pilots are human. Chew on that the next time you step onto a plane. But you're still missing the point. The original calculations in the decision process showed that they had sufficient fuel if everything was done properly and the winds were as predicted. But because of a failure on the pilots' part to push the right buttons and turn the right knobs, and less favorable winds than forecasted, part of the fuel they planned on using became "unusable" in their minds and they burned more gas than anticipated from the winds. So they landed at Manchester. You paint the entire situation with a broad swath of "It's a mistake! Period!" but in reality, there were several factors here which led to the incident. Each accident is a chain of events, as far as Joe Public seems to be concerned, the emergency landing is the "accident" here. Breaking of just one link in the chain prevents the accident. Working backwards, the links here are: 1. If they had properly configured the fuel system to burn off all the Tank 2 fuel, the accident would not have happened. 2. If the winds panned out as forecasted, the accident would not have happened. 3. If they landed somewhere in the US the accident would not have happened. 4. If the engine had not stalled the accident would not have happened. 5. If the pilots did not roll out of bed that morning the accident would not happened. For some reason though, you seemed to be pretty focused on number 3 as the one and sole cause of the accident. It is not. It is just one of five equal links in the chain. 1, 3, and 5 were all well within the pilots' control. I find the most fault on the part of the pilots from 1, if they had properly configured the system, they may still not have made EGLL because of the winds, but at least it would not have been a critical situation when landing at the alternate. I see nothing wrong with the decision at 3, since at that time, the available information showed that the flight could be continued legally and safely. They did not know at that point that they were going to screw up the fuel configuration on the way over or that the winds aloft ended up worse than predicted. If they had the prescience to know that, then they probably would have broken the chain at 5, which is to not roll out of bed. Having to look at the possible ramifications of each decision at that point, landing at LA would have been the least attractive since they would have been stuck there with a broken plane, cause a delay for the passengers, and cost the company in reaccomodation and penalties, when they could have continued to EGLL, which the plane was perfectly legal and capable of, and avoid all those hassles.

[tf51d 284]

Working backwards, the links here are: 1. If they had properly configured the fuel system to burn off all the Tank 2 fuel, the accident would not have happened. 2. If the winds panned out as forecasted, the accident would not have happened. 3. If they landed somewhere in the US the accident would not have happened. 4. If the engine had not stalled the accident would not have happened. 5. If the pilots did not roll out of bed that morning the accident would not happened. For some reason though, you seemed to be pretty focused on number 3 as the one and sole cause of the accident. It is not.The reason I'm focused on #3 is while proceeding to LHR may have been safe assuming everything went as planned, the reduced margin for error as demonstrated by the result, makes it not as safe as a closer alternative. That is why the FAA uses that term in the rule. That is what the FAA is going after them on! Had they landed at JFK fuel would had never been an issue. with an additional 5 to 6 hour reserve if they had to stay aloft for some reason!

[KevinAu 441]

Then there is no point in the rule that allows you to continue on the three engines. With your reasoning that continuing on three engines is reduced safety margin and therefore will always fail the "as safe" criteria because of, by definition, reduced safety margin, then the decision tree will always stop at that point. It makes the entire rule pointless. You will always stop at the closest airport. Don't crawl out of bed in the morning.

[tf51d 284]

>Then there is no point in the rule that allows you to>continue on the three engines. With your reasoning that>continuing on three engines is reduced safety margin and>therefore will always fail the "as safe" criteria because of,>by definition, reduced safety margin, then the decision tree>will always stop at that point. It makes the entire rule>pointless. You will always stop at the closest airport. >Don't crawl out of bed in the morning.No if the destination was say only 2 or 3 hours away leaving a reasonable margin for a reserve even if they ran into unexpected weather/headwind conditions, than it would be just as safe to contnue. To continue to almost max range (Under 3 Engine conditions) even if all the fuel was available and that was never an issue as shown, to have to rely on an accurate favorable weather forecast to make it is cutting that line too thin, to be gambling 351+ lives with, including your own! How many times has the weatherman been wrong? I was driving into work one day in NY and listening to the radio which said it was currently sunny and warm. Meanwhile, I was in one of the worst down pours I've ever seen! At least they got the warm part right!

[KevinAu 441]

>>No if the destination was say only 2 or 3 hours away leaving a>reasonable margin for a reserve even if they ran into>unexpected weather/headwind conditions, than it would be just>as safe to contnue. To continue to almost max range (Under 3>Engine conditions) even if all the fuel was available and that>was never an issue as shown, to have to rely on an accurate>favorable weather forecast to make it is cutting that line too>thin, to be gambling 351+ lives with, including your own!But by your own logic, how is continuing on across the country, to say JFK, as you've suggested, as safe as circling over the Pacific to dump fuel and land at LAX? Don't you have to cross some mountains and deserts to get there? How is flying over the Rocky Mountains and spending an hour or two over inhospitable terrain as safe as landing back at LAX?What is a reasonable margin for reserve fuel? Is it the amount you suggested earlier of 4-5 hours of gas in the tanks when you land? Is it 2-3 hours of gas in the tanks? Maybe two days worth of gas? Is it whatever the legal minimums is? You see, anything more than the legal minimums is called "gravy." They calculated that they met the legal amount of fuel required to get to EGLL on the three engines. How much more "gravy" should have been required above that? And if gravy was required, since when did business entities become required to provide gravy?The three engine rule, like a lot of other rules, is "gray." It is ambiguously worded, both allowing the pilot to make use of it, and allowing the FAA to go after a pilot for making use of it. Those guys could have been heroes or zeroes. They ended up zeroes. But they were zeroes for several reasons, not just the one you cite. It's a chain of events, all they had to do was break one link. The important thing in risk management is to avoid building a box that you cannot exit from. There is nothing wrong with letting a couple of sides of a box go up, since none of us would roll out of bed in the morning if our goal in life is to avoid all risks. The key is to realize the box it is you are making and not let the box close on you.

[tf51d 284]

But by your own logic, how is continuing on across the country, to say JFK, as you've suggested, as safe as circling over the Pacific to dump fuel and land at LAX? Don't you have to cross some mountains and deserts to get there? How is flying over the Rocky Mountains and spending an hour or two over inhospitable terrain as safe as landing back at LAX?In the article it was argued, dumping fuel isn't as safe as continuing on, I assume because of the possible risk of ignition as it flowed over the wings. Then there is the environmental impact of fuel being dumped in the ocean, which we all know the environmentalists would have a fit over! These arguments I can understand. They could have flown around LAX for a few hours like the JetBlue plane did. Since the main issue was fuel and they had plenty to traverse over the US, this was just as safe. If they did run into trouble (Which could have happened anyway proceeding to LHR) along the way, there are plenty of airports that could handle landing a 747 along the way. I'm not sure of the flightplan they ultimately used but flying North over Canada is a shorter distance than crossing the US. If they did that, there options would be reduced, as there are not as many 747 capable airports the further North you go into Can. (I don't think). What is a reasonable margin for reserve fuel? Is it the amount you suggested earlier of 4-5 hours of gas in the tanks when you land? Is it 2-3 hours of gas in the tanks? Maybe two days worth of gas? Is it whatever the legal minimums is? You see, anything more than the legal minimums is called "gravy." They calculated that they met the legal amount of fuel required to get to EGLL on the three engines. How much more "gravy" should have been required above that? And if gravy was required, since when did business entities become required to provide gravy?I think under abnormal conditions such as an engine out scenario the reserve should be double that as normal, since there are more factors that affect an aircrafts performance under those circumstances, ie: flying at lower altitude, rudder deflection causing extra drag etc. The margin for error or incident increases, so the safety margin must also increase! I do agree the rules should be more clearly written to avoid any ambiquity. I think part of the problem stems from when these rules were written years ago, planes did'nt have the range they do today. So it was either a trans ocean flight or a transcontinental or domestic flight Trans Ocean flights inherently gives you less options so the basic choice was go back or proceed. The choice was usually made by which was the shorter distance. Today flights cover both terrains, so there are more choices. If the goal was just to meet minimum safety requiremnts the rule would have just said the pilot could continue if it was safe to do so. Adding the term As Safe indicates he could only do this if it didn't diminish the safety margin, in this case it did.

[Guest Adverse Yawn]

Tom,Yes its a tough choice. I still agree with Kevin though. It seems that given the same data that was available at the time, the correct safe and commercial decision was to continue. If I were the Captain's boss and he chose to divert when the data said continue I would asked for an explanation and why should he should earn

[KevinAu 441]

That's some pretty preposterous stuff you're asserting about the process of fuel dumping. Firstly, the chance of the fuel igniting while being dumped is extremely small. About as big as the fuel igniting while sitting in the tank. Second, the fuel is not dumped "into" the ocean. If dumped at altitude, the fuel atomizes into the atmosphere before it ever touches anything solid. The only threat to the environment is probably the continued depletion of the ozone layer. If safety is as important as you make it out to be, then I do not understand these arguments against dumping fuel.OK! So fuel reserve should be doubled. Something concrete to work with. You can certainly go and petition The Administrator to amend 121.565 to add a requirement that the redispatch under three engines use a higher reserve requirement. Nothing wrong with that. But that is not how 121.565 is currently worded when they made the decision considering the current rules and the current situation. And even if they did change the rule, what difference does it make? Next time this kind of incident happens, somebody continues and again falls short, and the media gets ahold of the story, you can be sure that we will be right back here having the same argument. What is safe enough? 45 minutes reserve? 90 minutes reserve? 180 minutes reserve? It makes no difference. The letter of the law is what people will go by and they did it according to the letter of the law.We can argue about "as safe" until we are black and blue in lawyerland. Your assertion is that "as safe" should be as safe as the original dispatch conditions, complete with extra tanker gas, and all systems fully functioning. But that would imply that the basic laws are inadequate. Because if a flight is dispatched with exactly enough fuel to meet the fuel requirements, then it is by definition not as safe as a flight dispatched with extra fuel, since a change in the situation in the latter flight that brings it down to only just meeting the fuel requirements would make it an unsafe operation, even though it would have landed with the same amount of fuel onboard as the first flight. The implication is that the basic law is inadequate because if you padded yourself with extra, and then the extra got used until all you had was just the basic requirement, then it is unsafe. So is the basic law safe or not? If you make a requirement that people only operate under conditions as safe as the original condition, than people will always only operate under the bare minimum requirements, since outlaying any extra resources will only put them at risk of violating the law if the extra resources get used. Unless you want to open up that box of worms, they were "as safe" because the conditions under the three engine redispatch still met the basic requirements of landing with a certain required minimum amount of fuel.

[tf51d 284]

That's some pretty preposterous stuff you're asserting about the process of fuel dumping. Firstly, the chance of the fuel igniting while being dumped is extremely small. About as big as the fuel igniting while sitting in the tank. Second, the fuel is not dumped "into" the ocean. If dumped at altitude, the fuel atomizes into the atmosphere before it ever touches anything solid. The only threat to the environment is probably the continued depletion of the ozone layer. If safety is as important as you make it out to be, then I do not understand these arguments against dumping fuel.I'm not saying I believe it, but that's what the argument for not dumping was in the article!!