As stated. 747 on 3 engines has thrust redundancy, 777 on one engined hasn't!

BEagle:

Yesterday I did a two engine go-around in the simulator. The 747-400 Simulator.
We began the approach at Max Landing Weight. 285,000kg.

Once TOGA was pressed, ie the Go-around commenced, we had a rate of climb in excess of 1200' per minute.
BEagle I am not too sure what you mean by "no thrust redundancy" we had plenty enough. More than that we then went on to do a circuit and land on one engine. Just for the fun of it.

I cannot say strongly enough to those of you that have flown older generation wide body triples, and the Classic. The -400 has huge amounts of power. As in Huuuuuge. The levels of redundancy in the -400 are immense. Just to give you an idea of power. At Gross weight out of Singapore. So around 395,000kg we still use reduced power for the takeoff. From memory 2 engine drift down at 340,000kg is around 20,000'.

Power we have lots of.

Firstly, of course you are correct. However, the risk management is the essence. The - 400 spends lots of time over some very bleak and barren bits of the world. It is often far far safer to continue on three, than to land into a poorly lit, badly maintained airport in the third world. Or 40kts in ice, and snow in Siberia. On metric altitudes trying to remember to use QFE. All on three engines. Clearly it is barking to land.

Then again if all your en-route alternates are CAVOK. The route planned gives you to nice long runways to divert to, if so needed. You have enough fuel. You are happy with the state of the aeroplane. Why not continue?

Too many people here seem to think that the -400 on three is about to crash. On two, death will be the certain.
Boeing built an amazing aeroplane. It is much, much more capable than you think.

BEagle wrote..

But, (un)fortunately the pax don't get a say in the matter! That's the job of the crew (in consultation with engineering, operations and if necessary management pilots) who have undergone extensive training & checking along with a large dose of experience.

Heaven forbid the day we have to consult with the passengers during a 'problem' to see if they "are prepared to accept the same level of managed risk." We are NOT running a democracy up there. That's why they pay me the salary they do and trust me to make those difficult decisions.

A little knowledge is a very dangerous thing.

Idol

(And as L337 'proved' the thing will fly on one engine quite happily if you're light enough. Two engines is no big deal and three is a non-event (imho))

Very well put. I have refrained from involving in this thread because following the incident, I was heavily committed to explaining the circumstances in the original thread. It ran to about 50 pages! I got totally fed up explaining fully the same things over and over again to have some new armchair exert who once flew a flight sim interjecting for all he was worth about something he knew nothing about! So you start again, and have some other poster bring up the same points!

I put this to everybody: the pilots who actually fly the thing and have no intention whatsoever of hazarding their own lives and having their kids brought up without one parent are only too happy with the flight continuation policy! So am I, and even under extreme management pressure (which is not applied at all), if I felt the policy was not sound, I would not carry it out for anybody. But those very pilots who have been flying the aeroplane for umpteen years (like myself) fully agree with the policy because on such a 4 engined aeroplane, it is the safer option to continue. It is also far more environmentally friendly. The FAA sitting in its offices, for I suspect political reasons, may not agree with this policy. I can only point you to the fact that I suspect for political reasons, they have determined that it is perfectly acceptable to expose passengers on ETOPs flight across the Pacific to placing their survival hopes on one single engine for 3 hours (and more). I say one is acceptable, one is not. I know which I would be far happier on. So if anybody thinks the FAA is acting completely altuistically, I would say they are not examining the pressures on the FAA regarding B777 v B747 and B777 v A340.

This is another old chestnut. Whoever wrote the above, please take a globe, find LAX, find LHR, get a bit of wool or string and lay it on the shortest distance between the 2. How much 'ocean' is there?

Overstress

Off to lie in a darkened room

Using some of the logic we see on this thread, I wonder how much the FAA will fine Evergreen for this incident ??

N481EV

The aircraft lost an engine over the UK, yet the pilot decided to divert back to Ramstein in Germany instead of somewhere closer. This was cut short as the aircraft could not maintain altitude and had to divert in to LHR. (Seems to me that the principle is the same as that exercised by BA). Another 'fineable' offence perhaps is the pilot chose to fly to an airport and in airspace for which he had no charts :ooh: Not to mention taking his (unairworthy in the view of some posters here) aircraft over central London with a dangerous cargo onboard.

I suppose the saving grace is that there were no paying passengers on board to take a vote on the safety issues :p

The great pity is that even in this Forum, it is impossible for pilots to have a serious discussion because of all the non-experts sticking their noses in with desires to 'take votes on board'. One despairs. Maybe a Forum Section where it is continually warned ONLY PILOTS TO POST!

Well, it's an open forum and everyone is entitled to their opinion - it is up to the reader to make a judgement as to the validity of each post.

There is a diversion (!?!) from the real issue here. I have no problem with the performance capabilities of the 744 on 3 engines. I have never flown a 744 but know it to be a very capable machine - as you chaps that do fly it tell us it is. I am familiar with the LAX - LHR routeings though and have no major problem with an extended 3 engine flight in this area. No major problem that is... I am not sure that I would have taken the same course of action but then I have rather a yellow streak!

But I think that some BA contributions avoid the main issue here. That is that, after all this superb BA planning and airmanship to get the kite home, a fuel situation was allowed to develop. There was an actual or perceived fuel shortage that concerned or confused the crew to such a degree that an emergency (was it a PAN or a MAYDAY I don't know) had to be declared and the A/C made an emergency diversion to MAN.

Now, I have no doubt that the crew did a good job under the circumstances, but why is it that some of you chaps will argue until the cows come home that this was a superb operation by the whole team. Christ, if this was a superb operation I would hate to be on one that went wrong!

Naturally, you guys can shoot me down as another armchair expert who knows nothing about the 744. But as someone so beautifully remarked earlier - airmanship is not type specific...

BS

bullshot

The fuel situation, and the reasons for the 'mayday' were covered in great detail on the previous thread, including diagrams of the fuel system. I suggest that you go to those threads and read it, rather than us have to repeat it here.

Airclues

Airclues.

Great condescending reply!

I could add that a diagram of the 744 fuel system is totally irrelevent to my point but I guess it would be lost on you.

Some of you guys have attitudes so fixed in concrete that it's worrying.

BS

For the hundredth time - a 'fuel situation' did not develop. The fuel was exactly as it should have been, it was a misunderstanding of the standpipe level and fuel pump pressures that led to the crew to believe, incorrectly, that some of their fuel was unusable. Having reached that incorrect conclusion they did no give themselves the luxury of time to pontificate at lenght that you have Bullshot. Given the circumstances they chose the safest option at that time which was to declare a Mayday and head straight for Manchester. If I believed I had that little fuel I would do the same. The only place this operation went wrong was the crews mistaken belief that they suddenly had 2 tonnes less fuel available than they thought.

What I actually wrote was "But after the loss of an engine on take-off, it has no further 'thrust redundancy' for a protracted flight to a destination some 4700 miles away."

Note that last part - a protracted flight to a destination some 4700 miles away.

Of course you can fly 2-e go-arounds in the event of loss of thrust of another engine and subsequent diversion. But no matter how much faith you have in the management's decision making back in London, the decision to cross the Atlantic in such a situation, irrespective of system redundancy, is not the same as a decision to divert to the East Coast in slow time, and transferring the passengers to an onward flight.

As for passnegers considering risk management strategies, I'm not suggesting for one moment that there should be some form of onboard consultation! That's plain daft.

But if airline A gets a perceived reputation for pressing on for 5000 miles after an engine failure on take-off, whilst airline B declares that they aren't prepared to take such a risk, slight though some may consider it to be, that may influence the opinion of the passengers.

One of the hazards of free speech and the desire to help wanabees / self improvers in an open forum is that you often have to suffer some extreme and/or inaccurate views. These can and must be countered with strong moderation and accurate, professional responses; well done Danny et al, maintain the strong moderating stance.
We need to put professionalism back into Pprune. This forum is a valuable industry resource which has to endure the ravages of media – we have to educate them as much as ourselves, and as well, provide a well balanced public view. This requires professionals to lead by example with disciplined thought and communication – aspects of the day job, which hopefully the less informed or ill disciplined observer can learn from. After all, it is public perception that ultimately decides the fate of our industry, and if we do grossly mismanage our flights it is the members of the public that will form the jury.
As for the incident; the crew judged the situation on the information (including rules and procedures) available to them at that time.
Many posters are attempting to judge the incident, but not in the same time scale, nor with the same facts as the crew had. This behaviour is typically influenced by hindsight bias. Similarly the apportioning of ‘error’, a form of blame, can only be made after the incident has occurred. No crew sets out to deliberately make an error; yet in hindsight, human nature seeks error or blame as a means of achieving improvement.
The industry must celebrate the successes, irrespective of the apparent facts and circumstances. The crew made a decision, continually rechecked and evaluated options as the flight progressed and, when required, took another appropriate decision that maintained the required level of safety. These are the issues that should be highlighted; we require rational and well considered discussion to see how best these can be translated into ‘experience’ that all of us can retain and use if and when appropriate.
__________________
Unless specifically authorized everything else is forbidden.

bullshot

I fail to see how my post can be seen as condescending. Frustrated yes, condescending no.

On the previous two threads several 744 pilots went to great lengths and spent a great deal of time explaining exactly why the crew mistakenly thought that some of the fuel was unusable. The CAA issued a bulletin to all 744 operators pointing out the problems with fuel balancing with an inboard failure. We all learned valuable lessons from this incident. Nothing was covered up, and the errors were freely discussed on PPRuNe. However, because you cannot be bothered to trawl back through the previous threads, you want us to write it all out again. Sorry but the world has moved on, and I for one have better things to do with my time. My post simply suggested that you have a look at the previous threads and you will get all the answers that you require. What is condescending about that?

Airclues

I can understand this point of view if the position is that you have to make a once-and-for-all decision whether to return to origin, to divert to an alternate, or to continue to destination. But that is not the situation that this BA crew was in. They could continue, and still have the luxury of being able to change their minds if anything else went wrong later and then to take one of a significant number of alternative options.

Indeed, as it happens, they thought later on - much later on, when the already on other side of the Atlantic, IIRC - that something else had gone wrong, and so they availed themselves of one of those other options at that time.

[Sorry, pilots, for butting in to this, but the logical fallacy of the premise behind this argument just jumped out at me.]

I digress, sorry, but,

BEagle wrote..

You said it....

...here..

Or did you mean something else entirely? :rolleyes:

Idol

BEagle. I've corrected you before and I've mentioned this time and again on this and the other threads. The 'Atlantic' and the 'East Coast' are not relevant on the LAX LHR route. Canada and Greenland, followed by Iceland. You are misleading many on here with this kind of stuff. Why would you want to cross the USA to the 'East Coast'?? Where on the route is the great stretch of 'Atlantic'??

All: please look at a globe.

Idol, I was referring to the influence on the future choice of passengers as my last post made clear. Not to some in flight debate conducted at the time.

Overstress, I'm quite familiar with the routes in question, thank you. And yes, the great circle route from SFO to LHR crosses the Atlantic a long way north, via Hudson bay and Greenland (although the winds of the day and ATC restrictions will modify the theoretical great circle route, of course). And by the time various London managers had been consulted, there was probably insufficient fuel to plan a more southerly route, perhaps via St Johns, as that would have been about 400 miles further - although much closer to suitable en-route alternates.

SFO to East US, transfer pax to another flight. That's what I conclude would have been the best overall compromise.

Are you really au fait with long range ops BEagle? The moment they left the stand at LAX there was insufficient fuel to plan a more southerly route via St Johns or indeed anywhere else. On the subject of which, why is St Johns considered more suitable than Keflavik? St Johns and Halifax are frequently in the mire at the time an LAX flight would pass them whilst Keflavik is wide open. If you are concerned about passenger inconvenience then you are misguided in your suggestion that the east coast of the USA would be more suitable as by the time the LAX flight got there all the BA flights would have left for London. Furthermore any such flight would still have incurred the wrath of the FAA, who are objecting to any 3 engined continuation policy.

There is some seriously muddled thinking in some of these posts with a hodge podge of phoney technical objections and confused concerns for passenger convenience, few of which bear and close scrutiny.

Sorry - I was referring to St Johns as a coastal fix rather than an en-route alternate!

I am familiar with the routes, not with ba SOPs. Some of you find difficulty with plain English, I fear.

Well I thought you would be as I know the military type you flew - so why confuse the MS sim types on here with talk of 'ocean crossings' ?

But your point that you're not familiar with BA SOPs - they are very different from your GASOs. If your 'operating authority' prefers you to bring the a/c home, and it's within the rules, you'd better have a good reason not to.

For me the real point is why the crew felt it necessary to declare a mayday and did this indicate that safety was compromised.

In trying to reach destination the crew, for whatever reason, considered safety to have been so compromised, that they decided it prudent to declare an emergency in order to effect a safe landing. I am entirely with the crew on this one and have never criticised them in any way.

Now though, some of you guys argue that actually a mayday wasn't necessary - they had all the fuel they needed and that the flight was as safe as any other! You want us to investigate the entire fuel system of the 744 to make us agree with you. Well, the crew certainly didn't think so at the time otherwise they might well have done things differently. Perhaps, for example, like landing at GLA or some other suitable airfield without the need for a mayday.

No chaps - it's you I have a problem with (you know who you are), not the crew of this flight. Your aggressive defense of a system that, on this occasion, clearly failed, simply encourages others to ask questions that you can only answer by resorting to feigned exasperation or ridicule. 'How dare someone has the impudence to question the safety of a BA flight!'

On balance, I'm with the FAA on this one.

BS

Sorry but theres some serious contradictions in that post Bullshot. You say you are completely with the crew and do not criticise them but imply that there is something wrong with BAs handling of the operation, yet that is completely at odds with the reality of the situation. The handling of the flight and all the associated flight planning was spot on right up until top of descent at which point a misunderstanding by the crew led them to declare an unnecessary mayday. If you want to start levelling criticism then I'm sorry to have to tell you this but the error made on the day was that of the crew, not the people on the ground. The fact that you think the crew should have landed at GLA shows that you simply haven't grasped what caused the mayday to be declared. AT NO STAGE PRIOR TO TOP OF DESCENT DID IT APPEAR THE CREW WOULD HAVE INSUFFICIENT FUEL TO MAKE THEIR CHOSEN DESTINATION WITH RESERVE FUEL INTACT. Is that clear enough for you?

It goes in circles, doesn't it. Head, wall, banging, against,....say the same thing again and again to the same people, and some other poster comes up with the same thing that has been rebutted 3 pages ago.

Folks, the flight continuation policy is correct (for a 747-400). It works well, and is perfectly safe. The events at the end of a flight were an automatic emergency alert, not an emergency call.....you have to understand the rules in aviation! Those events at the end were a separate issue, not a direct consequence of the original problem. Argue until the cows come home, the policy is correct, the CAA apparently agrees, the FAA has got other drums to bang as well and is definitely not to be trusted. The policy still applies in BA and is supported by the very people who follow it. Those people have the option to not follow it, but they do willingly! Does that not tell you something?

bullshot

Whether or not you agree with the continuation policy, the fuel on board was initially enough to make LHR. However, due to en-route circumstances the crew elected to divert. The logical choice of alternate was one with two runways, ie Manchester. The fuel remaining at MAN was predicted to be well above reserves. However, on final approach the crew thought that some of their fuel might be unuseable, and therefore in compliance with JAR rules, they declared an 'mayday'. The reasons for the confusion were explained at length in the previous thread. In aviation we are always learning, and this incident taught us all a great deal about fuel management (how many times have you seen an inboard engine failed on the simulator?). I apologise if you see this as condescending, it is not intended to be.

BEagle

Sorry to disappoint you but the forward bookings for the LHR-LAx route are well up for 2006 (PM me and I'll send you the figures). It would seem that the passengers are voting with their feet.

Airclues

"Argue until the cows come home, the policy is correct, the CAA apparently agrees, the FAA has got other drums to bang as well and is definitely not to be trusted. The policy still applies in BA and is supported by the very people who follow it"

This would appear to bear out your comment, bullshot.

Why is the 'apparent agreement' of the CAA any more to be accepted than the view of the FAA which, it is being alleged, is 'definitely not to be trusted'?

The fact that there has been such a difference in views means that this is far from a cut and dried issue.

The redundancy of 747-400 systems is totally irrelevant to this issue; this was a 4-engined aeroplane which lost 25% of its available thrust on take-off. The issue at stake is whether, as a general concept, it is an acceptably low degree of risk to plan to fly the remaininder of the flight to the original destination with fare paying passengers on board over such a lengthy sector.

BEagle
Having read this thead and the previous, the answer is: Yes it is.
Surely what it comes down to is that there is no single answer as to what to do in the circumstances. What hacks me off is that there is always someone on this board who thinks that the crew did the wrong thing. Aviation isn't like that and that's what makes it interesting.

Have YOU ever heard the word "HOMITIS" and its dreadfull consequences?
Think over it infallible aces!
Fly safe DOVE

No, never heard the word HOMITIS, not sure it's even a word in this language. Perhaps you mean something like the phrase 'press-on-itis' which you would understand did not apply in this case if you had bothered to read the threads fully instead of just repeating previous points.

The FAA have a mandate to promote the commercial interests of the American aviation industry, hence their lobbying for increasing ETOPS times whilst minimising the advantage of quads. Even the manufactureres don't trust the FAA. If you think the FAA are acting with complete impartiality in this matter then you are rather naive.

It normally loses 25% of its thrust at 1000ft when we go back to climb power or less. Are you familiar with the term Max Continous Thrust?

Goodness me, why is it so difficult for you to understand? You make it sound like they were off to a remote desert island with nothing but ocean on the way. The crew had the option to turn it into a short a sector at any time. It was unnecessary to do so until the reached the far side of the atlantic.

'HOMITIS'? Well, they didn't make it home! (It wasn't due to being on 3 engines). One aspect is that there were numerous enroute alternates. After departure the crew were not commited in making LHR on 3 engines. This was not an unsafe or illegal flight.

Yet again you don't take the trouble to read things properly....

I wrote "25% of its available thrust". So the question of MCT on 4 is irrelevant in this context.

One hopes that you take the trouble to read your aircraft manuals rather more carefully.

Anyway, irrespective of airline, type of 4-engined aeroplane or particular incident, the question remains whether it is should be considered sufficiently safe to continue for 5000 miles after the loss of an engine on take-off, or whether regulation should be applied to limit the level of such risk to a lower level. For example, perhaps 'the flight may continue provided that the aeroplane shall remain within tbd minutes flight time of a suitable alternate aerodrome for the remainder of the flight' for circumstances such as the reported incident.

Now discuss tbd. I open with 60....

Incidentally, I agree that the incident in question was neither unsafe nor illegal. I contend that it was, however, imprudent.

Funnily enough, I had a quick and very rough look at this last night. Now, I know that this shows a Great Circle route, which was probably not quite the exact route, I know that the scale is small, and I know that the site may not be wholly accurate - but this image suggested that they might never have been much more than 60 minutes away from a diversion airfield, if at all.

Source: the Great Circle mapper

That mapper is a trifle optimistic if you aren't careful!

I used it to display 60 min @ 480 G/S from 744-capable aerodromes (even considering Goose and Narsasuaq). Getting to the East Coast as far north as Montreal/Halifax was no problem, but for the great circle track from LAX-LHR there are some considerable gaps with a 60 min-from-suitable-alternate limit.

Thus LAX to Montreal would be do-able with such a 60 min requirement, for example. And I think that perhaps that would be a reasonable, sensible compromise.

I know what you wrote BEagle. The point I am trying to emphasise is that losing 25% of the available thrust on a 744 is virtually irrelevant. Its a meaningless statistic. The aircraft regularly takes off with max derate which is close to 75% of max thrust. With three engines it will climb to around FL310 at max weight. The aircraft can take off at 380T from an upsloping runway at 5000ft elevation and ISA +18. It has so much thrust that losing an engine is almost an insignificance bar the statistically highly improbable chance of a second unrelated failure (has anyone ever had one of these?).

Looking at that great circle map it would appear the aircraft can do the route within 60 minutes of an alternate anyway. Montreal is too far south from the actual route but if the aircraft crosses the US/Canada border at Winnipeg then there is Edmonton, Churchill and Iqualuit en route. The only time things might get tight is between Iqualuit and Sondestrom but that is no different to crossing the pond at a more southerly latitude where there'll be a crunch between St Johns and Sondestrom. Once within 60 minutes of Sondrestrom there's good coverage via Keflavik then Prestwick. I would also suggest that 60 minutes is far too conservative for an aircraft certified to fly indefinitely on three engines. Its still got 4 hydraulic systems, three generators and three engines, which is a damn site more than a 777 on one engine. Whilst the ETOPs kit might have a statistical probability of failure of one engine perhaps an order of magnitude smaller than the non-ETOPs engines, the probability of two independent failures on a 744 would be at least an order of magnitude smaller still. We allow ETOPS aircraft to fly 206 minutes from a suitable alternate but wish to restrict the 744 to 60 minutes when the chances of a double failure reducing its capability below that of a 777 on one are much smaller?

Not sure that Iqaluit or Kangerlussuaq in the middle of a winter night on 2 engines would be a nice place to be.....

However, perhaps the main benefit of this thread is the scope for professional debate concerning an acceptable level of risk.

Or on 1 engine for any of the ETOPS twins !

BEagle, so you think 60 minutes from an alternate should apply to a 4 engined aircraft with 1 shut down .............I suppose you think that 180 minutes on a 2 engine aircraft with 1 shut down is also prudent??

ETOPS considerations are, as has been stated previously, not germane to this discussion.

BEagle

...I agree that the incident in question was neither unsafe nor illegal...

A somewhat different view to the one you posted a year or so ago!

...To my mind they got away with it by the skin of their teeth...

...'halfway around the world' on 3 engines and a very tight fuel state anticipated on arrival? Many see that as just too chancy - I certainly do...

Good to see reason taking over from rant! ;)

Best regards

Bellerophon

Would they have been instructed and proceeded towards the destination (admitted that there were a spare engine and a technical staff to replace it) if they were performing the LHR-LAX sector?
This is what I mean with "HOMITIS": a dangerous temptation to go back home at any cost.
Please fly safe!
DOVES