As an old B744 driver I say well done to the crew involved, forget about all the bullsh*t ,you kept the aeroplane flying ,no one was hurt, that is what aviation is all about WELL DONE

Not a very PC statement to make but I find myself agreeing with you. That´s why I choose very carefully who I fly with. It´s not by any means a 100% guarantee of course, but it does improve the odds by a few percentages.

After sunset usually the temperature will have dropped a little but whatever the temperature the performance calculations will have been based on that temperature.

In my experience at the stage it happened the pilot flying would or should have acted instinctively at the occurrence of the stick shake i.e. reduce the angle of attack as much as was possible at such low altitude simultaneously selecting full power, assuming any more was available.

Day or night the instrumentation and cockpit illumination is adjusted to a level to suit the conditions. They are clear and easy to read day or night for that reason.

There are no warning lights as such on the B747-400 except for the Master Warning/Caution light on the glare shield which illuminates when the level of EICAS (Engine Indicating and Crew Alerting System) warning message warrants it.

A reverser unlocked will normally be indicated by an amber 'REV' in an amber box above the relevant engine EPR (Engine Pressure Ratio) indicator and an EICAS message 'ENG REVERSER' will be displayed if a fault is detected. In the incident concerned I have no idea what the systems were doing nor which message(s) or warnings, if any, were triggered.

After rotation the handling pilot is flying by reference to instruments even having reduced the AoA I doubt looking out the window would have been much help but that is only my opinion.

Factually incorrect. For whatever reason the aircraft sensed that a reverser(s) was or was about to be deployed and retracted some of the LE devices as per design. The cause was a fault somewhere not the rather glib assertion that an individual having a bad day during the design phase made a mistake many years ago.

He is alive and well. He may or may not have been the handling pilot.

Assuming a Third World crew, as you so condescendingly refer to them, had legitimately qualified for their positions and had had the benefit of the level of thorough training many of us enjoy I am sure they would have been just as successful as us superior First World pilots.

The difference and problem is that nepotism and bribery too often influences the selection criteria and training standards are poor in far to many airlines run by bankrupt and corrupt countries.

A question - if you're at 35ft, flying by instruments, is the PNF looking out of the window for obstacles? I appreciate that anything but a straight line is going to be problematic at that altitude. Obviously the problem manifested itself when there was still runway in front, but there wouldn't have been much time to react, get the engines spooled up and gain a bit more altitude. (I know it's several seconds from idle to decent power, what is it from typical flex t/o power to TOGA?)

I very much doubt it. More likely looking in trying to work out WTF is happening.

In my experience not very much. You are often into the last 900m of runway at JNB when you rotate, with a ground speed in excess of 180kts.

If there is any derate at JNB it's usually pretty small. I'd be surprised if it took more than 5 secs to go from derate to max power.

Bit of a jump in the logic there don't you think?

You rightly praise the sufficiently experienced crew for pulling themselves out of a hole.

Then you ask how many Third-World crews might have managed the same.

I'm not sure where the third world bit comes in, unless you equate it with inexperience?

Doesn't it worry you
 

Xeque
A more rational answer to your query is yes. Yes, it is worrying for the simple reason that this appears to be another one of these things that was either completely unforseen at design stage or more probably, the likliehood of such an occurrence was deemed to be so remote as to not require any additional protection against.

If you look carefully at what happened here, there were two simultaneous and erroneous indications of thrust reverser deployment. I will leave it to the designers and mathematicians to give the odds on that happening. But happen it did (based on these "reports" so far) but according to an earlier explanation it also required the a/c to be "on ground" though air/ground sensors, so further reducing the chances of this event. So it looks like all things conspired in the worst possible sense against this crew but they have managed wonderfully to rescue a dire unforseen event.

It is a fact of aviation life that all professionals strive to do everything within their power to do things correctly and properly for every flight but that there will always be something new to catch one out. It has always amazed me how some very old aircraft types still have bulletins, both technical and operational, being issued donkeys years after all glitches should have been ironed out.(I am not talking about wear and tear here)

I could go on an tell the tale of a B737-200 where all flight and ground spoilers (was 8 or 10?) deployed inflight when the speedbrake was selected. Only flight spoilers (4 off) should have deployed and it was "impossible" by design for the ground spoilers to so do. Yet they did and at relatively low height. That was over 30 years ago but I will never forget that Captain's face during the debrief. But I won't bore you with that story now.

Not so much inexperience but training, culture, training, discipline, training, training, and training!

spurious fault
 

In several posts it has been noted that the t/rev EICAS indications were spurious. If that is in fact the case why did the l/e devices retract?

Well done to the crew however I'd like to see the report before the word spurious becomes the norm like on the Airbus

Brgds
SB03

Plainly the reversers did not deploy. They either unlocked or the system sensed they were unlocked when they weren't.

The leading edge slats did what they are designed to do when reversers are unlocked. In other words the LE salts behaved correctly for the sensed condition, actual or otherwise.

There is a prox sensor on the lock, and another at the top left of the cowl. If either is 'far' then the amber REV will come on. It is extremley unlikely that the reverser unlocked. Most probable is that the cowl closed sensor went to 'far'. I have had this happen when a flex drive sheared between the motor and the number 1 gearbox. The reverser doesn't move, but the top left corner of the cowl flexes just enough to bring on the REV indication. Unfortunately at present on a B744 this gives a signal to the inboard l/edge flaps. I expect a mod to come out to need the unlocked sensor to indicate 'far' as well.

Thanks, Swedish Steve, for that concise description of system indication. :ok:

Avman, et al:

I am just a lurker on this side of the forum.But going by your statements,the crew at Buffalo,NY was inexperienced, and had inadequate training. So does that make the US a backward Third World culture with folks who can bribe their way to a pilot's seat?
Not taking anything away from the BA crew, but it is sometimes sickening to watch my associates from the First World, strut around like those Magnificent Men in Their Flying Machines.
Going back to lurking now.
Alt3

I had a similar not so dramatic incident with on a Air China flight out of PEK in a 744 three years ago. As a pax. Plane was already accelerating pretty much, when it made an abort. Pretty hefty and impressive.
You could imagine that there was no decent info why and what. After the runway was cleared and a/c parked, we waited and I noticed mx in and out and on one of the engines. Found one of the pilots and he explained in english, that the Amber light came just after the acceleration. Great they could abort.
Of course, sensor issue, rev locked and after the usual paperwork back to runway.
Great work, but nobody except me knew really what it was. This is China. And a very new 744.
Danny

Thor,

The action taken by the crew was successful. You have the result and you can try to simulate other actions to try to prove if, or if not, the actions taken were optimal.

Given the exact same circumstances, follow exactly what the crew did. We know that it works. Who knows if leaving the gear down would be safer? What would you do? If you were unlucky enough to be in the exact same position, would you back simulation or an actual event?

Great job by the BA pilots.........enjoy the time off.

As for Danimal's account; sadly, there were no " fans " to crow loud and clear about the great job the Air China crew did!

The BA cre sure have die hard fans like wobbly and ilk.

Well done BA crew,

I find it very disturbing that we dare to judge the BA crew and their actions in avoiding a disaster from the comfort of our home having all the time in the world to micro-analyze.
They reacted according to their natural instinct increase thrust and clean up. Whether it was the most optimum reaction or not, who are we to judge?

Fact is, they saved the day with very little time on their hand. I know the feeling of going down a long runway at night on a quad with a lot of heavy metal behind you, there really is not much time to think of every possible outcome to a situation or what might be the best way to sort a problem. All you can do is, fly the plane and use airmanship.
That's what they did. That's what so many crews all over the world do every day, in every country (third world or not). The fact that we don't make the news headlines everyday just proves it.
Once again very well done BA!
My utmost respect for the crew! :D

No question this crew did a brilliant job (gear retraction notwithstanding)


No one seems to be questioning Boeings design logic here however. I understand the reasons for the auto slat retraction on landing with reverse thrust activation.


What I dont understand is why this system does not lock out above say 100 knots.


No matter what your engines are doing none of us want our slats auto retracting as we are approaching or are after rotation speed.


Seems an easy fix ?

Because you will be landing and selecting reverse above 100kts, so therefore the LE will need to retract as per the design.

Better to lock out with the fwd thrust levers in the take off range.

How long did it actually take??
 

Quick question...

At such a low altitude... stick shaker going...
Gear up is selected. How long does it actually take from Gear up select to actual gear up? :ooh:

A few points.

1. Gear up selection will increase drag for a little while, but very soon after drag will be back where it was before and then a big reduction in drag as its all stowed away, times like this you want all the 1 and 4 EDPs and demand pumps plus all eng bleeds in working order, strange fact is the operation of the L/E will be using bleed air that the demands would like very much at that time
.
2. Gear up selection will also give a little pitch down effect, may of been a good thing on said flight.
.
3. Leaving gear down in case ground contact is made may be good in some events like a G/A, leaving gear down in this event may or may not have been good, had gear of made contact again, story could have a different ending.
.
End result was very very good, well done to all.

Here we go with blow by blow analysis of what would or would not have been the best course of action before we know EXACTLY the sequence of events.

Whether they raised the gear or not I have no idea but in light of the above post if you ever watch a jumbo retract its gear it is not by any means a rapid process. It is a fact that raising the gear increases drag when the gear doors are opened during the retraction sequence and so the statement above that the aircraft would benefit from the ultimate drag reduction is fanciful if you have crashed in the meantime.

The basic facts are known, the crew flew the aircraft to a satisfactory outcome and speculation about what they should or should not have done is a waste of time until the full report is eventually published.

IIRC there's rising ground beyond the end of the runway at JNB. If you can't climb with the gear down I'd say it's better to take a temporary sink over the flat ground and get the gear up than dogmatically stick to SOP and fly level into the approaching terrain!

At JNB as you get airborne, in the dark, the end of the runway is already behind you. Typically V2 is 180kts. Ground speed is well over 200mph. With the nose rotating to 13 - 15 degrees, all you can see out the window is inky blackness. So it is very quickly onto instruments.

Simply put, you are out over the bush at about 100' doing 195kts, climbing. It is an interesting debate about the gear. The 744 had not stalled. It had a stick shake. So was close to a stall. With the gear now moving up you get a drag increase from the doors. No lift reduction. The gear does not affect the lift the wings are making. With the engines being fire walled, the drag increase is more than accounted for. The assumption in that statement is that they would have been using reduced thrust. It would be very unusual if they were using full power at JNB.

Wheels up or wheels down sinking into the veldt at 240mph is catastrophic. So the only reason not to raise the gear is the one of the doors, and the resulting drag increase. We could sit and debate endlessly whether the wheels should or should not have been left down, but what we do know is that the gear came up, and they flew it away to a safe outcome. So on some level, if not on all levels, the crew made the correct call.

Simulate gear up drag?
 

There seems to be considerable debate about whether it is better to increase drag temporarily by raising the gear, or not - maybe this issue is deserving of simulation as an answer cannot be arrived at intuitively?

Edmund

I think this discussion shows that you can't write SOPs for every conceivable occurrence and that Airmanship is thankfully still alive and well in some quarters.

I'm sure at the back of their minds was the possibility of needing to rapidly shut down an engine if it actually went into reverse (very unlikely, even at that stage, but...) and having the gear down at that point wouldn't be a great help.

The same sort of thing could be said of the BA38 double engine failure on short finals: the QRH is written assuming that there's reasonable time available for relights, not that you're going to be on the ground in 40secs...

It's a simple calculation in a performance deck if you have access to somebody who knows

In the windhsear and gpws situation greater minds have determined that there should be no change in configuraton until the warnings have stopped and you're safely climbing away, gear doors produce drag...so 99% of the above is :mad:. Some infromed comment would be good...just occasionally

...and can run the figures with 2/3 of the LEDs retracted... :eek:

There is the possibility that they might have needed to accelerate in ground effect before climbing, given that they were close enough to max AoA in the config. they found themselves in to trigger a stick shake. A few seconds thought (which is all they had) might have led to the conclusion that this would be easier/more effective with the wheels up?

I think leaving the gear down in those scenarios is more to do with possible ground contact during the recovery than with drag. If you give the terrain a glancing blow with the undercarriage rather than the engine pods, it may produce a better outcome. Keeping the wing the same section allows for a better initial ROC in the GPWS instance and a better climb rate/gradient in windshear.

But the take-off sop is positive climb, gear up. So they may have already selected gear up before the stick shaker activated, or at the least have called for it's selection. They were faced with an unusual situation and dealt with it very well.

SMOC, your solution (locking the LEDS) with the thrust levers in the forward position seems a good one.


Can anyone speculate as to why this is not done ?

Perhaps because it would require one more layer of interlocks (and associated drills) which may cause problems when you wish to retract the flaps/slats after a normal takeoff ?:rolleyes:

Sygyzy: Um, No windshear. No gpws. They had a stall warning. Out over the bush in Africa. Doing 195kts. Climbing. They selected full power.They climbed away and landed with no trauma.

I would like to think that my comments were informed. I am a 744 Captain. I have over 5000 hours on the beast. And, to date, have managed not yet kill myself or any passengers. I am more than happy to admit my view of the incident is wrong. But your erudite post has yet to convince me.

Presumably a stall warning indicates the aircraft is approaching the stall. What are the standard stall recovery actions on the BA B747?

My manuals for the B777 categorically state do not alter the aircraft flap or landing gear configuration so does the B747 uses different procedures?

My immediate concern is how the false reverse signal was generated on two of the engines. If this can be identified accurately and resolved then hopefully it renders the speculation about gear doors at 200 feet redundant. I would say RFI is a strong contender.

The stick shake occurred at 12.5 feet radio.

L337

Not too much bush at Joburg mate. But, as a matter of interest, what role did the runway they took off from play in the positive outcome of the event? The ends of the 21's appear to be more forgiving than those of the 03's.

BTW, I'm no pilot, only a humble chemist.

It was a departure off the 03s.

M. Mouse - what the B777 manual says is irrelevant. The B744 has a procedure for stalls and a procedure for double engine failure, but not one fir both events simultaneously on departure. It would appear in this case the crew decided that cleaning up in case of the need to shut down one or more engines with deployed reversers was the priority over the stick shake and that demonstrably worked. The aircraft will fly just fine on the threshold of the stick shaker. It won't fly with two engines out and the gear down. Think Concorde.

Makes a lot of sense. It probably wouldn't have taken much of a reduction in pitch attitude for the aircraft to make ground contact and I expect that would have been beyond the end of the paved surface... :ouch:

They seem to have ended up in a similar situation to the EK flight out of MEL, i.e. passing the end of the runway in an aircraft almost too heavy to fly in its current configuration, only for completely different reasons. At that point, SOPs get put to one side and as our colleagues from the USA would say, the only option left is to "fly the airplane". Well done.

This is a direct quote from the Boeing 744 QRH.

To have Engines 2 and 3 REV "Amber" (unlocked) warning lights, then have the inboard and mid LE slats retract, and then have a stall warning at rotate is beyond the scope of the QRH. This scenario is not something that forms part of any check or training in the simulator. The situation required them to rely on their own judgement and experience. There is no definitive flight crew procedure for the combination of events they were presented with.

They had no time to diagnose, they had no time trouble shoot, they were straight into "mitigate".

As we know they elected to raise the gear. They also landed safely, and nobody got hurt.