BA056 JNB-LHR Incident.
 

I have heard different rumours (thats what this forum is about) that the
BA056 11.5.2009 returned to Jo'burg shortly after take off due to 'multiple' engine failure.

Can anyone in the know with any real facts give a more accurate account to confirm or deny this incident.

WTDWL.

The latest report
 

Incident: British Airways B744 at Johannesburg on May 11th 2009, two thrust reversers indicated open in flight

By Simon Hradecky, created Tuesday, May 12th 2009 19:05Z, last updated Tuesday, May 12th 2009 19:07Z

It's bigger than that - they nearly bought the farm:

From Av Com

by Romeo E.T. » Wed May 13, 2009 6:31 pm I have just heard some further info..........SCARY STUFF

from some of our technical "boffins" in the office today....results of the DFDR, crew interviews etc.

1)The B747 was very heavy and on rotate one of the engines flamed out, and another "rolled" back to idle RPM.....now on 2 engines only.
2)the thrust reverser light for 2 engines came on, and as per the design features of the B747-436, the leading edge devices retracted.....this is an auto response to prevent F.O.D. to the leading edge devices during reverse thrust operations..... thus even more loss of lift at a very critical phase of flight.
3)thru fast actions the captain was able to restore thrust to the engine that had "rolled back to idle".....but only after leveling off...or even descending doen to 35ft...35ft http://www.avcom.co.za/phpBB3/images...s/icon_eek.gif http://www.avcom.co.za/phpBB3/images...s/icon_eek.gif http://www.avcom.co.za/phpBB3/images...s/icon_eek.gif http://www.avcom.co.za/phpBB3/images...s/icon_eek.gif
4)the aircraft slowly accelerated to climb speed with the partially extended leading edge devices and only on 3 engines.
5)fuel dumping took 2hours
6)after landing the crew refused to take the same aircraft out again...and they "paxed" back last night
7)SACAA has impounded the aircraft at ORTIA where the DFDR has been downloaded to annalize the incident

Very scary stuff, sounds like an appalling situation handled with some excellent awareness and fast smart thinking. :D

I'm not sure about the thrust loss, that certainly hasnt been mentioned in BAs release of DFDR data.

fly around on 2 engines to dump fuel for 2 hours?
Sounds both insane and untrue. The rate of Jettison in the -400 with all pumps operating is 105000 kg/hr, so explain me how much fuel they exactly carried.

Engines 2 + 3 gave spurious thrust reverser unlocked indications at rotate leading to an automatic slat retraction with associated loss of lift.

Crew handled the amber thrust reverse warning with full thrust and gear retraction with onset of stick shaker.

Aircraft flown away and returned to JNB after dumping fuel.

Excellent handling of the situation by the crew who contained an extremely serious incident.

As has been mentioned before a Lufthansa aircraft which tried to get airborne from NBO didn't make it when the LE Slats weren't deployed so it shows the quick thinking of those involved.

The quoted piece above comes from AvCom topic - emergency in JHB now?

The 'authoritative' postings from people who are clearly clueless would suggest it is somebody trying to impress that he has inside knowledge when in reality he hasn't. Gems such as 'Thrust reverser warning light' (no such thing on a B744) with another idiot explaining that a B744 can only dump fuel from the centre tank (it can dump fuel from all tanks).

I do also know the pilots didn't 'refuse to fly it back'.

I am confused, surely the LE devices would extend again as soon as the craft got airborne.

From another thread...
Not questioning the integrity of the reports, just asking the question that's all. :ok:

M Mouse,

Sorry but my post was written entirely by me. Not by the source you claim. I have the full details of the incident. There was no un-commanded thrust reduction or engine shut down but the loss of the inboard and mid LE slats was enough to cause the stick shaker at 12 feet and a level off at about 40 feet.

Extremely scary stuff in a heavy 744 out of JNB.

Still, very well handled by the crew involved.

Don't think he means you Wobble.

Zulu01? :suspect:

Zulu01 I have nerer read such rubbish........clearly you have no idea of the interlocks in place to prevent leading edge devices retracting when not selected to so do!! !!! I assume on the take off roll the reverse thrust levers were not pulled, flapes not in landing range etc!!! Pure speculation and fantacy on your behalf!!!

Thats the bit thats correct. The reverse amber did appear and the inboard and midspan LE slats did retract. Looks like another interlock is needed!

What didnt appear to happen was thrust loss.

No I was not referring to you Wobble but the post by Zulu01 lifted from the AVcom website.

I have since learned that the statement ....."rolled back to idle".....but only after leveling off...or even descending doen(sic) to 35ft...35f'' is complete nonsense.

The leading edge slats DID retract at the same time as the reverser unlocked EICAS warning occurred.

It was a very unpleasant incident but was not as dramatic as the factually inaccurate posting from AVcom implies and was well handled by the crew.

Typically BA B747-400's take off from JNB at about 354 tonnes (ZFW about 232t + about 122tonnes fuel) for the 10:30 flight to LHR. This at about 15-20 deg C OAT and calm wind will require about 1.68-1.70 EPR from the engines, which is not short of full thrust.

Max EPR with packs off at that density altitude is about 1.74, ie the take off is pretty limiting, and frequently the EGT's will be about 740deg C (vs 785 max).

In those conditions, there is NO WAY that a Flap 20 take off will result in a successful conclusion with 2 engines not delivering thrust (with or without leading edge devices as expected).

There is a lot of bullsh1t here. As I understand it, there were spurious reverser EICAS messages, at the same time there were leading edge flap anomalies; but the engines still produced commanded thrust. What little excess thrust remained was applied, the gear retracted, and after at about 160'agl the leading edge devices re-deployed to the correct position.

Prior to that, stick shake activations had occurred at about 12'agl.

Well seeing as its now in the public domain!
Wobble2plank has it on the money!
It was not a reverser unlock! and on the subsequent landing it all did 'what it says on the tin'!
Engines 2 and 3 REV Amber (cowl position) within approx 15 secs of each other during the roll. As the aircraft was still on the ground this resulted in a command to the FCU's to retract the L/E flaps Group A. The reverser commands to the FCU's operate in pairs 1&4 2&3
The L/E flaps probably extended again as the a/c became airborne.:8

Sounds like Wobble and Gas have many facts.

From memory, the LH at NBO had all L/E stowed, sad day for them.

Would like to know if subject aircraft had any/much history of REV ind problems with its engines ???
.
ASN Aircraft accident Boeing 747-130 D-ABYB Nairobi-Jomo Kenyatta International Airport (NBO)
.

Wobble2plank and gas path...you 2 must be closer to the source than what I am.

as I mentioned on the Avcom website, I was on technical refresher today...course presenters are ex SAA B742/3 flight engineers, and being a BA franchise airline, we do get a lot of info handed down within the company....although "second-hand".

When our technical staff and our FSO relayed the sequence of events including the loss of thrust on initally 2 then restored to only one eng out, I believed their version of the story....

seems I may be wrong on those accusations, but it does still sound like the "reverser-unlock" and subsequent retraction of LE's close to or during rotate and the stick shaker activation still makes it a very scary event, and total "hats off/respect" to the crew for getting it safely out of that situation and to an uneventfull return to land.

M Mouse,

Sorry about that then, I must read more carefully!

:}

Thread drift here but the LH incident was/is totally unrelated to what happened to the 56.
Now a bit rusty here but.....
In that case, the engines in those days were very 'strapped' for power especially at a place like NBO and bleeds off takeoff was reqd.
The F/E had selected the pylon valves (bleeds) closed after start and at the time there were no warning lights on the front P3 panel for L/E position/disagree. (amber and green). The trailing edges deployed, albeit slowly as the EDP's were producing pressure, but without the pneumatics the L/E flaps all remained stowed.
That indication light mod. on the P3 panel came about a result of that accident.

@Turin
THX buddy for yr post, had my description only in german. U R right
Auto LE retraction is controlled by switches in the thrustlever assembly and at least 1+4 or 2+3 must be physically activated by moving the levers in direction REVERSE > 6 degrees

Strange post I guess ...:ouch:

Quick update:

The stick shaker kicked in at 12 feet and due to the quick reaction of the crew advancing the throttles and getting the gear up 'sharpish' the stick shaker stopped at 40', no level off as mentioned in my previous post.

As the aircraft accelerated the LE slats redeployed at about 160'.

Nicely handled!

Will somebody please explain what happened in terms for those not clued up on the jargon?

On rotate out of Johannesburg the aircraft systems gave a spurious warning that the thrust reverser doors (Used on landing to assist in braking the aircraft) on engines 2 + 3 were unlocked (possibly open or deployed leading to the engine thrust being deployed forward not rearward).

A potentially dangerous situation as a thrust reverser deployment in flight, especially at low speed/low level can cause a disastrous departure from controlled flight! The system has three interlocks which should prevent actual deployment in flight.

The crew could not know what that actual deployment of the thrust reverser doors was, however an actual deployment would most certainly be felt by the flying pilot!

As a damage security system the 744 automatically retracts the mid and inboard leading edge slats to prevent damage to the slats from the thrust of the engine now coming forward. As JNB is a high airfield in hot conditions with a heavy aircraft these lift enhancing devices on the leading edge are vital, all take off and climb out speeds would be calculated using LE slats deployed. Loss of those, without quick intervention could lead to a stall.

The aircraft stick shaker is there to warn the crew of impending approach toward the stall. Thus, at the onset of stick shaker the crew selected full Take Off/ Go Around (TOGA) power, brought the landing gear up to reduce drag and flew the aircraft away from a potentially dangerous situation. Normal take offs are conducted at a 'flexible' power dependant on the conditions of the day to save on engine wear.

Excellently handled and I think I can see the next 6 monthly simulator check scenario now. :eek:

I can see an engineering solution coming out too, probably in the form of some wiring changes and an extra couple of relays!:8

Potentially this would affect all 744 operators as the A/F systems are all the same it's just the T/R modus operandi that differs!

Not wanting to take anything away from the crew, but we are taught to keep the gear down in a near-stall close to the ground situation, until clear of terrain and out of stall airspeed. This is to prevent extra drag from gear door extension in a critical phase of flight and also if ground contact becomes unavoidable, it should happen with the gear down rather than in the middle of a retraction sequence.
Your thoughts?

Certainly on the aircraft I fly the gear should not be moved during stall recovery because of the increased drag during gear retraction. Can you confirm that is not the case with the B747?

I wonder it got airborne at all with that asymetric lift due to LE devices on one side retracted.The AA DC-10 crash at ORD comes to my mind.
I would have thought of a severe amount of roll to be encountered.
If the crew was able to recover that----hell of a job:ok:

I think the slat retraction would be symmetrical.

M.Mouse - it's not a published procedure on the 744 to raise the gear in a stall situation but I'm sure more detail will be available through the usual channels shortly.

CptRegionalJet

It was the LE slats on both sides that retracted due to 2+3 being both inboard engines. As you say though it could have been interesting if it had only been one reverser! [edit] I seem to remember that the system would retract both LE slats symmetrically irrespective of which engine was causing the problem to prevent asymmetric wing loading.

As to the SOP for retracting the gear I have to come clean and say I don't know as I don't currently fly the 744. However I would suggest that the drag caused during retraction could possibly even be less than when the gear is fully deployed judging by the number of wheels dangling down and their retraction sequence. At the time the desire to get the gear up and hence drag down to cancel the stick shaker would probably have been foremost. Especially if there was no suitable terrain below anyway.

Best to ask someone current on the aircraft.

744 SOP is to leave the gear down in any situation where a positive rate of climb is not being achieved, (for example a Windshear Go-around). Only when a positive ROC is achieved do you select Gear Up.

Hats off guys:D

That could have been horrendous from any airfield but out of there twice as bad!

wobble2plank,

The drag would not be less during retraction because, if you select gear up, the landing gear bay doors have to open in order to allow for gear retraction, trust me those doors are massive, add that to the landing gear itself and it would cause way too much drag, so the last think you want to do in a situation near the stall or multiple engine malfunction on take off is to retract the gear...especially in JNB.

Bokkie449

So there we have it Wobble has some accurate information but cannot leave it at that and proceeds to explain incorrectly the rest of the event.

Why cannot people just post what they KNOW to be factual?

So what would be BA's statement on said incident? If there's any.

All the actions carried out by the crew proved to be effective, regardless of what any current SOP states. That is a fact.

I'm asking this as a PPL and therefore as a non-B744 driver, but would the fact that the takeoff was after sunset have made it better or worse for the crew.

Obviously it was slightly less "hot" (but still high), but is it easier to run through options available only 12 - 40 ft off the ground during the day, or at night.

Are the instruments/warning lights clearer? Does it help seeing the ground in daylight, or is it all pretty moot in the timeframe they had to react?

Without going into the detail, and without wanting to denigrate the (possible) actions of the crew in any way, isn't that the equivalent of saying anything that you do that doesn't result in a crash is effective?

The question should be whether they did actually retract the gear then, and if they did, was it the optimal reaction? It's a serious enough incident to warrant speculation, but we'll only know when the facts come to light.

TN

Doesn't it worry you?
 

All you professional guys out there - doesn't a story like this worry the hell, out of you (and the pax sitting behind you)?
You've done all the calculations, correctly set the aircraft up ready for takeoff according to weight, altitude, weather conditions etc. Are you not completely in control during the critical 2-3 minutes that follow?
When I push the throttle forward in my C152 and commit to takeoff I expect to be in total control for every aspect of the flight thereafter including an EFTO.
This story suggests that a computer (a machine of questionable integrity programmed by a nerd who might or might not have been having a bad day) decides that a major mechanical malfunction has taken place (when it hadn't) then retracts essential lift devices at the very moment they are needed most and all of this happens between 12 and 40 feet above ground. Whatever happened to PIC?
Thank God the crew were experienced enough to take corrective action. How many Third World crews would have been able to do the same or ended up splattered all over the airfield perimeter?