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[Nickbat]

..and I can understand why!

Instead of following the typical climb profile, the first officer - whose aerobatic experience meant he was familiar with buffet - controlled the aircraft through the stall warning and buffeting by executing a shallower climb, while the commander supported the manoeuvre by calling out heights above ground.

The slats stayed retracted for a total of 23s. They started to redeploy 7s after the jet became airborne - as the undercarriage was retracting, at a height of 56ft - and were fully extended 9s later.

http://www.flightglobal.com/articles/2010/06/26/343738/ba-747-crew-commended-for-escaping-near-stall-on-take-off.html

 

[Sixstring]

Excellant......
Outstanding flying.

Having done a little flying myself, That was a brilliant bit of "seat-of-the-pants" piloting.

I'm sure Debs will agree too.

[Dishevelled Den]

Seems to have been a very able piece of 'airperson-ship' 8-)

I was concerned to read this further down in the report;

In its inquiry report into the 11 May 2009 incident, the CAA says the crew had "no notion" that the slats had retracted before rotation. There is no separate indication in the cockpit for leading-edge slat position

......but at least this previously unknown condition seems to have been attended to;

Boeing subsequently developed a safety bulletin for Rolls-Royce-powered 747-400s to disable this reverser-based automated stowing.

......although I wonder how many more such conditions lurk within the mechanisms of these sophisticated aircraft?

[Kevin Wood]

......although I wonder how many more such conditions lurk within the mechanisms of these sophisticated aircraft?

Hmm. ever more complex aircraft operated by fewer crew. Doubt this would have happened if there'd been a flight engineer on board.

It amazes me that the automated systems on these aircraft can't differentiate between radically different phases of flight. Retraction of the slats - something that's desirable when engaging reverse thrust during the landing phase of flight but potentially disastrous during take-off yet an input from a faulty transducer somehow overrides every other clue that the aircraft is actually taking off.

Must have been a very worrying few seconds for the crew.

Kevin

[Entwood]

......although I wonder how many more such conditions lurk within the mechanisms of these sophisticated aircraft?

Hmm. ever more complex aircraft operated by fewer crew. Doubt this would have happened if there'd been a flight engineer on board.

It amazes me that the automated systems on these aircraft can't differentiate between radically different phases of flight. Retraction of the slats - something that's desirable when engaging reverse thrust during the landing phase of flight but potentially disastrous during take-off yet an input from a faulty transducer somehow overrides every other clue that the aircraft is actually taking off.

Must have been a very worrying few seconds for the crew.

Kevin

As an ex-flight engineer I would love to agree with you .. but good as we are, we can only go by the information provided .. and with no "slat position indicator" even an FE would not have known the slats were in the wrong place.

[Kevin Wood]

As an ex-flight engineer I would love to agree with you .. but good as we are, we can only go by the information provided .. and with no "slat position indicator" even an FE would not have known the slats were in the wrong place.

I'm just wondering if there would have been such an indication, and the facility (and spare crew workload) to recognise and override the automated system in such an instance?

Not that I know a great deal about it.. These aircraft with engines'll never catch on.

Kevin

[Dishevelled Den]

......although I wonder how many more such conditions lurk within the mechanisms of these sophisticated aircraft?

Hmm. ever more complex aircraft operated by fewer crew. Doubt this would have happened if there'd been a flight engineer on board.

It amazes me that the automated systems on these aircraft can't differentiate between radically different phases of flight. Retraction of the slats - something that's desirable when engaging reverse thrust during the landing phase of flight but potentially disastrous during take-off yet an input from a faulty transducer somehow overrides every other clue that the aircraft is actually taking off.

Must have been a very worrying few seconds for the crew.

Kevin

As an ex-flight engineer I would love to agree with you .. but good as we are, we can only go by the information provided .. and with no "slat position indicator" even an FE would not have known the slats were in the wrong place.

That's a valid point E - on the question of the impressive advance in flight deck technology is there a case for having a FE remain as a third set of eyes or are the systems sufficiently competent to go with the two person crew? 

[Chris_H]

Seems to have been a very able piece of 'airperson-ship' 8-)

I was concerned to read this further down in the report;

In its inquiry report into the 11 May 2009 incident, the CAA says the crew had "no notion" that the slats had retracted before rotation. There is no separate indication in the cockpit for leading-edge slat position

......but at least this previously unknown condition seems to have been attended to;

Boeing subsequently developed a safety bulletin for Rolls-Royce-powered 747-400s to disable this reverser-based automated stowing.

......although I wonder how many more such conditions lurk within the mechanisms of these sophisticated aircraft?

It requires 'thinking outside the box' to envisage the multitude of erroneous conditions that can potentially occur.  Which is what I presume, designers of safety-critical systems are required to do anyway.

As an aside; I wouldn't describe a 747 as sophisticated nowadays.

Thank God that something well-designed (the aircrew) was able to over-rule.... makes you laugh in a way.

This pilot earned his salary IMO.  Quite a few airline pilots do aerobatics in their leisure time and it looks as if it should be encouraged?

[Entwood]

As an ex-flight engineer I would love to agree with you .. but good as we are, we can only go by the information provided .. and with no "slat position indicator" even an FE would not have known the slats were in the wrong place.

I'm just wondering if there would have been such an indication, and the facility (and spare crew workload) to recognise and override the automated system in such an instance?

Not that I know a great deal about it.. These aircraft with engines'll never catch on.

Kevin

From the report it would appear not, no indications of leading edge slat positions, and all actions controlled by a "logic" circuit - which failed, and part of which has now been changed !!

Just spoke to a 747 pilot friend ...  apparently the "old" 747's that carried FE's (some years ago) has slat indicators as "there was someone to read them" (!!!!) but on the 2 man flight deck they are fully automated.

[Entwood]

@zulu : The FE was, in essence, a "systems analyist" in flight -- we only took things apart and fixed them (or not) on the ground. So we would take information in from various instruments, analyse that information and using the logic we were trained with, develop a scenario, from which, again using logic, we would advise the crew on a course of action. We also carried manuals to which we could refer to for slowly developing problems, and reference cards for fast developing emergencies.

The modern computer does, unfortunately, exactly the same thing, but faster and more clinically, and without the risk of a "hangover" . The downside is that the computer will "believe" every indication (sensor output) where an experienced FE could say .. "ignore that it can't happen - must be a guage"

The assumption here is that the programme writer has "foreseen" every possible permutation ... which we know cannot happen

@Chris - many airline pilots are ex-RAF and not just transport aircraft ... my money is the first officer in this case was either ex-fast jet or maybe even ex-red arrows