That BA Boeing 747 at Jo’burg – the report’s out

BA 747-400.jpgSome of you may remember an incident in May last year in which a British Airways Boeing 747-400 suffered an uncommanded slat-retraction on rotation at Johannesburg. I suggested that the aviating skills displayed by the crew were worthy of note.

Well, now the detailed South African CAA incident report is available and it confirms that it was every bit as hairy as it sounds and just how well the crew performed. A slightly complicated read, but worth the effort.

The earlier posts (which tell the tale rather more simply) are here and here.

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2 Responses to That BA Boeing 747 at Jo’burg – the report’s out

  1. David Connolly July 4, 2010 at 1:24 pm #

    This event was a close shave, shake-up call, by any metric. It is pertinent to contrast this event at FAJS at 5558 feet altitude in May with Lufthansa’s LH 540 accident on Nov 20 1974 at JKIA at 5330 feet altitude which stalled and crashed on takeoff with all LE Kruegers and Varcams’ retracted. The butcher’s bill was 59 fatalities of 157 on board. This was in affect a latent-lurking design error of the L/E and Takeoff Config warning system. BOAC and KLM had numerous previous clean L/E takeoffs from EGLL & EHAM. When starting the engines, the F/E closed the bleed valves for optimal P&W/GE N2 rotation. By the time the F/E completed the after start (relatively B-744 interminable) checklist, the F/O had set the flaps to 10 or 20 units. There being no duct pressure for the pneumatic L/E actuation, only the trailing edges moved into the flaps 10 takeoff setting. Probability and frequency eventually met, as they always do immutably, in Nairobi in Nov 20 1974, when nearly 5 years of luck ran out, as it always does.
    The relatively medium range of the B-747-100 permitted flaps 10 for most operations, particularly for hot and high variety of sub- Sahara Africa/Mexico and flaps 20 for runway limited operations. The weight and range span of the B-744 with almost universal 12000 ft runways still enabled both settings, but most operators opted for only flaps 20 to make tailstrike probability more foolproof. But the better fools of SIA invariably came along in NZAA on March 12 2003, with a spectacular VMU tail drag cutaway demo.
    The B-744 has about as much in common with it’s Classic heritage as Boeing current family members have with the German forebears, with primary pneumatic and slower secondary electric mode . But it is sobering and humbling to think that had the BA flight happened exactly as it did on a hotter Nov 11 2009 instead of May 11 2009, that auspicious 11-11 date would have more contemporary resonance of solemnity, gladly it is a lesson learned with calm hand and eye skill displayed. While the plane exhibited sluggish flying qualities, the crew did not.
    Another report worthy of consideration in a peripheral sense, was that concerning Virgin Atlantic’s B-744 G-VHOT from EGLL to KJFK on Dec 7 2006. It was low and cold, in it’s takeoff, and subsequent reject from a second takeoff because of a stall warning which operated 140 kts and 5 degrees pitch, because of a faulty vane sensor.
    Because of these learned events, a lot of briefings no include, including mine, F/O flying “After positive rate, without stall warning, I’ll call gear up, LNAV, THR REF, VNAV SPD, right A/P to CMD, at 1000 barometric, pitch 10, flaps 10, for tailstrike, immediate A/P ALT HLD”.
    If you find yourself massaging the yoke through molasses, the last thing you need is gear retraction drag. Though the SA CAA’s report illustrates a rather strange PDF format and despite it’s clear objectivity, a potential conflict of a regulator investigating the regulated, like FAA/NTSB, CAA/AAIB.

  2. mutuelle September 27, 2010 at 12:22 pm #

    I will surely read about the detailed South African CAA incident report.Hey NOble Shivy; do you really think that we cannot trust anybody who says ‘trust me’?I don’t think that this aplly to evryone.This depends on th epeople who is saying this.We must know someone quite well to trust him/her.

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