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Old 1st Apr 2004, 21:24
  #45 (permalink)  
DouglasDigby
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A340 - CLK - windshear (microburst!)

Ramrise, can't find any report, but attended a company briefing where the A340 "windshear" incident was most comprehensively reviewed. Managed to trawl up some of the information, but please bear in mind that this is by no means categoric or the entire story!

They had a descent at 2000 feet/min over the sea – with a very low RA height. It was the second approach (the first had resulted in 2 windshear warnings, with subsequent go-around). Through a combination of circumstances (Terminal Doppler Weather Radar going down – it didn’t like the 75 knots of wind, local anemometers that wouldn’t report winds above 30 knots – a computer “fudge” due to geographical siting locations, and runway change), the crew (no fault of their own) ended up in worse circumstances than on their first approach. Most importantly, all weather warnings on the ATIS and from ATC controllers referred to “microburst;” this flavoured the crew expectations towards convective TS activity, whereas the actual conditions were severe windshear. There are numerous other facets that I can't quote or cannot remember!! However, the very positive aspect was that the software-related “protection” features of the A340 almost certainly saved the day. Similar conditions were programmed into B747 simulator, a ditching every time! IIRC, major changes for wind reporting/calculations came into effect at CLK shortly afterwards (don't go there with current company!).

Anyway, back to the thread - if terrain isn't an issue, why the heck is full TOGA power needed?? Many go-around altitudes will be reached in seconds if carrying out a "missed" from DA, light aircraft + full power = ROC like a rocket! Frightens the punters down the back too!!