Heathrow BA plane crash caused by 'unknown' ice fault

[zoot horn rollo]

http://news.bbc.co.uk/1/hi/england/london/8504734.stm

http://www.aaib.gov.uk/publications/...010_g_ymmm.cfm



edit: AAIB report now available in full

[Grey Area]

It's not exactly an unknown problem.

From the first linked article: "On 28 November 28 2008 a Delta Airlines Boeing 777 suffered a similar ice problem while flying over the USA, which prompted an investigation by America's National Transportation Safety Board, with the AAIB having an accredited representative. "

This was posted on the BBC News website almost 12 months ago: http://news.bbc.co.uk/1/hi/uk/7941137.stm

[KabirT]

This seems similar to the 737 rudder problems that caused the USAir 427 crash? Just without the horrific consequences that the 737 faced?

[steve rowell]

I was talking to Peter Burkill online a few weeks back..hell of a nice chap

[Bmused55]

Originally Posted by KabirT

This seems similar to the 737 rudder problems that caused the USAir 427 crash? Just without the horrific consequences that the 737 faced?

How so?! I realy do not get your reasoning on this one.

The icing issue isn't sending the planes into an incontrollable dive.
There are been no fatalities.
The only similarity is that the name Boeing appears on the model of aircraft.

[KabirT]

No..not literally. I was talking about the similarity between the chain of events. As I said the problems progression seems to be similar on those lines except the seriousness of the problem.

[zoot horn rollo]

The reference to the 'unknown' ice fault is not that it had not occurred in service before, as clearly it had, but more that it was not an event that had been foreseen or contemplated by the original design team.

[Red Hunter]

For all of you knowledgable chaps, just how much of a risk is this problem? Is it very uncommon and very unlikely? Is it completely avoidable? you have referred to another incident in which it might have been a cause.

[Grey Area]

Originally Posted by zoot horn rollo

The reference to the 'unknown' ice fault is not that it had not occurred in service before, as clearly it had, but more that it was not an event that had been foreseen or contemplated by the original design team.

Ah, fair enough then.

[PMN]

Originally Posted by JoeyR

For all of you knowledgable chaps, just how much of a risk is this problem? Is it very uncommon and very unlikely? Is it completely avoidable? you have referred to another incident in which it might have been a cause.

I certainly don't count as a "knowledgeable person", but looking at the 15 year operational history of the 777 this problem (or it's assumed to be this problem) only seems to have occurred three times, and now the cause has been isolated I'm sure steps will be taken to ensure it doesn't happen again. In the other two incidents (Delta and American Airlines) it only affected one engine and seemed to rectify itself (although the American was on final at the time just as G-YMMM had been at Heathrow). Hopefully we won't hear of any more incidents like these!

Paul

[hangarone]

The 727 had dedicated fuel heaters, and it never suffered from this problem.

[Red Hunter]

Thanks, PMN - that sounds reassuring.

[Cking]

All modern jet airliners have fuel/oil heat exchangers. Every daily check the fuel tanks are checked for water contamination. Water in the fuel system and fuel "waxing" is known about and delt with by both of the previous things.
If this was a problem with ice in the fuel, why didn't all the 777's flying into Heathrow that day do the same thing?

Rgds Cking

[symon]

Indeed, major steps have been taken to rectify this issue. Not long after the accidents/incidents, procedures were put in place to prevent the build up of ice blocking the fuel flow. Physical modifications have now returned the fuel operational flow to its 'original' perceived reliability and improved on it. I don't know how to explain the randomness of the events though.