Posted on 01/19/2008 6:36:09 AM PST by barryg
1. Birds
Could birds have got into the engine? "Bird Strike" is a well-known problem in aviation. Even a few birds could break a component which would be sucked into the rest of the engine. # Co-pilot saved stricken Heathrow airliner
They can also interrupt the airflow, which is vital. The damage would depend on how many had been ingested.
Accident investigators search the area for debris from the crashed jet Accident investigators search the surrounding area for debris from the crashed jet
The strange sound of the engine has given this theory some credence. But Heathrow is regarded as one of the safest airports in the country as far as bird strike is concerned and there have been no reports of any feathers being found.
John Ling, the head of transport at the Institution of Mechanical Engineers, advised caution: "While bird strikes can cause considerable damage, they don't normally have such a dramatic impact."
2. Fuel contamination
This emerged as a strong contender last night following the release of the investigators' report. advertisement
Industry insiders have suggested that a contaminant, possibly water, may have leaked into the fuel tank and caused the engines to fail.
Pilots believe it is possible that as the plane descended, ice on the wings thawed into slush and then seeped into the engines. It is also possible that any contamination may have occurred during fuelling.
3. Electrical failure
This is still a possibility and one which will be closely examined by the investigators, who will find vital clues from the flight recorder, evidence from the control tower and the pilot's own testimony.
4. Computer failure
Aircraft rely heavily on computer systems and a sudden failure would cause serious problems.
This was dismissed by David Learmount, the operations and safety editor of Flight International magazine. "There is not just one computer, there are a whole series of back-ups," he said. "It is like a lift, which does not have one cable but has four. All critical systems must have back-ups."
5. Boeing 777 design fault
Could there be a fundamental problem with the airliner? There have been reports of about a dozen incidents of electrical systems overheating.
But the Boeing 777 is regarded as one of the safest aircraft in the air. There are currently 667 in service and, until Thursday, the planes had not been involved in a serious incident.
"These things have been flying for a long time, the fact that the fuselage stayed intact is a testimony to the reliability of the aircraft," said Mr Ling.
6. Accidental jamming of onboard systems by police because the Prime Minister was nearby
A far-fetched theory which suggests that the police may have blocked mobile phones in the area as the Prime Minister's motorcade drove past. This in turn would, it is claimed, have created a systems failure on a plane overhead. This is unlikely to the point of impossibility.
"I am sure other people would have noticed and more than one plane would have come down," said Mr Ling.
7. Human error
Did the pilot make a fatal error on approach? At Kegworth in 1989, a pilot facing engine failure shut down the wrong one, leaving the plane without power.
This seems unlikely. John Coward, the senior first officer who landed the aircraft, had 11 years' experience on Boeing 777s and 15 as a pilot. Peter Burkill, the captain, had 20 years' experience with BA. Given the length of the flight it is normal practice for the pilot, senior first officer and first officer to share duties. They were also landing at BA's home airport.
Note there was no fire at the crash site.
“Accidental jamming of onboard systems by police because the Prime Minister was nearby.”
If that was the cause, no one will ever admit it.
I notice that one of the possible causes is fuel contamination. Since the flight originated from Beijing, that is my prediction, although it seems doubtful that both fuel lines would beceome clogged at the same time. Possibly, they simply ran out of fuel.
What, no speculation on passengers turning on their cell phones???
Very good post. My thoughts lean toward fuel.
As fuel was used during flight, it was replaced with air. It might have been this air, contaminating the remaining fuel, that got ingested into these two engines causing loss of power.
Me too ... there is too much redundancy for both engines to go out simultaneously, unless there is a common cause, ran out of fuel. Long flight, so the odds are high that fuel use, or loss in flight may be the cause. A fuel leak undetected by the computers would do that ... No fire, points the finger.
It’s hard to believe they weren’t warned that they weren’t low on fuel.
I take it that there was some kind of a problem at the airport?
I like possibility no, 6, though, for it’s simplicity. I think radio interference is unpredictable enough (what may block it, what may amplify it etc...) to serve as a cause. At any rate I doubt the cause will rise above something mundane.
May not be, but it would be the first thing I wrote down.
The “ran out of fuel” option is the best.
Both engines hit the ground with damage that was strongly correlated to “no rotation/slow rotation at time of impact”. This implies a common fault mode.
Both engines fail + no fire + slow engine rotation at crash + no response from throttle = no fuel.
My gueas is that it could have been a liters-quarts conversion error in China.
I'm glad they put that last plane into service.
My first guess would be fuel from the limited description given.
Given the limited info, I’m guessing that this is a sidebar to a more detailed story.
A "you aren't low on fuel" warning would get pretty tedious on a long flight. /wisearse reply
What happens to a plane wreck?
http://news.bbc.co.uk/1/hi/magazine/7196208.stm
It will be removed from the runway and taken away to be broken up
The undamaged components will be sold as spares
Any scrap metal will be disposed of by a specialist
What? How can this be impossible. We've been told for years that cell phones and cd players could drop a plane straight outta the sky...you mean military grade jammmers can't? Who ever would have thought that?
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