Crosswind From United Kingdom, joined Nov 2000, 2572 posts, RR: 59 Reply 4, posted (11 years 6 months 2 weeks 13 hours ago) and read 1270 times:
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Yes, the fin has been recovered from Jamaica Bay, however, from the photo you can see it is intact, but missing the rudder. It could have been thrown clear on impact, or more likely separated due to excessive aerodynamic loads in the dive to the ground.
Whatever, the fin being undamaged would suggests it was not a factor in the cause of the accident, wouldn't it?
Artsyman From United States of America, joined Feb 2001, 4741 posts, RR: 43 Reply 5, posted (11 years 6 months 2 weeks 13 hours ago) and read 1248 times:
I just fail to see how this could be a mechanical issue and not a terrorist issue. If the plane exploded in mid-air which is what it would take for the tail to be found as far away from the fuselage as it was, what made it explode ? uncontained engine failure wouldnt cause this, therefore I cant help but think it isnt a machanical failure
Crosswind From United Kingdom, joined Nov 2000, 2572 posts, RR: 59 Reply 6, posted (11 years 6 months 2 weeks 13 hours ago) and read 1219 times:
I'm sure you're familiar with the JAL 747 that suffered a rear pressure-bulkead failiure - the plane crashed into a mountain, the tail was found relatively undamaged many miles away in Tokyo Bay. Or what about the TWA 747 that exploded in mid-flight, everyone said "Another Lockerbie" because of the ferocity of the explosion and breakup. In the end the cause of the accident was an explosion in the centre fuel tank.
You can't draw inferences about the cause of an accident because of superficial evidence. As I said above, aerodynamic loads in an extreme dive, beyond the design limits of the aircraft could cause it to fail.
In the 1960s a Braniff BAC1-11 lost it's tail over Iowa due to an undraft from a thunderstorm, and a BOAC 707 lost it's tail due to a montain wave over Japan. Tails are quite vulnerable structures under extreme aerodynamic loads - they aren't built to withstand the same forces as wings.
Chiawei From United States of America, joined Nov 2000, 884 posts, RR: 2 Reply 7, posted (11 years 6 months 2 weeks 13 hours ago) and read 1213 times:
Depends. This accident now looks very similar to the Lauda Air crash in 1991.
Could it just be the same reason that some how the left engine went into full-reverse during take off. In this car, the stress will cause the engine and left wing to break away. Moreover, the sudden assymetrical thrust would also result in high stress on the fuselage causing the tail to separate. Minute by minute, I really believe that this is now similar.
Does anyone know whether or not the Lauda 767 that broke apart over thailand was powered by CF6?
Crosswind From United Kingdom, joined Nov 2000, 2572 posts, RR: 59 Reply 8, posted (11 years 6 months 2 weeks 13 hours ago) and read 1175 times:
The Lauda B767 had PW4000 engines, the fault was unique to that engine series - it could not have affected the GE CF6, or the older PWJT9D on the 767.
Secondly, the extreme asymentric thrust caused the inflight breakup due to the high speed involved - the Lauda B767 was at high altitude at cruise speed when the breakup occured. The American A300 was at low atltude/low speed, the effects of asymetric thrust caused by reverser deployment would be insufficient to cause the sequence of events that befel the Lauda aircraft.
Chiawei From United States of America, joined Nov 2000, 884 posts, RR: 2 Reply 9, posted (11 years 6 months 2 weeks 13 hours ago) and read 1143 times:
May be I am an idiot asking this. But at higher altitude the indicated airspeed would not be much different than those of lower altitude. In other words the rate of air flow passing through the plane is quiet similar regardless of the height even though ground speed is very different. For example, at 41,000 ft, the indicated air speed of 250 knots is about 550 miles per hour. But at 500 ft it's about 260 miles per hour. But the speed of airflow is actually same. Hence I would assume that the force exerted by the airflow would be very similar.
So I believe that it is still quiet possible to have the same Lauda Air incident effect.
Beefmoney From United States of America, joined Oct 2000, 1111 posts, RR: 4 Reply 11, posted (11 years 6 months 2 weeks 12 hours ago) and read 1103 times:
Dispite what you have said, after thinking about it, the reverser malfunction seems the most resonable. I mean, 200-250 kts, one reverser opens, causes A300 to yaw wildly, aerodynamic forces cause vertical stabilizer, engine, maybe other parts, to break off. Eyewitness say that it hit the ground at a very steep angle and not a shallow angle, which would indicate a stall/spin caused by what ive mention above.
Spacecadet From United States of America, joined Sep 2001, 3251 posts, RR: 14 Reply 13, posted (11 years 6 months 2 weeks 12 hours ago) and read 1063 times:
AFAIK all modern passenger a/c are designed (possibly even required) to operate with reversers deployed in-flight. It's not even entirely unusual for it to happen - the media made it out to be after the Lauda Air crash, but I mean, they use reversers occasionally as air brakes in some aircraft. I suppose in a twin-engine plane a surprise deployment would be a bit more troublesome than on a four-engine aircraft, but investigators determined that even the Lauda Air crash was avoidable if the pilot had taken immediate corrective action. They did not blame the crash on pilot error, however, because there was no training program in place for this kind of failure at the time. Nowadays, pilots are trained for an in-flight failure of the reverser locking mechanism. It is not, by definition, a catastrophic failure, especially not at 270 knots. It would not cause an engine to separate from a wing, much less two of them (both engines were found in separate areas away from the main wreckage).
I dunno what caused this crash, but a reverser problem seems unlikely to me.
I'm tired of being a wanna-be league bowler. I wanna be a league bowler!
Chrisair From United States of America, joined Sep 2000, 1772 posts, RR: 4 Reply 15, posted (11 years 6 months 2 weeks 10 hours ago) and read 956 times:
I hate to speculate on this, but I can't understand how that tail didn't break up upon hitting the water. I know that honeycomb and aircraft material is incredibly strong, but hitting water is just the same as hitting concrete. Am I missing a piece of the puzzle here or what?
Chiawei From United States of America, joined Nov 2000, 884 posts, RR: 2 Reply 18, posted (11 years 6 months 2 weeks 9 hours ago) and read 916 times:
It's true that the modern aircraft were designed if thrust reverser was deployed while in flight.
But keep in mind, A300-600R is an early 80's design. Similar to 767-300 that went down in Thailand. The pilots were not able to respoind within 4-7 second window they had. What makes you think that an AA crew busy with departure tasks has time to react? The Lauda 767's reverse thrust deployed while in cruise. Totally different situation.
Also, at take off, the A300 is probably under full power. The 767 in cruise is probably operating at 75 to 80% N1. Hence totally different situation.
The more i look it, the more is looks like this is what exactly happened.
Positive rate From Australia, joined Sep 2001, 2143 posts, RR: 1 Reply 19, posted (11 years 6 months 2 weeks 9 hours ago) and read 913 times:
Does anyone think this crash resembles the crash of AA 191 in Chicago in 1979? In this case it may have been a catastrophic engine failure/fire but if the engine did physically seperate from the wing itself like in AA 191 then the hydraulic line would be severed causing the fluid to bleed out and in turn perhaps retraction of the slats on one wing causing that wing to stall and the a/c to go in vertically.
We're Nuts From United States of America, joined Jun 2000, 5705 posts, RR: 22 Reply 20, posted (11 years 6 months 2 weeks 8 hours ago) and read 881 times:
When USAir 427 went down, the FIRST thing they looked at was the engines. And when one was found in full-reverse, the case was almost closed. But it was later decided that the reverser got that way on impact. So it isn't totally unlikely.
BUT, I say leave the investigating to the professionals. No one here knows enough to understand what happened.