Tbird From United States of America, joined Oct 2001, 851 posts, RR: 20 Posted (12 years 4 weeks 20 hours ago) and read 1744 times:
More and more news agencies are reporting that wake turbulence may have been the cause of AA587's crash. CNN reported that a JAL 744 was only 90 sec's ahead of AA587 which is to close. I could see wake turbulence affecting a smaller jet but an A300 is rather large to be affected that much by a 744's wake. A few years ago NASA tested the wake turbulence theory in a USair crash where they flew two 737 less then a mile from each other and nothing major happened. What does everybody think of this theory?
777236ER From , joined Dec 1969, posts, RR: Reply 2, posted (12 years 4 weeks 20 hours ago) and read 1635 times:
Firstly, a question mark in front of the topic title?
Secondly, wake turbulance can be a big problem, usually though an A300 wouldn't be severly effected by even the greatest 747 wake turbulence/vortex. Lol, they'll be those who say the Wake Turbulance is the last resort of the NTSB. A 737 rudder hard-overs was blamed for a LONG time on wake vorticies.....
Chepos From Puerto Rico, joined Dec 2000, 6097 posts, RR: 11 Reply 3, posted (12 years 4 weeks 20 hours ago) and read 1618 times:
I think its better for people to stop speculating. I've heard so many things righht now from bird ingestion to a possible bomb. The media speculating and the people repeating this is making people not wanting to fly anymore.
FLYSAB From Belgium, joined Nov 1999, 106 posts, RR: 6 Reply 5, posted (12 years 4 weeks 19 hours ago) and read 1582 times:
Wake turbulence appears only from the point of rotation of the aircraft and stays under the flight path.
As the A300 rotated for sure (except if it took off from an intersection, but then you normally have to wait 3 minutes to start the take off roll behind a heavy) farther from the end of the runway than the 747, and then climbed with a better rate, the wake turbulence theory is probably not funded.
AWspicious From , joined Dec 1969, posts, RR: Reply 9, posted (12 years 4 weeks 19 hours ago) and read 1523 times:
I'm wouldn't be surprised if these pages are being monitored.... in light of recent developments. However, I gotta frown about the wake turbulence 'query'. The plane apparently only achieved an altitude of 2800 ft. Could it break apart so much and so soon? Would wake turbulence cause an A300 to break apart in the air? I'm of the assumption if the plane was to experience abnormal dynamic forces at a much higher altitude - say, the 13000 587 was cleared for - I could see there being enough time for the aircraft to become over stressed and break apart. Or, if it was wake turbulence at the suggested 2800 ft. she'd just loose it and fall to the ground.... intact till impact.
I wonder if perhaps the harmonics heard wasn't the tail section coming apart.... or, the initial cause of the tail section seperating.
Look, I don't think anyone is saying this or that IS what happened. all we're doing is wondering if this or that could possibly be a cause/contributing factor. Perhaps, some of us might learn something from these posts, no?
VirginFlyer From New Zealand, joined Sep 2000, 4537 posts, RR: 48 Reply 10, posted (12 years 4 weeks 19 hours ago) and read 1507 times:
I think the wake turbulence is credible, for exactly the reason you said: if it was wake turbulence at the suggested 2800 ft. she'd just loose it and fall to the ground.... intact till impact
The aircraft did come down intact, other than the vertical stabiliser and the engines. As said on other posts, if the vert stab somehow came off, the wake turbulence could have caused a side slip, which would have torn off the engines, and resulted in the rest of the aircraft coming down in one place. Which is pretty much what the debris field indicates.
The wake turbulence is definitely a factor. Whether it caused the vert stab to come off or not is unknown, but once the vert stab was gone, wake turbulence, or indeed any unsettled air, would have led to the crash.
"So powerful is the light of unity that it can illuminate the whole earth." - Bahá'u'lláh
AirT85 From , joined Dec 1969, posts, RR: Reply 11, posted (12 years 4 weeks 18 hours ago) and read 1477 times:
MSNBC reported that this airplane had an encounter with wake turbulence in 1994. Although the guy said the plane would have been inspected, which im sure it has been, could a second encounter possibly weaken the planes resistance to the vibration of encountering the wake? Im not trying to add to speculation, just asking a question.
Gyro From , joined Dec 1969, posts, RR: Reply 13, posted (12 years 4 weeks 18 hours ago) and read 1456 times:
I don't buy the wake turbulence story either... remember also that wake-turbulence descends at a rate of 200ft a minute I beleive... The JAL 747 must have taken off at a later point on the runway as the A-300 did... it had aslower rate of climb and subtract 300ft. for the 90 second time span. So unless the A-300 had a poor (which the A-300 doesn't) or restricted rate of climb, it seems very unlikely that it should have flown into the wake of the 747. Furthermore, and as stated before the A-300 must have been quite close to the 170,000kg. mark. To shake this heavy Airbus around and cause it to crash??? Very far fetched theory if you ask me...
Vibrations can mean many things such as an imminent stall or engine failure...
In the twin engine airplane I'm getting my multi rating in right now (Piper Aztec) if you are in a nose up attitude (climbing) and the critical engine fails and the pilots don't recognize or take appropriate action the plane will turn upside down and start an unrecoverable nose dive within seconds. Don't know if this is true in the A-300 however.
In my opinion, a plane that looses it's rudder will not go down nose first!!!
Don't know if this is true with the A-300 however...
Crank From Canada, joined May 2001, 1556 posts, RR: 2 Reply 14, posted (12 years 4 weeks 16 hours ago) and read 1426 times:
I dont know what a 744's turbuence could do on an A300, but I've experienced wake turbulence on a DC-9 this summer. It was about 90 seconds after takeoff, we entered turbulence for about 20 seconds and after it was gone. An Azores A310 had taken off about 2 or 3 minutes before us so I guess that's why.
Though, I hardly doubt this could cause an airplane to crash
FlightSimFreak From United States of America, joined Oct 2000, 720 posts, RR: 0 Reply 15, posted (12 years 4 weeks 15 hours ago) and read 1408 times:
In the AIM, Paragraph 7-3-2, it says "In rare instances a wake encounter could cause inflight structural damage of catastrophic proportions." Now, I'de have to agree that the A300 would be in the air long before that 747, and would be climbing much faster then him, so this is unlikely. But, if ATC had put a restriction on his climb for trafic or other reasons, he could have easily flown through that 747's wake.
Che From United States of America, joined Feb 2000, 537 posts, RR: 0 Reply 16, posted (12 years 4 weeks 15 hours ago) and read 1391 times:
A theory and just that. But its does need to be throughly invetigated. Any lead at this point should be followed up and investigated. Now is the time for the "I think this might have happend but why and how" and also the "this might of happend because of that" type of queations.
As for the wake turbulance theory. I think it should be checked out. The A300 is rather beefy and I don't see how a 747's wake could really affect an A300 too severely. But then again I could be wrong.
Tygue From Canada, joined Jul 1999, 222 posts, RR: 0 Reply 19, posted (12 years 4 weeks 14 hours ago) and read 1353 times:
Also, we can pretty much credit the crash itself with the loss of differential power compounded with no control over yaw, seeing as the number one engine and vertical stabilizer were both found over a mile from the main impact site. The aircraft should've been nearly impossible to control without two engines or a rudder.
What caused either of these events is beyond all of us.
However... aircraft engines are designed to fly up over the wing and fall to the ground SHOULD a seperation occur... this is what happened in the AA Flt 191 incident in 1979. The engine lifted and flew back as it should have, but struck the leading edge slats on it's way off which causes the slat disagreement. Perhaps something not unlike Flt191 occured in this case.
Although, had the engine hit the tail on the way off... would it not have as well been found in Jamaica Bay?
Nwafirstclass From , joined Dec 1969, posts, RR: Reply 23, posted (12 years 4 weeks 13 hours ago) and read 1324 times:
is wake turbulence like when a plane is by you and you get turbulence from it? when we were on the ground in mpls, i was going back to rochester and i was in an RJ-85(avro) and like a DC-9 or like a 727 was ahead of us and the plane was shaking, it was annoying