AMR 587 Airbus Crash (merged)
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wsherif1: Before you threw the question back at me I had done a search of NASA without success.
I have now done another search under Wake Vortex and can still not find anything that suggests a wake vortex of 300ft/sec at an approx distance of 4 miles behind the target aircraft.
The only reference to speed I found was
"can exceed 150mph " (220ft/sec.), without a distance being specified.
Please improve my search skills and help me track down the source of your information.
I have now done another search under Wake Vortex and can still not find anything that suggests a wake vortex of 300ft/sec at an approx distance of 4 miles behind the target aircraft.
The only reference to speed I found was
"can exceed 150mph " (220ft/sec.), without a distance being specified.
Please improve my search skills and help me track down the source of your information.
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Eidolon,
Your comment,
"There is no suggestion by any party to say the aircraft experienced 0.8g acceleration in yaw (without any movement of the rudder.")????
The NTSB says at 16.04.5 the FDR shows lateral acceleration increases to 0.8g, yaw rate of 10 degrees/sec. left bank through 25 deg WITH PILOT APPLYING RIGHT WHEEL, pitch down -30 deg.! (Textbook description of a, Yaw induced left Dutch Roll!) (Reading from FDR released by the NTSB at 2/8/02 press conference.)
Your comment,
"There is no suggestion by any party to say the aircraft experienced 0.8g acceleration in yaw (without any movement of the rudder.")????
The NTSB says at 16.04.5 the FDR shows lateral acceleration increases to 0.8g, yaw rate of 10 degrees/sec. left bank through 25 deg WITH PILOT APPLYING RIGHT WHEEL, pitch down -30 deg.! (Textbook description of a, Yaw induced left Dutch Roll!) (Reading from FDR released by the NTSB at 2/8/02 press conference.)
Last edited by wsherif1; 28th Nov 2004 at 07:38.
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From AIM (7-3-3. Vortex Strength):
http://www.faa.gov/ATpubs/AIM/Chap7/aim0703.html#7-3-3
There is a similar sentence in a 1991 FAA advisory circular:
http://www.asy.faa.gov/safety_products/WakeAC.html
Peak vortex tangential speeds exceeding 300 feet per second have been recorded.
There is a similar sentence in a 1991 FAA advisory circular:
Peak vortex tangential speeds up to almost 300 feet per second have been recorded.
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Henry Crun,
Your comment,
"Please improve my search skills and help me track down the source of your information."
From AIM (7-3-3. Vortex Strength):
Quote:
Peak vortex tangential speeds exceeding 300 feet per second have been recorded.
There is a similar sentence in a 1991 FAA advisory circular:
Your comment,
"Please improve my search skills and help me track down the source of your information."
From AIM (7-3-3. Vortex Strength):
Quote:
Peak vortex tangential speeds exceeding 300 feet per second have been recorded.
There is a similar sentence in a 1991 FAA advisory circular:
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AA587 Crow Instability and Wake Turbulence Augmentation
wsherif1, cringe, henry crun
Suggest looking at:
AA587 Crow Instability and Wake Turbulence Augmentation
Are Wake Turbulence Standards Adequate?
UNC
Suggest looking at:
AA587 Crow Instability and Wake Turbulence Augmentation
Are Wake Turbulence Standards Adequate?
UNC
wsherif1,
I cannot find comments to that effect or in that context on the NTSB web site.
I had another look at the aimantions of the pilot inputs and the FDR recreation from http://www.ntsb.gov/events/2001/AA58...d_mtg_anim.htm without any conclusion to support the statement you made.
I am aware that the NTSB have said the probable cause is as follows :
The following conclusions were also drawn :[list=1][*]The captain and the first officer (the flying pilot) were properly certificated and qualified under Federal regulations. No evidence indicates any preexisting medical conditions that may have adversely affected the flight crew’s performance during the flight. Flight crew fatigue was not a factor in this accident.
[*]The accident airplane was properly maintained and dispatched in accordance with Federal regulations.
[*]The air traffic controllers who handled American Airlines flight 587 were properly trained and qualified. The local controller complied with Federal Aviation Administration wake turbulence spacing requirements when handling flight 587 and Japan Air Lines flight 47, which departed immediately before flight 587.
[*]The witnesses who reported observing the airplane on fire were most likely observing a fire from the initial release of fuel or the effects of engine compressor surges.
[*]Flight 587’s cyclic rudder motions after the second wake turbulence encounter were the result of the first officer’s rudder pedal inputs.
[*]Flight 587’s vertical stabilizer performed in a manner that was consistent with its design and certification. The vertical stabilizer fractured from the fuselage in overstress, starting with the right rear lug while the vertical stabilizer was exposed to aerodynamic loads that were about twice the certified limit load design envelope and were more than the certified ultimate load design envelope.
[*]The first officer had a tendency to overreact to wake turbulence by taking unnecessary actions, including making excessive control inputs.
[*]The American Airlines Advanced Aircraft Maneuvering Program ground school training encouraged pilots to use rudder to assist with roll control during recovery from upsets, including wake turbulence.
[*]The American Airlines Advanced Aircraft Maneuvering Program excessive bank angle simulator exercise could have caused the first officer to have an unrealistic and exaggerated view of the effects of wake turbulence, erroneously associate wake turbulence encounters with the need for aggressive roll upset recovery techniques, and develop control strategies that would produce a much different, and potentially surprising and confusing, response if performed during flight.
[*]Before the flight 587 accident, pilots were not being adequately trained on what effect rudder pedal inputs have on the A300-600 at high airspeeds and how the airplane’s rudder travel limiter system operates.
[*]The A300-600 rudder control system couples a rudder travel limiter system that increases in sensitivity with airspeed, which is characteristic of variable stop designs, with the lightest pedal forces of all the transport-category aircraft evaluated by the National Transportation Safety Board during this investigation.
[*]The first officer’s initial control wheel input in response to the second wake turbulence encounter was too aggressive, and his initial rudder pedal input response was unnecessary to control the airplane.
[*]Certification standards are needed to ensure that future airplane designs minimize the potential for aircraft-pilot coupling susceptibility and to better protect against high loads in the event of large rudder inputs.
[*]Because of its high sensitivity (that is, light pedal forces and small pedal displacements), the A300-600 rudder control system is susceptible to potentially hazardous rudder pedal inputs at higher airspeeds.
[*]To minimize the potential for aircraft-pilot coupling events, transport-category pilots would benefit from training about the role that alternating full control inputs can play in such events and training that emphasizes that alternating full rudder inputs are not necessary to control a transport-category airplane.
[*]There is a widespread misunderstanding among pilots about the degree of structural protection that exists when full or abrupt flight control inputs are made at airspeeds below the maneuvering speed.
[*]Federal Aviation Administration standards for unusual attitude training programs that take into account industry best practices and are designed to avoid inaccurate or negative training would lead to improvement and standardization of industry training programs.
[*]The use of lower levels of automation, such as simulators without motion or simple computer screen displays, may be more appropriate to provide the necessary awareness training with less danger of introducing incorrect information. [/list=1]
I cannot find comments to that effect or in that context on the NTSB web site.
I had another look at the aimantions of the pilot inputs and the FDR recreation from http://www.ntsb.gov/events/2001/AA58...d_mtg_anim.htm without any conclusion to support the statement you made.
I am aware that the NTSB have said the probable cause is as follows :
The National Transportation Safety Board determines that the probable cause of this accident was the in-flight separation of the vertical stabilizer as a result of the loads beyond ultimate design that were created by the first officer’s unnecessary and excessive rudder pedal inputs. Contributing to these rudder pedal inputs were characteristics of the A300-600 rudder system design and elements of the American Airlines Advanced Aircraft Maneuvering Program.
[*]The accident airplane was properly maintained and dispatched in accordance with Federal regulations.
[*]The air traffic controllers who handled American Airlines flight 587 were properly trained and qualified. The local controller complied with Federal Aviation Administration wake turbulence spacing requirements when handling flight 587 and Japan Air Lines flight 47, which departed immediately before flight 587.
[*]The witnesses who reported observing the airplane on fire were most likely observing a fire from the initial release of fuel or the effects of engine compressor surges.
[*]Flight 587’s cyclic rudder motions after the second wake turbulence encounter were the result of the first officer’s rudder pedal inputs.
[*]Flight 587’s vertical stabilizer performed in a manner that was consistent with its design and certification. The vertical stabilizer fractured from the fuselage in overstress, starting with the right rear lug while the vertical stabilizer was exposed to aerodynamic loads that were about twice the certified limit load design envelope and were more than the certified ultimate load design envelope.
[*]The first officer had a tendency to overreact to wake turbulence by taking unnecessary actions, including making excessive control inputs.
[*]The American Airlines Advanced Aircraft Maneuvering Program ground school training encouraged pilots to use rudder to assist with roll control during recovery from upsets, including wake turbulence.
[*]The American Airlines Advanced Aircraft Maneuvering Program excessive bank angle simulator exercise could have caused the first officer to have an unrealistic and exaggerated view of the effects of wake turbulence, erroneously associate wake turbulence encounters with the need for aggressive roll upset recovery techniques, and develop control strategies that would produce a much different, and potentially surprising and confusing, response if performed during flight.
[*]Before the flight 587 accident, pilots were not being adequately trained on what effect rudder pedal inputs have on the A300-600 at high airspeeds and how the airplane’s rudder travel limiter system operates.
[*]The A300-600 rudder control system couples a rudder travel limiter system that increases in sensitivity with airspeed, which is characteristic of variable stop designs, with the lightest pedal forces of all the transport-category aircraft evaluated by the National Transportation Safety Board during this investigation.
[*]The first officer’s initial control wheel input in response to the second wake turbulence encounter was too aggressive, and his initial rudder pedal input response was unnecessary to control the airplane.
[*]Certification standards are needed to ensure that future airplane designs minimize the potential for aircraft-pilot coupling susceptibility and to better protect against high loads in the event of large rudder inputs.
[*]Because of its high sensitivity (that is, light pedal forces and small pedal displacements), the A300-600 rudder control system is susceptible to potentially hazardous rudder pedal inputs at higher airspeeds.
[*]To minimize the potential for aircraft-pilot coupling events, transport-category pilots would benefit from training about the role that alternating full control inputs can play in such events and training that emphasizes that alternating full rudder inputs are not necessary to control a transport-category airplane.
[*]There is a widespread misunderstanding among pilots about the degree of structural protection that exists when full or abrupt flight control inputs are made at airspeeds below the maneuvering speed.
[*]Federal Aviation Administration standards for unusual attitude training programs that take into account industry best practices and are designed to avoid inaccurate or negative training would lead to improvement and standardization of industry training programs.
[*]The use of lower levels of automation, such as simulators without motion or simple computer screen displays, may be more appropriate to provide the necessary awareness training with less danger of introducing incorrect information. [/list=1]
Cejkovice: You raised an interesting subject.
You said that pilots are used "to the feel" of an aircraft.
How often do pilots training on an FMC airplane actually fly the simulator by hand, without engaging an autopilot and/or autothrottles? Even in the US, where all but a few pilots with major airlines have thousands of hours experience in multi-turbine planes, there are stories that many training programs rarely want pilots to hand fly the plane up to 16,000 feet, for example, OR even the whole way around a quick simulator "visual" pattern. I doubt that they do it on the A-320 or the older FEDEX A-310/300 etc or MD-11/10.
Many pilots hand-fly 757s to at least 14,000-FL180 after Initial Op. Experience is over, but this is rare during simulator or IOE, is it not? The focus of the training consists mostly of learning the automation to comply with ATC (we never used VS mode except below 10.000' or on a non-precison approach)-but NOT to hand-fly up to 320 knots and even 12,000 feet, based on my experience several years ago in the 757.
Do many foreign airlines avoid letting pilots ever fly without autopilots etc fully engaged? If this is the case with twin-engine turboprops and smaller jets, then when can pilots acquire solid experience which they can quickly apply if they must turn off most automation during a system problem (i.e. slow autothrottle response, sloppy level-off, or when the AIRCRAFT, for a split second or more, tries to "throttle up" while using MANUAL throttles (!) at the normal glideslope intercept altitude etc?
You said that pilots are used "to the feel" of an aircraft.
How often do pilots training on an FMC airplane actually fly the simulator by hand, without engaging an autopilot and/or autothrottles? Even in the US, where all but a few pilots with major airlines have thousands of hours experience in multi-turbine planes, there are stories that many training programs rarely want pilots to hand fly the plane up to 16,000 feet, for example, OR even the whole way around a quick simulator "visual" pattern. I doubt that they do it on the A-320 or the older FEDEX A-310/300 etc or MD-11/10.
Many pilots hand-fly 757s to at least 14,000-FL180 after Initial Op. Experience is over, but this is rare during simulator or IOE, is it not? The focus of the training consists mostly of learning the automation to comply with ATC (we never used VS mode except below 10.000' or on a non-precison approach)-but NOT to hand-fly up to 320 knots and even 12,000 feet, based on my experience several years ago in the 757.
Do many foreign airlines avoid letting pilots ever fly without autopilots etc fully engaged? If this is the case with twin-engine turboprops and smaller jets, then when can pilots acquire solid experience which they can quickly apply if they must turn off most automation during a system problem (i.e. slow autothrottle response, sloppy level-off, or when the AIRCRAFT, for a split second or more, tries to "throttle up" while using MANUAL throttles (!) at the normal glideslope intercept altitude etc?
Last edited by Ignition Override; 29th Nov 2004 at 05:09.
