cometcomma
Banned
http://sites.google.com/site/eastern401/
SHORT VERSION
The plane was attempting a landing at Miami in 1972. After a turn on to final approach an warning occurred of the possibility of the nose gear not down and locked in position.
The plane was at 2000 feet on autopilot and making a go around while they put in a new nose gear light assembly. Previously they recycled the landing gear and still had a red light and needed 3 green lights for an indication of all landing gear down and locked.
A computer mismatch made a situation possible where the Autopilot was engaged by the Co-Pilot and Capt Loft accidently bumped the control column enough to disengage only the altitude hold only . The wide body went into a slight decent unnoticed as no one was flying the plane. Everyone was concerned with the light bulb assembly. The low altitude warning sounded and was unheard w all the other sounds. The low warning light was unnoticed as the flt engineer was below in the avionics bay trying to see with a telescopic sight if the nose gear was down and locked. There were a lot of chimes and bells for all sorts of things even things that mean every thing is fine.
Most likely the pilots side showed the craft decending but near the end the pilot was fiddling with the light. A mis-match with the computer control system probably made a situation where the co-pilots side might not have shown the plane in a descent. Even if the co-pilot was monitoring it
It was dark and over the everglades it was not possible to gauge the altitude of the plane by looking out the window. Failure of the flight crew to monitor the flight in the final minutes was the official cause of the crash.
Video RE-ENACTMENT OF THE CRASH- http://lessonslearned.faa.gov/L1011Everglades/reenactment_pop_up.htm
Chapter 3 - Flight 401 Crash Investigation and Findings--- long version
In the ensuing days, the NTSB conducted an investigation. They poked around the wreckage, interviewed survivors and witnesses and pored over the flight data. When investigators climbed into the crumpled hulk of the cockpit they found the control panel virtually intact. Loft's clock had stopped at 4:41:34 Greenwich time. (Calibrating to the nearest half second, the NTSB officially listed the moment of impact at 11:42:12.5 pm). The airspeed needle on Loft's side read 198 knots. The altitude select panel was set at two thousand feet. The nose gear light assembly was found jammed on its side and protruding a quarter of an inch out of its normal position. It contained two burned out light bulbs. All three throttles were in the full forward position, another indication that the pilots discovered the problem at the last moment and tried to pull out of it.
Angelo Donadeo, who had ridden in a cockpit jump seat was considered a crucial observer of what happened in the flight deck. He was interviewed on January 8th, while under heavy sedation in a Miami hospital. He signed the transcript of his testimony "reluctantly" because of his condition.
A peculiarity was discovered in the forward avionics bay; the two autopilot computers - those that controlled the plane's nose up and down attitude- were mismatched. One was a model 1-7, the other a Model 1-8. The difference between the two is that while one required 15 pounds of pressure on the control column to disengage the system, and the other required 20 pounds of pressure. Although the two computers were slightly different, both worked properly when tested, along with the five other computers that survived the crash. Eleven days after the crash, the NTSB loaded the surviving, mud stained autopilot computers into Aircraft N306EA, a sister ship to the one that crashed. Eventually all the evidence was presented in a public hearing held in the "Florida Room" of the Miami Springs Villas on March 5, 1973. By the time the meetings were over, the computer printouts from the Flight Data Recorder had been deciphered, and the voices of men now two months dead had been resurrected from the recording tapes. The evidence was abundant, and allowed investigators to develop a clear picture of what happened.
(Left: NTSB Map of the flight path of Flight 401)
The flight had been normal until the final approach into Miami. When Stockstill had looked at the landing gear indicator, the green light that identifies that the gear is properly locked in the 'down' position didn't illuminate. This failure has two possible explanations: either the gear wasn't down, or the light wasn't working. The pilots recycled the gear. When the light still did not come on, they aborted the landing to examine the situation. The tower instructed the L-1011 to pull out of its decent, climb to two thousand feet, and then make a U-turn and flight west over the darkness of the Everglades. The cockpit crew removed the light assembly and the flight engineer was dispatched into the hell hole to visually check if the gear was down.
Fifty seconds after reaching their assigned altitude and when the plane was halfway through its U-turn, the captain instructed Stockstill to put the L-1011 on autopilot. For the next eighty seconds the plane maintained level flight. Then it dropped one hundred feet, and then again flew level for two more minutes, after which it began a descent so gradual it could not be perceived by the crew. In the next seventy seconds, the plane lost only 250 feet, but this was enough to trigger the altitude warning "C-chord" chime, which is clearly heard on the CVR tapes. During the NTSB hearings, one Eastern captain testified that modern aircraft like the L-1011 have so many "clickers and clackers and bells," that the environment becomes filled with alert tones. "There should only be a warning when a warning need be, not when everything is ok," he noted. So it is possible that the soft, short audio alert went unnoticed in the din of cockpit noise. For whatever reason, there was no indication on Flight 401'a CVR recording that pilots heard the chime.
Meanwhile, the crew continued to attempt to reinstall the light assembly, which had become stuck in the panel ninety degrees clockwise, and would not come back out. During the NTSB hearings, an Eastern L-1011 captain noted that after the accident he and a mechanic tried to remove and replace the gear lamp only to find that, although it is square in shape, it has a small track and groove which only line up when the lamp is positioned correctly. He testified that the track starts about 50% of the way in, so if you start to push it in incorrectly, you don't realize it until the fixture is halfway in its housing and, by then, possibly jammed.
When Miami controller Charles H. Johnson, 40, inquired "how are things coming along out there," Eastern 401 was far below its assigned 2,000 foot altitude. The controller's handling of Eastern 401's go-around came under scrutiny at the NTSB hearings.
At the NTSB public hearings in March 1973, Mr. Johnson (photo: left) was asked why he didn't warn EAL 401 of its low altitude when he first noticed the 900 foot reading on his radar screen. Mr. Johnson testified that he wanted to see another sweep of the radar before making any judgements, that the readouts often differed from the actual altitude. "It's like when your TV picture rolls onece, you don't unplug it and take it to the TV man. You wait for a pattern of operation." He went on to say that in his opinion, the pilots appeared to be in command of the flight, as evidenced by their calm demeanor and rapid response to his instructions and questions. "There was no indication that the crew was unaware of its altitude," Johnson testified. This statement drew attention from an examiner who asked, "how would they indicate that they weren't aware of their altitude?" Johnson stammered for a moment and then sheepishly said, "I don't know."
Johnson's supervisor, Carl E. Joritz, Chief of the Miami Air Traffic Control Center, later pointed out that it is not the controller's duty to monitor the distance between the airplane and the ground, but rather the distance between airplanes. Although technically true at the time, the supervisor admitted that all controllers have a moral obligation to alert flight crews of an emergency situation. When Johnson was asked if he was treating Flight 401 as if it were an emergency situation, Johnson replied, "no." Joritz also testified that pilot groups have asked controllers not to bother them if they are having trouble landing.
(Ironically, on June 21, 1973, Charles Johnson was on duty in the Miami tower when a small plane crashed in the Everglades after having its radio tuned to the wrong frequency. Strangely, killed onboard the small plane was William Gregg, who was onboard another small plane December 29th and had reported seeing Flight 401 crash to the Miami tower.)
Both passengers and crew alike referred to the flight as being normal. "Routine," was a term often used. Flight Attendant Beverly Raposa (seen here in testifying at the hearing in the photo below), recalled that after the decent into Miami International had been aborted, the go-around flight was smooth, with no indication of there being anything wrong until impact.
So, why did the aircraft fall into the swamp that night?
The answer came in fragments. First, Eastern captain Daniel Gellert testified to the NTSB on February 6th that he had noticed that the altitude hold function could be disengaged by bumping the control column. Many pilots doubted Gellert's testimony, but the incident was strikingly similar to a situation encountered by Thomas Oakes, another Eastern pilot. Oakes had been one of the first captains qualified to fly the L-1011. He had the altitude hold function disengage on a flight on January 8th, ten days after the crash of flight 401. Oakes testified that he and the co-pilot noticed the malfunction and proceeded to reset the autopilot and then trip it off by bumping the control column several times. They noted this behavior in their log book. Although these seemed to be freak occurrences, Eastern took it seriously to send a printed notice to all it's L-1011 pilots on January 15th.
(As a side note, on April 8, 1983, Daniel Gellert appeared on NBC Television's Today show. On the show, Gellert discusses his decision to report the L-1011 altitude hold malfunction to the NTSB. Gellert explains that after discovering the problem he went to Eastern management and had a meeting with an airline VP regarding this issue. He claims that the problem went uncorrected. He points out that when Flight 401 crashed into the Everglades because of an altitude hold malfunction, he decided to go to the NTSB. He adds that shortly afterwards he was grounded and ordered to undergo psychological testing. Gellert maintains that he is a competent pilot who has a responsibility to his passengers and believes Eastern had given him a lot of flack and ruined his personal life. Gellert had apparently sued Eastern Airlines for liable around the same time as the NBC interview. In Eastern Air Lines, Inc. v. Gellert, 438 So. 2d 923 (Fla. 3d DCA 1983), the Third District Court of Appeal analyzed whether Eastern Air Lines was liable for defamatory statements madeto the press by the director of Eastern Air Lines' news bureau. The court held that Eastern Airlines could not liable for punitive damages absent proof that it was independently at fault).
Given this information, the NTSB hypothesized that Loft had probably bumped the control column when he turned to tell flight engineer Repo to "get down there and see if that goddamn nose wheel's down." The NTSB report continued: "If the captain had applied a force to the control wheel while turning to talk to the second officer, the altitude hold function might have been accidentally disengaged." The autopilot had apparently not turned off completely, but rather had switched into the "Control Wheel Steering" mode. The Whisperliner was no longer locked at two thousand feet, but would fly steadily at whatever level the pilots selected, purposefully or accidentally, by pressure on their control wheels. From this point on, even a slight nudge would be enough to edge the plane up or down.
An adjunct mystery which never really was solved was whether the altitude hold light extinguished when the function disengaged. In both Gellert's and Oakes' cases, they noted the autopilot light went out when they bumped the columns. But Stockstill might have been deceived by the mismatched autopilot computers on N310EA. There are two autopilot systems, an "A" and a "B." Because the computers were mismatched, Loft's side required 15 pounds of pressure to disengage, and Stockstill's side required 20 pounds of pressure. Had Loft bumped the column with more than 15, but less than 20 pounds of pressure, Loft's altitude hold light would have gone out, and Stockstill's light would remain on, giving him the erroneous impression that the autopilot was still engaged and holding the plane at two thousand feet. This could be the case, however, only if Stockstill had selected the "A" computer, which would be unlikely as the switch for the "A" computer is on Loft's side of the control panel. Either way, the NTSB did not believe that this was a critical factor in the accident.
One hundred and three people died. The fifteen million dollar aircraft was destroyed. And it al began with two burned out light bulbs with a replacement value of twelve dollars.
The landing gear was found to be in the down and locked position.
The report cited the cause of the crash as pilot error, specifically: "the failure of the flight crew to monitor the flight instruments during the final four minutes of flight, and to detect an unexpected descent soon enough to prevent impact with the ground. Preoccupation with a malfunction of the nose landing gear position indicating system distracted the crew's attention from the instruments and allowed the descent to go unnoticed."
In May, 1973, the NTSB made two recommendations regarding the design of the L-1011. First, that a light switch should be installed near the observation window in the avionics bay, and that the altitude alert light on Eastern's versions of the TriStar be modified so that they blink continuously when the jet deviates from the assigned altitude by more than 250 feet.
SHORT VERSION
The plane was attempting a landing at Miami in 1972. After a turn on to final approach an warning occurred of the possibility of the nose gear not down and locked in position.
The plane was at 2000 feet on autopilot and making a go around while they put in a new nose gear light assembly. Previously they recycled the landing gear and still had a red light and needed 3 green lights for an indication of all landing gear down and locked.
A computer mismatch made a situation possible where the Autopilot was engaged by the Co-Pilot and Capt Loft accidently bumped the control column enough to disengage only the altitude hold only . The wide body went into a slight decent unnoticed as no one was flying the plane. Everyone was concerned with the light bulb assembly. The low altitude warning sounded and was unheard w all the other sounds. The low warning light was unnoticed as the flt engineer was below in the avionics bay trying to see with a telescopic sight if the nose gear was down and locked. There were a lot of chimes and bells for all sorts of things even things that mean every thing is fine.
Most likely the pilots side showed the craft decending but near the end the pilot was fiddling with the light. A mis-match with the computer control system probably made a situation where the co-pilots side might not have shown the plane in a descent. Even if the co-pilot was monitoring it
It was dark and over the everglades it was not possible to gauge the altitude of the plane by looking out the window. Failure of the flight crew to monitor the flight in the final minutes was the official cause of the crash.
Video RE-ENACTMENT OF THE CRASH- http://lessonslearned.faa.gov/L1011Everglades/reenactment_pop_up.htm
Chapter 3 - Flight 401 Crash Investigation and Findings--- long version
In the ensuing days, the NTSB conducted an investigation. They poked around the wreckage, interviewed survivors and witnesses and pored over the flight data. When investigators climbed into the crumpled hulk of the cockpit they found the control panel virtually intact. Loft's clock had stopped at 4:41:34 Greenwich time. (Calibrating to the nearest half second, the NTSB officially listed the moment of impact at 11:42:12.5 pm). The airspeed needle on Loft's side read 198 knots. The altitude select panel was set at two thousand feet. The nose gear light assembly was found jammed on its side and protruding a quarter of an inch out of its normal position. It contained two burned out light bulbs. All three throttles were in the full forward position, another indication that the pilots discovered the problem at the last moment and tried to pull out of it.
Angelo Donadeo, who had ridden in a cockpit jump seat was considered a crucial observer of what happened in the flight deck. He was interviewed on January 8th, while under heavy sedation in a Miami hospital. He signed the transcript of his testimony "reluctantly" because of his condition.
A peculiarity was discovered in the forward avionics bay; the two autopilot computers - those that controlled the plane's nose up and down attitude- were mismatched. One was a model 1-7, the other a Model 1-8. The difference between the two is that while one required 15 pounds of pressure on the control column to disengage the system, and the other required 20 pounds of pressure. Although the two computers were slightly different, both worked properly when tested, along with the five other computers that survived the crash. Eleven days after the crash, the NTSB loaded the surviving, mud stained autopilot computers into Aircraft N306EA, a sister ship to the one that crashed. Eventually all the evidence was presented in a public hearing held in the "Florida Room" of the Miami Springs Villas on March 5, 1973. By the time the meetings were over, the computer printouts from the Flight Data Recorder had been deciphered, and the voices of men now two months dead had been resurrected from the recording tapes. The evidence was abundant, and allowed investigators to develop a clear picture of what happened.
(Left: NTSB Map of the flight path of Flight 401)
The flight had been normal until the final approach into Miami. When Stockstill had looked at the landing gear indicator, the green light that identifies that the gear is properly locked in the 'down' position didn't illuminate. This failure has two possible explanations: either the gear wasn't down, or the light wasn't working. The pilots recycled the gear. When the light still did not come on, they aborted the landing to examine the situation. The tower instructed the L-1011 to pull out of its decent, climb to two thousand feet, and then make a U-turn and flight west over the darkness of the Everglades. The cockpit crew removed the light assembly and the flight engineer was dispatched into the hell hole to visually check if the gear was down.
Fifty seconds after reaching their assigned altitude and when the plane was halfway through its U-turn, the captain instructed Stockstill to put the L-1011 on autopilot. For the next eighty seconds the plane maintained level flight. Then it dropped one hundred feet, and then again flew level for two more minutes, after which it began a descent so gradual it could not be perceived by the crew. In the next seventy seconds, the plane lost only 250 feet, but this was enough to trigger the altitude warning "C-chord" chime, which is clearly heard on the CVR tapes. During the NTSB hearings, one Eastern captain testified that modern aircraft like the L-1011 have so many "clickers and clackers and bells," that the environment becomes filled with alert tones. "There should only be a warning when a warning need be, not when everything is ok," he noted. So it is possible that the soft, short audio alert went unnoticed in the din of cockpit noise. For whatever reason, there was no indication on Flight 401'a CVR recording that pilots heard the chime.
Meanwhile, the crew continued to attempt to reinstall the light assembly, which had become stuck in the panel ninety degrees clockwise, and would not come back out. During the NTSB hearings, an Eastern L-1011 captain noted that after the accident he and a mechanic tried to remove and replace the gear lamp only to find that, although it is square in shape, it has a small track and groove which only line up when the lamp is positioned correctly. He testified that the track starts about 50% of the way in, so if you start to push it in incorrectly, you don't realize it until the fixture is halfway in its housing and, by then, possibly jammed.
When Miami controller Charles H. Johnson, 40, inquired "how are things coming along out there," Eastern 401 was far below its assigned 2,000 foot altitude. The controller's handling of Eastern 401's go-around came under scrutiny at the NTSB hearings.
At the NTSB public hearings in March 1973, Mr. Johnson (photo: left) was asked why he didn't warn EAL 401 of its low altitude when he first noticed the 900 foot reading on his radar screen. Mr. Johnson testified that he wanted to see another sweep of the radar before making any judgements, that the readouts often differed from the actual altitude. "It's like when your TV picture rolls onece, you don't unplug it and take it to the TV man. You wait for a pattern of operation." He went on to say that in his opinion, the pilots appeared to be in command of the flight, as evidenced by their calm demeanor and rapid response to his instructions and questions. "There was no indication that the crew was unaware of its altitude," Johnson testified. This statement drew attention from an examiner who asked, "how would they indicate that they weren't aware of their altitude?" Johnson stammered for a moment and then sheepishly said, "I don't know."
Johnson's supervisor, Carl E. Joritz, Chief of the Miami Air Traffic Control Center, later pointed out that it is not the controller's duty to monitor the distance between the airplane and the ground, but rather the distance between airplanes. Although technically true at the time, the supervisor admitted that all controllers have a moral obligation to alert flight crews of an emergency situation. When Johnson was asked if he was treating Flight 401 as if it were an emergency situation, Johnson replied, "no." Joritz also testified that pilot groups have asked controllers not to bother them if they are having trouble landing.
(Ironically, on June 21, 1973, Charles Johnson was on duty in the Miami tower when a small plane crashed in the Everglades after having its radio tuned to the wrong frequency. Strangely, killed onboard the small plane was William Gregg, who was onboard another small plane December 29th and had reported seeing Flight 401 crash to the Miami tower.)
Both passengers and crew alike referred to the flight as being normal. "Routine," was a term often used. Flight Attendant Beverly Raposa (seen here in testifying at the hearing in the photo below), recalled that after the decent into Miami International had been aborted, the go-around flight was smooth, with no indication of there being anything wrong until impact.
So, why did the aircraft fall into the swamp that night?
The answer came in fragments. First, Eastern captain Daniel Gellert testified to the NTSB on February 6th that he had noticed that the altitude hold function could be disengaged by bumping the control column. Many pilots doubted Gellert's testimony, but the incident was strikingly similar to a situation encountered by Thomas Oakes, another Eastern pilot. Oakes had been one of the first captains qualified to fly the L-1011. He had the altitude hold function disengage on a flight on January 8th, ten days after the crash of flight 401. Oakes testified that he and the co-pilot noticed the malfunction and proceeded to reset the autopilot and then trip it off by bumping the control column several times. They noted this behavior in their log book. Although these seemed to be freak occurrences, Eastern took it seriously to send a printed notice to all it's L-1011 pilots on January 15th.
(As a side note, on April 8, 1983, Daniel Gellert appeared on NBC Television's Today show. On the show, Gellert discusses his decision to report the L-1011 altitude hold malfunction to the NTSB. Gellert explains that after discovering the problem he went to Eastern management and had a meeting with an airline VP regarding this issue. He claims that the problem went uncorrected. He points out that when Flight 401 crashed into the Everglades because of an altitude hold malfunction, he decided to go to the NTSB. He adds that shortly afterwards he was grounded and ordered to undergo psychological testing. Gellert maintains that he is a competent pilot who has a responsibility to his passengers and believes Eastern had given him a lot of flack and ruined his personal life. Gellert had apparently sued Eastern Airlines for liable around the same time as the NBC interview. In Eastern Air Lines, Inc. v. Gellert, 438 So. 2d 923 (Fla. 3d DCA 1983), the Third District Court of Appeal analyzed whether Eastern Air Lines was liable for defamatory statements madeto the press by the director of Eastern Air Lines' news bureau. The court held that Eastern Airlines could not liable for punitive damages absent proof that it was independently at fault).
Given this information, the NTSB hypothesized that Loft had probably bumped the control column when he turned to tell flight engineer Repo to "get down there and see if that goddamn nose wheel's down." The NTSB report continued: "If the captain had applied a force to the control wheel while turning to talk to the second officer, the altitude hold function might have been accidentally disengaged." The autopilot had apparently not turned off completely, but rather had switched into the "Control Wheel Steering" mode. The Whisperliner was no longer locked at two thousand feet, but would fly steadily at whatever level the pilots selected, purposefully or accidentally, by pressure on their control wheels. From this point on, even a slight nudge would be enough to edge the plane up or down.
An adjunct mystery which never really was solved was whether the altitude hold light extinguished when the function disengaged. In both Gellert's and Oakes' cases, they noted the autopilot light went out when they bumped the columns. But Stockstill might have been deceived by the mismatched autopilot computers on N310EA. There are two autopilot systems, an "A" and a "B." Because the computers were mismatched, Loft's side required 15 pounds of pressure to disengage, and Stockstill's side required 20 pounds of pressure. Had Loft bumped the column with more than 15, but less than 20 pounds of pressure, Loft's altitude hold light would have gone out, and Stockstill's light would remain on, giving him the erroneous impression that the autopilot was still engaged and holding the plane at two thousand feet. This could be the case, however, only if Stockstill had selected the "A" computer, which would be unlikely as the switch for the "A" computer is on Loft's side of the control panel. Either way, the NTSB did not believe that this was a critical factor in the accident.
One hundred and three people died. The fifteen million dollar aircraft was destroyed. And it al began with two burned out light bulbs with a replacement value of twelve dollars.
The landing gear was found to be in the down and locked position.
The report cited the cause of the crash as pilot error, specifically: "the failure of the flight crew to monitor the flight instruments during the final four minutes of flight, and to detect an unexpected descent soon enough to prevent impact with the ground. Preoccupation with a malfunction of the nose landing gear position indicating system distracted the crew's attention from the instruments and allowed the descent to go unnoticed."
In May, 1973, the NTSB made two recommendations regarding the design of the L-1011. First, that a light switch should be installed near the observation window in the avionics bay, and that the altitude alert light on Eastern's versions of the TriStar be modified so that they blink continuously when the jet deviates from the assigned altitude by more than 250 feet.
Especially if it doesn't have anything to do with you personally.
