Post on 15-Jul-2015
Lockheed L-1011-1 Tristar
11:42pm December 29, 1972
Flight 401
Sajid Nadeem - 12002001004
Summary
101 fatalities (99 initial crash fatalities, two died shortly afterward)
75 survivors
Crash reason: entire flight crew becoming preoccupied with a burnt-
out landing gear indicator light and failing to notice the autopilot had
been disconnected. As a result, the aircraft gradually lost altitude and
eventually crashed while the flight crew was distracted with the
indicator problem. It was the first crash of a wide-body aircraft and at
the time
Four-month-old aircraft - the pride of Eastern's fleet
163 passengers and 13 crew members (10 female flight attendants)
This re-enactment was filmed in a simulator, and was not produced by Eastern Airlines.
In this video, following the unintended departure from 2000 feet, a warning tone is heard, and footage of the altimeter shows a continuously flashing amber light. Eastern Airlines had repressed the flashing alert light below 2500 feet above the ground, so on the accident airplane, only the tone was produced, at 1750 feet. There would have been no flashing light.
This discrepancy in the video could lead the viewer to assume that the flight crew must have ignored, or missed, two warnings, while in reality, the only warning that would have existed would have been a single, short duration, aural tone
According to the FAA
What in your opinion is the category of this crash?
Question From Audience
• Over reliance on Automation
• CFIT
Answer:
Captain Robert Albin 'Bob' Loft, 55, a veteran EAL pilot ranked 50th in seniority at Eastern (from 4000 pilots). Captain Loft had been with the airline for 32 years and had accumulated a total 29,700 flight hours throughout his flying career.
280 hours in the L-1011
Pilot In Command
Albert John Stockstill, 39, had 5,800 hours of flying experience
Second Officer (flight engineer) Donald Louis 'Don' Repo, 51, had 15,700 hours of flying experience.
First Officer and Flight Engnr.
Warren Terry, a co-pilot, and Angelo Donadeo, a maintenance specialist. Both of whom were off duty airline employees who were "dead-heading" - airline slang for employees hitching a free ride to return from a duty assignment.
Extras On-board In Jump Seats
The crew of Flight 401, taken aboard Flight 26 while on the ground in
Miami earlier the day of the crash.
Because it was the end of the month the crew
would be breaking up soon. "This is going to be
our last trip together,"
The Whole Story
The flight was routine until 11:32 p.m. when the flight began its approach
into Miami International Airport.
After lowering the gear, first officer noticed that the landing gear
indicator, a green light identifying that the nose gear is properly locked in
the "down" position, did not illuminate. The landing gear could have
been manually lowered either way. The pilots cycled the landing gear
but still failed to get the confirmation light.
By "down there," CAPT was referring to the forward avionics bay, a space
beneath the flight deck more commonly called the "hell hole." The bay was
accessible through a small square trap door on the floor of the cockpit.
Inside the hell hole was an optical sighting device which could be used to
view the landing gear itself.
The Investigation
The investigation focused primarily on determining why the unexpected
descent had occurred.
The NTSB considered four possible causes:
• Subtle incapacitation of the pilot
• Auto flight system operation
• Flight crew training
• Flight crew distractions
Medicals
The Crew And The Aircraft
CVR and CDR found intact
So Why Did This Happen?
Pilot`s Medical Ruled Out
Is Training Adequate?
Automation ?
Air Traffic Controller ?At the NTSB public hearings in March 1973, Mr. Johnson (ATC) 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.
He went on to say that in his opinion, the pilots appeared to be in
command of the flight, as evidenced by their calm demeanour and rapid
response to his instructions and questions.
Johnson's supervisor, Carl E. Joritz, Chief of the Miami ATC 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. This was technically true at the time.
The Crash Summary
Investigators discovered that apart from one burned out bulb, there was nothing wrong with the L-1011.
The main causal factor in this accident was not the aircraft, but the crew, the human factor.
Cognitive Tunnelling
Even though the crew was dealing with the landing gear indicator, they still could have
noticed their surroundings and the aircraft's altitude.
As long as stress levels are not too high, the average human has enough additional
information processing capacity to notice things unrelated to the current task, such as the aural altitude warning, and instruments indicating a descent (Robson, 20082). When stress
levels increase, however, it is possible for cognitive tunnelling to develop (Chou, Madhavan,
& Funk, 19963); this is where one particular task is given a very high priority at the expense of
other tasks. It can be especially dangerous when the task being focused on is actually less
important than those tasks being neglected. Initially, it may seem that the crew was
presented with the simple task of changing a light bulb. However, as the cover had
jammed, both the captain and first officer likely experienced cognitive tunnelling as they tried to establish a way of replacing the bulb without breaking the cover. In this case, all of
their attention was given to this one small problem, at the expense of flying the aircraft.
Lack of CRM
The fact that all three crew members were dealing with the problem in the first
place was an extreme command/control failure. (Poor Delegation of tasks)
The most basic level of command/control is crew coordination, ensuring that
individual tasks, such as replacing the bulb, and flying the plane, are effectively
divided between crew members so that the main overall objective, in this case
landing the aircraft safely, can be successfully accomplished (Kanki & Palmer,
19934). This was a deficiency on behalf of the captain to either delegate or
take control of the landing gear, and have at least one pilot in charge of flying
the plane.
At the time, CRM was not a developed system and so the crew did not have
the opportunity of developing the same effective team-work skills as modern
pilots.
Steps Eastern Took:
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 behaviour 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.
The information that “bumping” into the control column on a Tri-Star could disengage autopilot was put-up on the notice board and mailed to all
L-1011 pilots.
What did NTSB do?
Introduce new regulations to prevent such future accidents
ATCs now had the duty to contact the A/Cs when they are too near the ground
Still, CRM was not introduced. & years later, Tenerife 1977 accident occurred. NASA started to work on it after that.
Any Questions?