Trident Crashes in Britain's Worst Aviation Accident
By Patrick Mondout
On June 18, 1972, British European Airways (BEA) Trident-1C operating
as Flight BE548 with 109 passengers and nine crew left London's Heathrow
Airport for Brussels. It crashed some 2 1/2 minutes later into a field
near Staines - just missing the A30 motorway - killing everyone on board
(one unconscious passenger was rushed to the hospital but died). To this
point in history, it was Britain's worst aviation accident.
The Hawker Siddeley Trident aircraft included a unique feature called
droops. These were used to additional lift while a plane is taking off.
Noise restrictions at Heathrow required the aircraft reduce thrust to the
engines 90 seconds after starting the takeoff roll. With a Trident
and these restrictions, the droops were a must in order to fly.
Nearly two minutes into the flight, at about 1700 feet of altitude, and
- critically - at 170 knots per hour, the droops (which control the wing
leading edge slats) were retracted. The droops should have remained
extended for another two minutes and certainly not retracted until a speed
of 220 was reached.
The experienced 51-year-old Captain Key certainly knew better than to
retract the slats at this stage of the flight. Investigators later proved
that it was intentional and not a mechanical problem with the equipment
involved. So why did he do it? And why didn't Second Officer Keighley or
S/O Ticehurst override the captain's fatal decision?
Without a cockpit voice recorder (CVR), which were not required in
Britain at the time, we will never know for sure. The Air Accidents
Investigation Board (AAIB) concluded that Keighley was too inexperienced
and that Ticehurst was preoccupied with the passenger in the cockpit
(another BEA captain on a return flight).
A British Trident 1 similar
to flight BE548 as seen at Heathrow in September
Image courtesy of AirNikon.
Find more of his photos at Airliners.net
Two seconds after the droops were retracted, the stick-pusher stall
recovery device operated, causing the autopilot to automatically disengage
and the nose of the aircraft to pitch down. At that moment, the stall
recovery system was manually inhibited by one of the pilots. The aircraft
then pitched up rapidly, losing speed and height, entering a true
aerodynamic stall and then a deep stall from which no recovery was
possible. Impact occurred 20 seconds later.
Although it is possible that this crew might have overcome the droops
mistake with the full thrust used at airports that do not require this
procedure, the Air Accidents Investigation Branch (AAIB) concluded:
"The noise-abatement procedure did affect [the Trident], in that
the reduction in thrust was one of the causes of the loss of speed. In
one sense any procedure which demands that an aircraft should fly at
less than its optimum power for that stage of flight is undesirable.
However, aeronautical and social considerations have to be blended as
best as possible."
Did the Captain have a Heart Attack?
Because the bodies were not burned, it was possible to conduct
autopsies. An autopsy on the captain he had probably had a heart attack
during the short flight. As there was no CVR we will never know what
effect this might have had on the flight. Did he engage the droops while
preoccupied with sharp pains or with a diminished mental capacity? Were
the others preoccupied with the health of their captain at the critical
Violent Argument Before Flight
A factor that may have led to an uncooperative cockpit was labor
unrest. There had been a dispute between BEA and its pilots were divided
as to whether or not to strike. There was incident involving the captain
shortly before the flight as related in the AAIB report:
"About an hour and a half before the departure of Papa India,
Captain Key was in the crew-room. Also there was a large number of other
pilots, amongst them F/O Flavell. It seems that Captain Key, who was, as
will already have been gathered, opposed to pilots taking strike action
in support of their claim for higher salaries, had been enlisting the
support of some of his fellow Senior Captains. F/O Flavell asked Captain
Key how these efforts were progressing. This question provoked an
outburst from Captain Key, who told F/O Flavell that the matter was just
as confidential as the BALPA ballot. This outburst was described by at
least one eye-witness as the most violent argument he had ever heard,
although it seems to have been less of an argument than a one-sided
expression of views. Whichever it was, although Captain Key was plainly
very angry indeed, it subsided as quickly as it had erupted and the
Captain took F/O Flavell by the arm and apologized for what he had said.
Thereafter he seemed to outward appearances to be his normal self.
Suggestions were made by Mr Kreindler in argument that this outburst
provided evidence that Captain Key was psychologically unfit to fly, and
that some unspecified method should have been provided to ensure that he
The AAIB concluded the immediate causes of the accident were:
- A failure by Captain Key to achieve and maintain adequate speed
after noise-abatement procedures.
- Retraction of the droops at some 60 knots below the proper speed
causing the aircraft to enter the stall regime and the stick-shaker
and pusher to operate.
- Failure by the crew to monitor the speed errors and to observe the
movement of the droop lever.
- Failure by the crew to diagnose the reason for the stick-pusher
operation and the concomitant warnings.
- The dumping by the crew of the stall recovery system.
Cockpit Trident Cockpit
|Courtesy of the
The AAIB also concluded the underlying causes were:
- The abnormal heart condition of Captain Key leading to lack of
concentration and impaired judgment sufficient to account for his
toleration of the speed errors and to his retraction of, or order to
retract, the droops in mistake for the flaps.
- Some distraction, the nature of which is uncertain, possibly due to
the presence of Captain Collins as a passenger on the flight deck,
which caused S/O Ticehurst's attention to wander from his monitoring
- Lack of training directed at the possibility of 'subtle' pilot
- Lack of experience in S/O Keighley.
- Lack of knowledge in the crew of the possibility or implications of
a change of configuration stall.
- Lack of knowledge on the part of the crew that a stick-shake and
push might be experienced almost simultaneously and of the probable
cause of such an event.
- Lack of any mechanism to prevent retraction of the droops at too low
a speed after flap-retraction.
Source: AAIB report.
|British European Airways (BEA) 548 at a Glance|
|Airline||British European Airways (BEA)|
|Date||June 18, 1972|
|Crew Fatalities||9 of 9|
|Passenger Fatalities||109 of 109|
|Total Fatalities||118 of 118|
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a Wing and a Prayer: Interviews with Airline Disaster Survivors.
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Aviation Safety, 3rd Edition. McGraw-Hill Professional, 2001.
Share Your Memories!
What do you remember about this crash? Were you a witness? Have you any compelling stories to share? Share your stories with the world! (We print the best stories right here!)
Your Memories Shared!
"I was a postgraduate sociology student at the L.S.E. studying airline crew industrial relations at the time of the accident. I had begun to accumulate substantial evidence of severely disturbed and disharmonious relations between flight crew as a normal part of aviation at that time.
When a plane took off, an international flight crew might have a pilot in BALPA, a navigator in the MNAOA, an engineer in his association and cabin staff in at least two warring unions representing male staff on long term contracts and the other, representing female staff who were obliged to retire once wrinkles set about the age of 30.
Arguements were common on board, trade unionised staff wouldn't speak to the other at times and all that took place during an industrial dispute with weak management (claimed the flight staff). Not a happy situation for either passengers and crew.
Things have changed a lot since then, I'm very glad to say. As a result of the Staines disaster, all external observers were unofficially barred from contact with flight crew from BEA/BOAC. That ended my M.Sc. studies in the area - as a very trivial side effect of the disaster. I was all too glad I was able to walk away with my life ahead of me, while the participants of the disaster did not."
--paul.millar at ntlworld dotcom
"I have just been reading the reports of the Trident Crash at Staines.
I flew as a Stewardess on Papa India many times, and also with Captain Key.
There were many crew members with BEA so it was hard to remember them individually, because we generally flew with different people every day.
However, Captain Key was very memorable, as he was not a very
pleasant or friendly captain to fly with, he was always the same. Most second officers are very young and probably did not have enough experience of courage to contradict someone like Captain Key, in fact I don't know anyone who contradicted him.
I had the impression he was not a very happy person. Certainly he was not a Captain one would choose to fly with. In fact I cannot think of a more unpleasant person any crew member would wish to fly with. I think it was probably the norm for him to be unfriendly with his own cockpit crew, as well as the cabin crew.
If he did have a medical problem which caused him psychological problems, I would think it probably had it for a long time, or else he had severe problems somewhere else in his life. Most airline crew are very laid back and friendly.
Hope this is of interest to you. [Editor's note: It is. Thank you.]"
--Linda Coyle (BEA 1966 - 1972)
"I was 14 at the time of this crash. My father worked on the engineering side for BEA and although we lived in Yateley at the time all my relatives lived in London.
I remember passing the crash site very soon after the crash on our way to visit relatives in SE4 and it looked so obscene and frightening just lying in the field by the side of the A30.
I think my father was quite upset by it although he didn't say much."
"My uncle was a fireman at the time of this and did attend the crash.The captains body was removed from the front of the pax cabin and not on the flight deck!
Also what would "human factors" say today about capt Keys and his man management skills!"
"I was also 14 yrs old at the time and was playing near a restauraunt called the Crooked Billet and saw the aircraft come down. Since then I flew on the Trident many times and it was a great aircraft."
"I was seven at the time of the Trident crash at Staines and was in my parents car returning from London. We got stuck in the traffic jam around 5. 30 and in those days we did not have a radio in the car so were initially ignorant of the crash, we assumed there had been a motor accident. We soon learnt from other drivers that it was a plane crash, so my father did a U turn and made another way home. My uncle worked for BEA Cargo at the time and new Captain John Collins who was on the jump seat of the Trident directly behind Captain Key as he was flying out to Brussels to collect a BEA Vanguard freighter. He boarded the Trident at the last minute. Captain Collins lived in my home town Woking.
The Staines crash never left my mind and since then have always remembered it every June 18th as this is my wife's birthday too! I pass the crash site reqularly and wish that there was a memorial erected to this accident which made Cockpit Voice Recorders (CVR's) mandatory in all British airliners and remains to this day Britains worst air accident."
A number of BEA Trident 3s at Heathrow, September 1978.
Image courtesy of AirNikon. Find more of his photos at Airliners.net
Airline: British European Airways (BEA)
Location: near Stains, England
Aircraft: Hawker Siddeley HS-121 Trident 1C
Date: June 18, 1972
Total Fatalities: 118 of 118