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On 22 August 1985, an engine of British Airtours Flight 28M fails during takeoff, puncturing a hole in the wing fuel tank and starting a fire. The crew successfully abandons the takeoff and stops the aircraft on the runway, but the fire spreads to the cabin. Out of the 137 occupants onboard the flight, 55 people die before they can evacuate, mainly due to inhaling toxic smoke. The investigation found that a defective engine fuel injector failed and ruptured the fuel tank.
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00:01VTOL 28, you are clear for takeoff.
00:1480 knots.
00:19Stop!
00:20Don't hammer the brakes. Don't hammer the brakes.
00:24137 people are on board this British Air Tours flight.
00:27Within minutes, nearly half of them will be dead.
00:30This should not really have happened.
00:33Evacuate! Evacuate!
00:34The aircraft didn't even get airborne.
00:37It didn't run off the runway, and yet still 55 people were killed.
00:41For investigators, it's a familiar routine.
00:45Reconstructing the final moments inside the cabin.
00:48Analyzing the wreckage and the flight data recorders.
00:52In the end, they turn to a psychologist to help them figure out
00:55how a survivable emergency turned into one of British aviation's
00:58most horrific disasters.
01:03They turn to a patient in the air in the air.
01:07They turn to the space and suddenly they turn around.
01:12Take this!
01:13We are ready.
01:14We are ready.
01:17We're ready.
01:18We're ready.
01:25We're ready.
01:28We're ready.
01:30six in the morning on august the 22nd 1985 manchester's airport is coming to
01:37life the first flights of the day are being prepped for departure
01:46British Air Tours flight 28 is scheduled to take 131 passengers from Manchester
01:51to the Greek island of Corfu British Air Tours is a division of British Airways specializing in
02:01low-cost flights to vacation destinations it's a chilly morning a slight breeze is blowing ideal
02:11flying weather most of the passengers on this early morning flight are traveling on vacation
02:27Lindsay Davis is heading to Greece with her boyfriend Charlie thixon we've been going out
02:34with each other for a year and that's one of the reasons we were so excited about it you know
02:40it
02:40was our first holiday together captain Peter Tarrington is in command I was the senior training
02:49captain on the fleet first officer Brian love is being trained by Tarrington he was going to
02:55perform the takeoff and landing as part of his training all right captain yep briefing and Brian
03:04airfield emergencies you handling the aircraft what are the four things you're gonna stop for fire
03:09failure configuration warning or you're shutting stop okay so you bring that thing to a stop and I'll
03:15take over the aircraft and leave you to deal with emergency I'll liaison ATC okay if you've talked
03:21about the possibility of emergency and talked over what you will do then if it actually happens it's easier
03:28to recall those items okay Brian start to starting to well pressure rising okay go on five and six 27
03:4228 29
03:46129 plus two on board captain all strapped indoors or closed down automatic thank you Arthur the crew is flying
03:54a Boeing 737
04:06it takes just four minutes for the plane to reach the foot of the runway
04:12V tours 28 you are clear for takeoff the 737 has 3000 meters to get to takeoff speed
04:22the engines are pushed to high power
04:28I was sitting by the window looking out of the window everything was normal the plane was going
04:33quite fast 80 knots check
04:53I was really keen to see what was going on outside but couldn't see anything captain
04:59Tarrington needs to act fast
05:01stop
05:10and immediate reaction was to stop we were quite a few knots below our decision speed so I very quickly
05:19closed the throttles and applied reverse thrust
05:22we could feel the aircraft slowing down and I said I think we've blown a tire and I didn't know
05:29so we just
05:31waited to hear it
05:35don't hammer the brakes don't hammer the brakes
05:42I thought the tire might have gone and would cause damage the undercarriage if we break too strongly
05:50probably nothing I wouldn't worry
05:53I just assumed that maybe a tire had burst so I wasn't really alarmed at that point
05:57my thought at that time was okay we're going to get off this plane and probably have to move all
06:03the
06:03luggage onto another plane and and take off
06:11soon passengers on the left side of the plane see the real problem
06:19I could see orange flames inside the back of the engine and at that point I thought it's obviously not
06:27a burst tire that wouldn't cause that and this is perhaps something a bit more serious
06:34let me buy
06:36I'm not staying there
06:37but at that point I knew that I wanted to get off the plane and and I wasn't happy at
06:42all
06:44I knew that there was a fire and I just wanted to get away from the fire
06:48smoke is seeping into the cabin
06:51please sit down
06:52my nearest exit was at the back
06:54I didn't want to go to the back because the smoke was coming in there
06:57so I decided in my mind that I was going to go through the front
07:01I said to Charlie
07:02come on we're going
07:03and that's when I started going towards the front of the plane
07:09stop it
07:1028 Mike we're abandoning takeoff
07:14that's why we've got the fire on number one
07:19looks like there's a lot of fire
07:20thank you
07:22plane on fire runway 24
07:24from where he's sitting Captain Tarrington can't see how bad the fire is
07:29he needs advice from the tower
07:30do we have to get the passengers off
07:33I would do by the starboard side
07:36Tarrington decides to pull off the runway
07:41evacuate to the starboard side please
07:57before the flight crew leaves the cockpit they must complete a 15 step checklist
08:04parking brake set
08:06speed brake lever
08:07down
08:09but time is running out
08:11we had an evacuation checklist but it was four pages long and the last item was to get the passengers
08:17off
08:18engine and APU fire warning switches
08:20this didn't cover my problem at all
08:23on the 737 there are four cabin doors
08:27the two in the back are covered in flames and smoke leaving only two for 137 people
08:37then a mechanical problem eliminates one of those
08:53the back of the cabin is filling with smoke it's making breathing difficult passengers rush it just seemed to go
09:05on forever before they started evacuating
09:08and that's when I thought I'm not going to get off it's going to blow up with all of us
09:13on it
09:14engine and APU fire warning switches
09:17right now all 137 people on board are alive
09:21but with every second their odds of surviving are decreasing
09:27flight 28 is becoming a death trap
09:42the jammed door on the right side of british air tours flight 28 leaves the crew no choice
09:50they must get the passengers out from the side of the plane that's burning
09:59since we opened the door the fire service were already around shooting foam up the slide and came into the
10:06galley floor
10:10we wanted to start to accurate the passengers but there's a bit of a bottleneck and nobody was coming forward
10:15the aisle is quite narrow where the galley is and they were sort of pushing forward and I could see
10:22this boy
10:23that was really sort of pushed against the wall
10:30he couldn't get out so I pulled him by his t-shirt had the yellow t-shirt on and he
10:35he sort of tumbled forward and after that everybody sort of just tumbled in behind him
10:41and we just direct them down the slide
10:46jump, jump, jump
10:49in training they tell you to bring people to the door and you tell them to jump
10:58desperate to get people off the plane quickly
11:01the purser returns to the jammed door
11:04after several attempts he manages to force it open
11:09the only time I turned around was to make sure that Charlie was following me
11:15see you out there
11:18one thing I did see when I looked back was people
11:22going to the front towards the front of the plane
11:24where the seats are and pushing the seats forward folding them down
11:28as they went along so people were trying to rush forward from the back
11:33the chute was open and people were just jumping up straight onto the chute
11:39as I got to the bottom didn't look back at all
11:42I was just wanting to get off
11:44dozens of passengers have made it off the plane
11:47but there are still many more inside
11:50but it was smouldering and it was black, thick black smoke
11:54and Charlie had said that after you'd gone
11:56this black smoke came down
11:59he said and everybody was screaming and panicking
12:05he said people are going to die in there
12:08standby power switch
12:10Captain Peter Terrington and his first officer Brian Love
12:13are still aboard the burning airplane
12:15and they still haven't completed the steps required to evacuate
12:22there was four tons of fuel coming out of that aircraft wing tank
12:26here go Brian, go Brian
12:28I could see quite a lot of flames
12:32completing the checklist would put their lives at risk
12:37we did as many items as we could
12:40and then we both went out of the flight deck window
12:50there are no more passengers at the exits
12:53so Joanna Toff decides to see if anyone else is left in the cabin
12:58the smoke was... you could touch it, it was so thick
13:02and you could take... it was awful really
13:04let's go
13:19there was a young girl
13:20just a bit further down in the cabin
13:23but she was really disorientated
13:25I mean I suppose we all were really
13:27we just didn't have any idea what was going on
13:32I just brought her down to the slide
13:33she was taken off then
13:37the fireman was telling me to come on
13:40and I...
13:40and I was thinking
13:41well...
13:42I'm not finished
13:43you know, we've not finished yet
13:47when Toff re-enters the cabin
13:49the thick smoke makes it as hard to see as it is to breathe
13:55it was really dark and quiet
13:57I've never seen anything like it
13:58and I could see the light from the door anyway
14:00by then
14:01so I knew where the door was
14:03the smoke forces Toff to abandon her search
14:14just minutes after pulling off the runway
14:17British Air Tours Flight 28 has been consumed by fire
14:21we got out of a flight deck which was relatively intact
14:26and when we turned round on the ground
14:29we saw a complete wreck of an aircraft
14:33and it had happened in a matter of seconds
14:37it was...
14:39uh... dreadful
14:4454 people are dead
14:47another would die in hospital
15:01there was nothing wrong really with us
15:03we thought nothing physical wrong with us
15:05but our lives changed
15:07you know, just in those... in those few hours
15:21I couldn't breathe
15:23I was virtually out the door
15:24I couldn't breathe there
15:25the smoke was coming in
15:27and everybody just stood up and...
15:30ran out
15:31it was just a mad panic getting out
15:33because when the smoke came
15:34you just couldn't see anything at all
15:36you couldn't see anybody
15:39it takes 125 firefighters
15:42more than two hours to put out the fire
15:48news of the disaster soon spreads around the world
15:51British Prime Minister Margaret Thatcher
15:54flies to Manchester to visit the scene
15:57when we get a terrible air crash of this kind
16:00everyone is appalled and shocked
16:02every single aspect of this accident
16:05will be thoroughly investigated
16:07it has to be
16:09this is the fourth major commercial air disaster of the year
16:13in June of 1985
16:15an Air India jet exploded over the Atlantic Ocean
16:22329 people were killed
16:24weeks later
16:26137 people died
16:28when a Delta Airlines flight
16:29crashed at Dallas Fort Worth Airport
16:34and just 10 days before the Manchester crash
16:37the deadliest single aircraft accident in history
16:41Japan Airlines flight 123
16:43a fully loaded 747
16:45slammed into a mountain
16:47killing 520 people
16:55British Air Tours flight 28
16:56adds 55 new victims to the list of casualties
17:001985 is now the deadliest year
17:02in the history of commercial aviation
17:05the flying public is getting nervous
17:12Britain's air accidents investigation branch
17:15sends a team to Manchester
17:16to unravel the events that led to the catastrophe
17:20among them Steven Moss
17:22he'll be inspecting the plane's engines
17:26this should not really have happened
17:28the aircraft didn't even get airborne
17:30it didn't run off the runway
17:32and yet still 55 people were killed
17:35Chris Prothero is also on the team
17:39his focus is on the fire
17:44we were aware from initial reports
17:47that the fire had entered the
17:49the aircraft very rapidly
17:51as the aircraft came to a halt
17:52and that that was a focus for me
17:57it doesn't take too long for Steven Moss
17:59to figure out where the trouble started
18:03he sees damage to the plane that was not caused by fire
18:08well the first thing we noticed clearly was the hole in the underside of the wing
18:16and right next to it was a gaping hole in the side of the engine
18:19seems that one had led to the other
18:30to get a plane loaded with passengers off the ground
18:33you need to generate massive thrust
18:37that power is created when air travels through the front of the engine to a series of compressor fans
18:43it's then ignited and the exhaust pushes the plane forward
18:50something had clearly gone very wrong with flight 28's left engine
19:01investigators look for clues on the runway and in the cabin
19:05hoping to discover why so many people died
19:14entering the cabin for the first time there was a
19:18as with all aircraft fires there's an overwhelming pungent smell
19:23burning plastic burnt fuel burning material that had dropped down onto seats
19:29and so the aisles were filled up with the remains of overhead lockers
19:36a scene of devastation
19:41the damage in the cabin is revealing
19:44it's almost completely charred up high
19:48but it's relatively intact down low
19:52it was clear that they had not been a flashover in this particular case
19:58a flashover occurs when the gases in an enclosed space become so hot that they ignite incinerating everything around them
20:11the way flight 28's cabin is charred tells Prothero about the nature of the fire
20:18many of the seat squab cushions even things like the emergency evacuation cards which is just plastic laminated
20:27cards were pretty much undamaged
20:30you could have wiped them off and put them on another aircraft and nobody would have known they'd been in
20:34this accident
20:34whereas at the upper levels in the fuselage there was a great deal of heat damage
20:39and this is not a characteristic of a flashover
20:45the fire in the cabin had been severe but should not have been catastrophic
20:51this leaves investigators with two questions
20:53why did so many people die?
20:57and what caused the fire?
21:03the answer to the second question may be outside the plane lying on the runway
21:09investigators find a large piece of dome shaped metal along the plane's path
21:17Stephen Moss can see it's from a piece of the engine called a combustor can
21:26it looks like there's been a separation of the can from the front end from the back end
21:32the combustion chamber of the 737's jet engines contains nine combustor cans
21:38it's where fuel and air are mixed and ignited
21:41so each can needs to withstand intense heat
21:48Moss suspects the fractured can somehow blew apart and destroyed the plane's left engine
21:54it had struck an underwing fuel tank access panel
21:57and put a sizeable hole in that
22:00which directly led to the release of a vast quantity of fuel
22:05proving the piece of the combustion can penetrated the wing is easy
22:10it fits neatly into the hole in the wing
22:13this was clearly, if you like, the root cause of the accident
22:17the engine on the plane is a Pratt & Whitney JT-8D
22:21for Moss that's of grave concern
22:24at the time was probably the most widely used jet engine on commercial air transport in the world
22:31and it was obviously pretty urgent that we try and find the cause of this one
22:37in order to prevent other aircraft having the same problem
22:42there are tens of thousands of combustor cans in service around the world
22:47one of them erupted in Manchester
22:53Stephen Moss needs to find out why it failed
22:57and fast
23:06investigators looking into the deadly fire on board British Air Tours Flight 28
23:11study the plane's maintenance log
23:13they discover the combustor can that ruptured had previously been repaired
23:20we needed to look at that repair and how effective it was
23:27during a routine inspection a year and a half earlier
23:31mechanics had found small cracks in some of the combustor cans
23:43it was certainly not uncommon to find fatigue cracks in the cans
23:51they're operating in a high temperature environment
23:55the manuals give various schemes for repairing these cracks
24:00investigators find mechanics repaired the cracks according to a procedure
24:05they were laid out in the engine repair manual
24:07they welded them closed
24:09but the crack on can number 9 was unusually long
24:15the overhaul manual did not give any limit on the length of crack that could be repaired
24:21and it was a longer crack than had been experienced before
24:25it was still repaired
24:29after the repaired cans were put back in the engine
24:32mechanics had no way of knowing the weld didn't effectively seal the crack
24:39that's because the cans can't be inspected while the engine is on the plane
24:45since the repair there were 11 reports of slow acceleration from the engine that exploded in Manchester
24:54a damaged combustor can could have been a reason for the problem
24:59but troubleshooting guides available to mechanics in Manchester didn't list that as a potential cause
25:06instead Pratt and Whitney offered other ways to fix the acceleration problem
25:10it didn't seem to ring any great alarm bells with them
25:15if you like it's they'd seen it before
25:18and it had never turned out to be anything serious
25:23so mechanics in Manchester made minor adjustments to fix the plane's idle speed
25:28and kept the plane in operation
25:33cockpit voice recordings reveal that the crew of flight 28 was aware there was a problem with slow acceleration
25:41slow acceleration on number one engine day before yesterday
25:44I was on the flight yes sir
25:45engineer signed off on it
25:47but the log entry led Captain Terrington to believe that the problem had been fixed
25:54a comment in the tech log for the flight before the last one
26:00that the engine was slow and accelerating
26:03it wasn't apparent as a serious problem
26:05because the engineers had done some work
26:07and the aircraft had been flying the previous day with no problems
26:13the idle speed adjustments didn't fix the real problem
26:17the cracked combustor can
26:19and it reached the breaking point on flight 28
26:26stop it
26:2628 Mike we are abandoning takeoff
26:30evacuate evacuate
26:31please stay calm and don't panic
26:36if the airline had inspected the cans
26:39I think there is no doubt that they would have seen the problem
26:46investigators now know the origins of the Manchester disaster
26:51the welded crack in combustor can number nine gave way as flight 28 sped down the runway
26:57the front of the can was ejected from the engine and put a hole in the underside of the left
27:02wing
27:03that led to a huge fuel leak onto the damaged engine which caused the fire
27:09engine fires are not uncommon
27:12the body of a 737 is insulated with fire retardant material to protect the cabin
27:18investigators still don't understand how a fire outside the plane spread into the cabin as quickly as it did
27:25fire inspector Chris Prothero finds part of the answer from viewing photographs of the plane as it sped down the
27:31runway
27:32it was clear from these photographs that there was a very dynamic phase to the fire whilst the aircraft was
27:38at speed on the runway
27:39which produced this energetic turbulent sort of blowtorching type of fire visually anyway trailing behind the aircraft
27:50a press photo from the day of the crash leads Prothero to a new theory
27:55the photographs of the aircraft that appeared in the press showed the left thrust reverser deployed
28:04the general impression that one got visually from that photograph was that the thrust reversers had effectively blowtorched fire against
28:12the side of the fuselage
28:14and that that if you like was the explanation as to why the fire had penetrated so quickly
28:21that photograph and the implications of it actually therefore loomed quite large
28:28stop there are several ways to bring a speeding jetliner to a halt
28:33one is with the brakes
28:34don't hammer the brakes
28:37another is with the engines thrust reversers
28:40thrust reversers redirect the exhaust from the jet engine forwards
28:44this helps slow the plane down
28:47it looked as though the thrust reversers had simply blown
28:52this big fire on the left of the aircraft against us directly onto the side of the aircraft
28:58directly onto the rear fuselage
29:01that would explain why the fire destroyed the cabin so quickly
29:05it now seems possible that Captain Tarrington made the fire worse by trying to slow his plane down
29:12but Prothero has two good reasons to doubt his theory
29:16one is the location where charring from the burning exhaust gas or efflux was found
29:27the efflux impinges on the fuselage further up
29:31closer to the roof the crown skins of the aircraft so actually
29:36the penetration that we had low down did not fit
29:40with that
29:42and the other reason is by the time the thrust reversers were deployed
29:46the left engine had already exploded
29:52but to act as a blowtorch the engine would have needed considerable exhaust
29:59we did calculations to confirm that the residual thrust from that engine
30:04would not have had the energy to have this effect
30:08that confirmed that the thrust reversers couldn't actually
30:11have played any role or significant role anyway in the in the fires severity
30:21clearly something other than the thrusters had caused the fire to spread so quickly
30:25Prothero looks more closely at the data
30:28after examining weather reports from the day of the accident
30:39the wind was the main factor that determined the severity of the fire in terms of its attack on the
30:45outside of the aircraft
30:47how rapidly it penetrated the aircraft and it also affected the conditions inside the cabin
30:53believing he had blown a tire
30:55captain terrington made a fateful decision
30:57stop it 28 mic we are abandoning takeoff
31:00well when that when we when we heard the thud and we we closed the thruffles
31:05it was my assumption that we were going to turn off the runway
31:08clear the runway ask air traffic for an engineer to come out and check the tires
31:12like a highway an airport runway has a series of exits
31:17captain terrington chose one called link delta
31:22we got the fire on number one
31:26when we got the additional information of a fire warning
31:30the brain was already programmed to carry out the stop
31:38the crew had been aware that they had a fire but didn't really appreciate at the time
31:42that the nature of the fire the severity of the fire so they had turned off the runway
31:49captain terrington turned his plane to the right and brought it to a stop
31:54he couldn't have realized that doing so would make the problem far worse
31:59there was a crosswind a slight crosswind from the left side of the aircraft
32:04that was carrying the fire that was burning from the fuel that was pulled underneath the left wing
32:11it carried that fire aft rearwards and took over and under the rear fuselage
32:19in between the wing and the tail plane
32:22the wind wraps the fire around the back of the plane
32:26and into the cabin
32:29if there had been no wind at all I think the situation would have been very much more benign
32:37investigators have discovered how the fire started and the conditions that caused it to penetrate the cabin
32:46now investigator Ed Trimble must solve the biggest mystery surrounding the Manchester accident
32:53here we had an aircraft which had aborted the takeoff for good reason
32:58had taxied off and stopped in a taxiway in an expeditious manner
33:06and yet 55 people had lost their lives so there was a big question as to precisely why that had
33:15occurred
33:19investigators learned that most of the dead were not found in the worst burned parts of the plane
33:28autopsies will point to the real killer on flight 28
33:38of the 54 people who died in the cabin only six had suffered serious burns
33:43all the rest died from smoke inhalation
33:48it seems the smoke in the cabin was particularly lethal
33:52survivors tell investigators that the smoke was unbearable
33:56the smoke was really black and it was it was it was almost touching it was it was really weird
34:04and they say the effect of that was shocking
34:07immediately you took one breath of the smoke you began to feel debilitated
34:11and you knew that if you took another breath or two you weren't going to make it
34:20at the time of the Manchester accident
34:22the effects of fire on an airplane had been well studied and understood
34:27but the effects of smoke were not
34:33to figure out what made the smoke so toxic
34:36Trimble decides to recreate the fire that burned on flight 28
34:42we were trying to model not only the gases which were produced
34:46but also the kind of threat levels which were produced
34:49the smoke that filled the plane was from materials burning inside the cabin
34:54the foam in the seats
34:56the wool in the carpets
34:58and the plastic overhead bins all release poisonous fumes
35:02those conditions are recreated by burning those same materials
35:08Trimble discovers the passengers on flight 28 inhaled smoke
35:12that contained a deadly blend of poisonous gases
35:16including high levels of carbon monoxide and hydrogen cyanide
35:24now he desperately needs to find out if there's any way to protect airline passengers from that kind of smoke
35:32so it seemed to be pretty clear
35:35that unless we could protect people's respiratory systems from the assault from such combustion gases
35:44there was little that we could do to improve survival chances from aircraft fires
35:56over the course of five weeks
35:58investigators run dozens of tests
36:01experimenting with different filters
36:11they burn nearly a quarter ton of material to create the necessary smoke
36:16their dramatic conclusion
36:19it may have been possible to save passengers lives
36:23there was not the slightest doubt in my mind
36:25that in these situations
36:28in an aircraft cabin
36:29if it is being assaulted by combustion gases
36:34your chances of survival are vastly improved
36:38if you have smoke hood protection
36:46British air tours flight 28 had only enough smoke hoods for the crew
36:50they were never used
36:56Trimble's research indicates that smoke hoods for passengers could have saved lives
37:01there were hoods available
37:04both of the filter type and the breathable gas type
37:06which can provide a very high level of protection
37:09to people in these circumstances
37:17many of the passengers on flight 28 would have survived with a few more minutes of breathing time
37:26it was in a blink of an eye, you know, from the time, you know, we stopped on the runway
37:33you know, just within a few minutes
37:37it was all over really
37:41a full Boeing 737 is designed to be evacuated in less than two minutes
37:46so even without additional time
37:48more of the passengers on flight 28 should have been able to get off
37:56to discover why so many people never made it off the plane
37:59investigators turned to an unlikely source for the answer
38:11by law, airplane manufacturers must prove their planes can be evacuated quickly and safely
38:18when the 737 was introduced in the UK
38:21Boeing demonstrated that 130 people could get off the plane in just 75 seconds
38:27all public transport aircraft are certificated to the same criteria
38:31and that is that the total complement of passengers must be capable of evacuating from the aircraft
38:39using half the exits in the aircraft
38:42generally one side or the other
38:44within a maximum of 90 seconds
38:47but 90 seconds after flight 28 came to a stop
38:51most of the passengers were still on board
38:57the reason why the evacuation in Manchester wasn't achieved in 90 seconds
39:04is because the conditions in a real fire evacuation are completely different from the certification conditions
39:11the certification evacuation is conducted in clear conditions
39:15with no smoke that produces vision and overwhelms passengers
39:22within minutes of coming to a stop
39:24flight 28 filled with thick black smoke
39:27as soon as the smoke began to spill into the rear cabin
39:34and then flow forwards
39:38essentially that induced immediate panic
39:40in those who were so affected by the smoke
39:43because their respiration
39:44I mean the typical comment was I took one breath of smoke
39:47and I felt it was low my lungs
39:49was solidified
39:51you can imagine under these conditions
39:53that people have got to get away from the smoke
39:57and the people did this
39:58by basically clambering over the seats
40:00and other people in front of them
40:03in less than five minutes
40:05what should have been a survivable accident
40:07turned deadly
40:11to prevent future tragedies
40:13Britain's Civil Aviation Authority
40:15decides to learn more about people
40:17Helen Muir is a psychologist
40:19and a leading expert on how airplane design
40:22can influence survival
40:25she's asked to study the behaviour of passengers
40:28on flight 28 to figure out why so many died
40:34what we had to learn to do
40:36was to design the aircraft interior
40:38so even if we had what we might say
40:41was dysfunctional behaviour in totality
40:44we could accommodate the needs of individuals
40:47and their desperate rush to get out
40:51Muir configures a cabin to duplicate flight 28
40:54and fills it with volunteers
40:56then to have them act as though the plane's on fire
41:00she offers money to the first ones off
41:03and that produced behaviour that was quite unbelievable
41:06people went over seats
41:07they went round past each other
41:09all sorts of things
41:10and indeed when survivors from the actual Manchester accident
41:14came and saw the videos
41:15they said yeah, that's how it was
41:28the evacuation of flight 28 was slowed by the fact
41:32that passengers became jammed in the bulkhead opening
41:34separating the main cabin from the galley
41:46the bulkhead opening was 22 and a half inches wide
41:50just enough for one person to fit through
41:54but what they wanted to know was
41:56how much wider would they have to make it
41:59for people not to get stopped and blocked
42:02we were trying to do as much as we could
42:04to recreate the situation which had happened at Manchester
42:08and then to systematically vary the aircraft interior
42:11to see what changes would improve the situation for passengers
42:17Muir's tests showed the narrow bulkhead opening created bottlenecks
42:20that flight attendants had to constantly clear
42:24increasing the width to 30 inches
42:26greatly improved the movement of passengers
42:33but we showed through repeat testing
42:35that if you change the minimum gap from 20 to 30 inches
42:39you would dramatically improve the speed at which people could get out
42:43and you'd reduce the likelihood of people falling and slipping and so on
42:49As a result of Helen Muir's work
42:51a recommendation was made to increase the space between the bulkhead walls to 30 inches
42:58and introduce strip lighting to help guide passengers to exits
43:01even when they are blinded by smoke
43:08Muir also found a way to improve cabin safety without redesigning the cabin
43:13please sit down
43:15she conducted research on the behaviour of the cabin crew in emergencies
43:19and found that passengers get off a plane much faster with a highly assertive crew
43:29it's because we don't want people really making their own decisions
43:34we want people to do exactly what the cabin crew or the procedures state
43:39and we don't want people hesitating particularly at the door
43:44Helen Muir's research prompted manufacturers to redesign cabins to make them safer
43:50but one safety feature remains controversial
43:53smoke hoods
43:57Ed Trimble believes they should be mandatory on all commercial flights
44:01without a doubt
44:03without a doubt
44:06Helen Muir is less convinced
44:09she's studied how smoke hoods affect passenger behaviour
44:11and is worried they would slow down the orderly evacuation of an airplane
44:17we know you've only got literally one and a half to two minutes for everybody to get out
44:24what we don't want to have is something which is difficult to put on
44:28so it slows people getting down
44:29the most important lesson of British Air Tours Flight 28 is that seconds matter
44:35it's now universally accepted that it takes 90 seconds from the first sign of fire
44:41before it becomes unsurvivable
44:46the passengers on Flight 28 lost valuable time when the starboard side door jammed
44:52the investigators determined that the slide mechanism deployed too early
44:57preventing the door from opening
44:59there was a floor that led the slide containers lid to jam if the door is open too quickly
45:06after the Manchester accident Boeing quickly redesigned the system so that couldn't happen
45:14but the recommendations made by the AAIB weren't adopted quickly enough to save lives six years later
45:25in 1991 a Boeing 737 slammed into another plane on the runway in Los Angeles and caught fire
45:32many of the 22 people who died were overcome by smoke before they could get out
45:40but in 2005 the crash of an Air France jet in Toronto showed how much has changed since the Manchester
45:47accident
45:51all 309 people got off that plane in just 90 seconds no one died
46:01some major changes to commercial airliners
46:05all right the door's open
46:07came about because of a flight that never left the ground
46:13that's the only way I can resolve it with the death of 55 of my passengers
46:18the fact that flying is now safer
46:22I can't imagine anybody, you know, doesn't wish that it hadn't happened
46:29you know, despite what's been learnt and despite maybe the subsequent lives that have been changed
46:34just, you know, you'd give anything for it not to have happened
47:01you know, you'd give anything for it not to have happened