It is an indelible
image, heavy with symbolism: the photograph taken on 25 July last
year at the moment Concorde became a technological Icarus. The great
white bird rears up over runway 26 at Charles de Gaulle, immediately
after takeoff. Already mortally wounded, flames bleed uncontrollably
from beneath the left-hand wing. Less than two minutes later, the
world's only supersonic airliner will fling itself into the Paris
suburb of Gonesse, killing all 109 on board and another five on
In the 10 months since the crash, the official investigation
into its causes has focused almost entirely on the fire. According
to the French accident investigation bureau, the BEA, it broke
out when the plane passed over a strip of metal on the runway.
A tyre burst; a chunk of rubber thudded into a fuel tank inside
the wing; jet fuel poured out of a hole and ignited.
The hot gases caused two of the engines to falter, and despite
a valiant struggle by Captain Christian Marty, a daredevil skier
who once crossed the Atlantic on a windsurf board, the loss of
thrust made the crash inevitable.
This 'single cause' explanation is why the Civil Aviation Authority
grounded British Airways' seven Concordes three weeks after the
disaster. Its chairman, Sir Malcolm Field, said: ' It is clear
to all of us in the CAA that a tyre burst alone should never cause
the loss of a public transport aircraft tyre debris alone is thought
to have led to this catastrophic accident.'
An investigation by The Observer suggests the truth is much more
complicated - and as far as Air France is concerned, far more
worrying. In the words of John Hutchinson, a BA Concorde captain
for 15 years, the fire on its own should have been 'eminently
survivable; the pilot should have been able to fly his way out
of trouble'. The reason why he failed to do so, Hutchinson believes,
was a lethal combination of operational error and 'negligence'
by the maintenance department of Air France. This appears to have
been a crash with more than one contributing factor, most of which
Go back to that photograph. An amazing picture: but where was
it taken? The answer is: inside an Air France Boeing 747 which
had just landed from Japan, and was waiting to cross Concorde's
runway on its way back to the terminal. Its passengers included
Jacques Chirac and his wife, the President and first lady of France,
returning from the G7 summit.
Concorde looks to be nearby because it had been close to hitting
the 747, an event which would have turned both aircraft into a
giant fireball. Veering wildly to the left, like a recalcitrant
supermarket trolley with a jammed wheel, Concorde's undercarriage
had locked askew.
When Marty pulled back on the control column to raise the nose
and take to the air - the process pilots call 'rotation' - the
plane's airspeed was only 188 knots, 11 knots below the minimum
recommended velocity (VR) required for this manoeuvre.
But he had no choice: the plane was about to leave the tarmac
altogether and plough into the soft and bumpy grass at its side.
That might have ripped off the landing gear, leaving Concorde
to overturn and blow up on its own. If not, the 747 lay straight
ahead. So he took to the air, although he knew he was travelling
too slowly, which would impair the damaged plane's chances of
The BEA's interim report, published last January, notes that
according to the cockpit voice record, the instant before Marty
rotated, Jean Marcot, his co-pilot, screamed: 'Watch out!' The
report states: 'At this stage it is not possible to explain this
exclamation.' Marcot was at the front of a Concorde thundering
off a runway at 200mph towards a 747 carrying his head of state:
his exclamation seems reasonably explicable.
But why was the plane in this disastrous position? Shocking evidence
now emerging suggests that the underlying reason may have been
that Air France Concorde F-BTSC had not been properly maintained.
The airline's ground staff had failed to replace a 'spacer', a
vital component of the landing gear which keeps the wheels in
proper alignment, when they serviced and reassembled the plane's
undercarriage four days before the disaster. Although the BEA
disputes it, there is compelling evidence that it was the missing
spacer which may have caused the plane to skew to the left, so
forcing Marty to leave the ground too early.
At the same time, the plane was operating outside its legally
certified limits. When it stood at the end of the runway, ready
to roll, it was more than six tonnes over its approved maximum
takeoff weight for the given conditions, with its centre of gravity
pushed dangerously far to the rear. According to Hutchinson, even
before the blowout, Marty was already 'pushing the envelope' of
safe flying explored by the test pilots when the plane was being
developed in the early 1970s.
Had the plane not hit the metal strip, Marty would almost certainly
have got away with it. Faced with an emergency, with his plane
in the air flying below a sustainable speed, his options were
severely compromised. According to Hutchinson, Marty found himself
trying to save a one-time thoroughbred which was 'responding like
a flying pancake, like a sack of potatoes'.
The Observer's investigation suggests Concorde need not have
been grounded at all. Now undergoing a £30 million refit to equip
the fuel tanks with new kevlar linings, it was already basically
safe. As for Air France, the sense of sorrow over what took place
remains palpable: the crash was their worst nightmare. Their lawyers
are close to reaching a settlement with the families of the 109
German victims, luxury package tourists from Münchengladbach about
to start the holiday of a lifetime. Each family has been offered
about £1m - the largest settlement in German legal history.
Disclosure that this may not have been a 'single cause' catastrophe
may place this in jeopardy. Because the plane was bound for New
York, the relatives would be entitled to sue in America. If the
courts there found Air France culpable, the damages they might
award could make £1m seem trivial.
Most of the raw data about the crash can be found on the internet,
in the two reports already published by the BEA. Its final report
is due in a few weeks' time. Meanwhile, a separate inquiry is
being conducted by an investigating judge. The missing undercarriage
spacer, and the effects this had on Flight 4590, are now emerging
as the judicial investigation's central issues. If the French
courts decide there is sufficient evidence, they have the power
to charge Air France with 'homicide involuntaire' - what British
law would term corporate manslaughter.
The stresses on Concorde's landing gear are unusually severe.
Unlike ordinary aircraft, its delta wings generate hardly any
'lift' until the captain pulls up the nose and pitches the plane
upwards at an angle of 18 degrees at the point of rotation. Until
then, the wheels and bogeys will bear all of Concorde's weight
- in the case of a fully-laden plane at takeoff, about 185 tonnes.
The procedures both Air France and British Airways impose on
their ground crews reflect the obvious danger of getting anything
wrong. At regular intervals of a few hundred flying hours, the
various load-bearing components become 'lifed', and must be replaced.
When the undercarriage bogeys are taken apart and reassembled,
the work must be done according to a rigid formula, and rigorously
inspected and assessed.
Concorde F-BTSC went into the hangar at Charles de Gaulle on
18 July, a week before the crash. The part which was 'lifed' was
the left undercarriage 'beam' - the horizontal tube through which
the two wheel axles pass at each end. In the middle is a low-friction
pivot which connects the beam to the vertical 'leg' extending
down from inside the wing. The bits of the pivot which bear the
load are two steel 'shear bushes'.
To keep them in position, they are separated by the spacer: a
piece of grey, anodised aluminium about five inches in diameter
and twelve inches long. When the plane left the hangar on 21 July,
the spacer was missing. After the crash, it was found in the Air
France workshop, still attached to the old beam which had been
In the days before the accident, the aircraft flew to New York
and back twice. At first, the load-bearing shear bushes remained
in the right positions. But each time the plane took off, the
landing gear was retracted into the wing. On the ground, the two
shear bushes are positioned horizontally, on either side of the
beam. With the gear retracted, the right-hand bush lies vertically
above the left.
On F-BTSC, it began to slip, down into the gap where there should
have been a spacer. By the day of the crash, it had moved about
seven inches, until the two washers were almost touching. Instead
of being held firmly in a snug-fitting pivot, the beam and the
wheels were wobbling, with about three degrees of movement possible
in any direction. As the plane taxied to the start of the runway,
there was nothing to keep the front wheels of the undercarriage
in line with the back. The supermarket trolley was ready to jam.
Exactly when it started to do so is uncertain. Jean-Marie Chauve,
who flew Concordes with Air France until his retirement six years
ago, and Michel Suaud, for many years a Concorde flight engineer,
believe the undercarriage was already out of alignment when the
plane began to move down the runway.
They have spent the past six months preparing a 60-page report
on the crash, which they have submitted to the investigating judge.
Chauve said: 'The acceleration was abnormally slow from the start.
There was something retarding the aircraft, holding it back.'
In his view, it must have been friction from the undercarriage.
Chauve and Suaud's report contains detailed calculations which
conclude that without this retardation, the plane would have taken
off 1,694 metres from the start of the runway - before reaching
the fateful metal strip.
The BEA contests these findings, saying that the acceleration
was normal until the tyre burst. It also maintains that even after
the blowout, the missing spacer was insignificant.
The BEA's critics say that once the tyre burst, the load on the
three remaining tyres became uneven, and even if the wheels had
been more or less straight before, they now twisted disastrously
to the side. The 'smoking gun' is a remarkable series of photographs
in the BEA's own preliminary report. They show unmistakably the
skid marks of four tyres, heading off the runway on to its concrete
shoulder, almost reaching the rough grass beyond.
In one picture, the foreground depicts a smashed yellow steel
landing light on the very edge of the made-up surface, which was
clipped by the aircraft as Marty tried to wrest it into the air.
Industry sources have confirmed that this probably had further,
damaging results. Until then the number one engine had been functioning
almost normally but when the plane hit the landing light it ingested
hard material which caused it to surge and fail. This hard material,
the sources say, was probably parts of the broken light.
And as one industry insider put it: 'You would not see four marks
if the wheels had been straight, with the back wheels behind the
front. And you should not see such marks at all after a normal
takeoff. This plane was skidding sideways. It was out of control.'
John Hutchinson said: 'The blowout alone would not cause these
marks. You'd get intermittent blobs from flapping rubber, but
these are very clearly skids.' Overall, the effect on the plane
was like trying to take off in an exceptional crosswind - a situation
Concorde pilots are trained to avoid at all costs. The captain
tried to overcome the leftward drift by turning the rudder to
the right. It made negligible difference.
In its interim report, and in a statement issued last month after
Captain Chauve submitted his dossier to the judge, the BEA said
that the leftwards 'yaw' was caused not by the faulty landing
gear but by 'the loss of thrust from engines one and two'.
There are several problems with this analysis. First, as the
BEA's own published data reveals, the thrust from engine one was
almost normal until the end of the skid, when it took in the parts
of the landing light. It is simply not true that the yaw began
when both engines failed.
Second, those who fly the plane say that a loss of engine power
will not cause an uncontrollable yaw. Concorde's engines, unlike,
say, a 747, are not mounted out near the wingtips but close to
the tail and fuselage. The Observer has spoken to five former
and serving Concorde captains and flying officers. All have repeatedly
experienced the loss of an engine shortly before takeoff in the
computerised Concorde training simulator; one of them, twice,
has done so for real. All agree, in John Hutchinson's words, that
'it's no big deal at all. You're not using anything like the full
amount of rudder to keep the plane straight; the yaw is totally
Finally, there are the skid marks. Yesterday, the BEA claimed
the plane had not skidded at all. Its chief spokeswoman, Helen
Bastianelli, confirmed that the wheels were 'not in a symmetric
trajectory' - in other words out of alignment - when the Concorde
took off, the first time the BEA has made this crucial disclosure.
But despite the photographic evidence, she still insisted the
yaw was caused by engine failure - on the grounds that photos
or no photos, there was no sign of skid marks.
Later I was telephoned by Philip Swan, an Englishman who works
for the BEA in Le Bourget - the airstrip near Gonesse where Marty
was hoping to try to land. He accepted that the pictures did show
the marks of four tyres, and that they were clearly out of alignment.
But he concluded: 'The photograph does depict that the tyres of
the aircraft made sideways marks under stress. But I prefer not
to use the term skid.' Think of your car, resisting your attempts
to drive it straight, lurching off to the left. The BEA would
say those black smears it leaves behind on the road are not evidence
of a skid, merely the marks of the wheels moving sideways under
The fact that Marty had to rotate his plane 11 knots below its
stipulated rotation velocity was always going to make it difficult
to save. In the event, he never got close to 'V2,' the 220-knot
airspeed which would have represented stable flight. For a few
seconds in the agonising minute between takeoff and catastrophe
he got up to about 210 knots, only for the number one engine -
which had begun to recover - to fail for a second time.
But despite everything already against him - the skewed bogey;
the fire - other avoidable factors were further loading the dice,
making it still more difficult to rescue the plane. When Marty
paused at the start of the runway, his instruments told him that
his Concorde had 1.2 tonnes of extra fuel which should have been
burnt during the taxi.
In addition, it contained 19 bags of luggage which were not included
on the manifest, and had been loaded at the last minute, weighing
a further 500 kg. These took the total mass to about 186 tonnes
- a tonne above the aircraft's certified 'maximum structural weight'
- the weight its physical components were designed and tested
to carry in safety.
Meanwhile, in the interval between Concorde's leaving the terminal
and reaching the start of the runway, something very important
had changed: the wind. It had been still. Now, as the control
tower told Marty, he had an eight knot tailwind. The first thing
pilots learn is that one takes off against the wind. Yet as the
voice record makes clear, Marty and his crew seemed not to react
to this information at all.
Had they paused for a moment, they might have recomputed the
data on which they had planned their takeoff. If they had, they
would have learnt a very worrying fact. Flying a tonne over maximum
structural weight was theoretically unlawful, but was not an outrageous
However, more important than this measure is what pilots call
the RTOW, the regulated takeoff weight: a limit set according
to detailed tables for a given plane in the conditions obtaining
at a particular time and place. As Marty released the brake on
25 July last year with the eight-knot wind behind him, the tailwind
meant that Concorde's RTOW was just 180 tonnes - at least six
tonnes less than the weight of Flight 4590.
John Hutchinson said: 'The change in the wind was an incredible
revelation, and no one says anything. Marty should have done the
sums and told the tower, "Hang on, we've got to redo our
calculations".' Once he realised how far he was above the
RTOW, he should have insisted on taxiing back to the other end
of the runway - as most Concorde pilots have done several times
- and taken off against the wind. 'If I'm honest, I've probably
taken off 30, 40 kg overweight - after all, you can never be sure
because you don't weigh the passengers or the hand baggage. But
not six tonnes! They were already at the limits of the envelope.
Once the wind changed, they were beyond it.'
The extra weight had a further consequence beyond simply making
it harder to get into the air. It shifted the centre of gravity
backwards: the extra bags almost certainly went into the rear
hold, and all the extra fuel was in the rearmost tank, number
11. A plane's centre of gravity is expressed as a percentage:
so many per cent 'fore' or 'aft'.
Brian Trubshaw and John Cochrane, Concorde's two test pilots
when the aircraft was being developed in the early 1970s, set
the aft operating limit at 54 per cent - beyond that, they found,
it risked becoming uncontrollable, likely to rear up backwards
and crash, exactly as Flight 4590 did in its final moments over
The doomed plane's centre of gravity went beyond 54 per cent.
The BEA states a figure of 54.2 per cent. A senior industry source,
who cannot be named for contractual reasons, says the true figure
may have been worse: with the extra fuel and bags, it may have
been up to 54.6 per cent.
He said: 'This is very significant. Even in a takeoff with all
four engines working normally, you are well beyond the point where
the test pilots would have been prepared to tread.' And as the
fuel gushed from the hole in the forward number five tank, the
centre of gravity moved still further back. Once again, Air France
and Marty had closed off their options.
Marty's crew was to do so one final time. When the plane was
just 25 feet off the ground, Gilles Jardinaud, the flight engineer,
shut down the ailing number two engine. Both French and British
pilots say it was another disastrous mistake, which breached all
set procedures. The engine itself was not on fire, and as the
tank emptied and the fire burnt itself out, it would probably
have recovered. The fixed drill for shutting down an engine requires
the crew to wait until the flight is stable at 400 feet, and to
do so then only on a set of commands from the captain.
In a comment which might be applied to the whole unfolding tragedy,
John Hutchinson said: 'Discipline had broken down. The captain
doesn't know what's happening; the co-pilot doesn't know; it's
a shambles. Once you deviate from rules and procedures, it's chaos.'
British Airways says its transatlantic service will resume in
the autumn, once the modifications have been tested. It plans
to relaunch it with a plane full of celebrities, who have already
been treated to lavish presentations in London and New York, and
invited to marvel at new seats and lavatories designed by Terence
Last week, I put the results of The Observer's investigation
to Air France: a spokesman said the airline wished to make no
comment on any aspect of the crash.
But there will not be another supersonic airliner in most of
our lifetimes. The paramount icon of what Harold Wilson once called
'the white heat of the technological revolution,' Concorde has
no competitors. The headline The Observer used in reporting the
crash last summer was 'Death of a Dream'.
That dream was shared by the Germans from Münchengladbach who
chattered and sang in the Charles de Gaulle VIP departure lounge,
happy to ignore a 45-minute delay; it continues to inspire the
correspondents to the many Concorde internet chat rooms and bulletin
Previous reports of the tragedy which left it tarnished, perhaps
beyond salvage, have described the crash as an 'act of God', a
freak occurrence which exposed a fatal structural weakness in
the aircraft which could have appeared at any time.
Following the lead from the BEA, the international media have
looked at previous tyre blowouts, suggesting that any one of them
could have set in motion an ineluctable chain reaction; they have
taken as a given the proposition that once the fire began, and
hot gases interfered with the running of the left-hand engines,
then the disaster that followed on 25 July last year was inevitable.
The investigation by The Observer suggests the truth may not
only be more complicated, but also sadder, more sordid. Men, not
God, caused Concorde to crash, and their omissions and errors
may have turned an escapable mishap to catastrophe.
'The accident appalled me beyond belief,' John Hutchinson said.
'The images of the plane and the crash will live in my mind forever.
But it now seems that a single failing may not have caused the
'In simple terms, if all the procedures and drills had been followed,
if there had not been shortcuts and blind eyes, the crash might
not have happened.'