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JOHN
J. NANCE
ABCNEWS.COM
CHAT
TRANSCRIPTS
Concorde Crashes Near Paris
Chat: ABCNEWS' Aviation Analyst John J. Nance

July
25, 2000 -
The plane's engine was on fire, said one eyewitness, and
a huge cloud of black smoke was visible in the air. What
could have happened to cause such a fire? Could it be related
to the cracks that were recently discovered in the wings
of several Concordes?
ABCNEWS' aviation analyst, John Nance, joined us for an
online chat about the crash. A transcript of the chat appears
below.
Moderator at 2:55pm ET
Welcome, John J. Nance. John, do we have any news yet as
to what caused the crash?
John J. Nance at 2:56pm ET
We don't have any firm indication at this point that would
justify saying that one particular thing was a primary cause.
But it is a very tantalizing element that a pilot observed
flame coming from one of the left engines in a way that
simply is not routine in a Concorde takeoff. This, followed
by the accident itself, is a very strong indication of engine
loss on takeoff at the most critical point in the Concorde's
flight.
In addition, since the Concorde can continue takeoff successfully,
in most circumstances, on three engines of its four, and
since all Concorde pilots are well trained to handle single
engine loss on takeoff, there is reason to believe that
we may have had a two-engine failure, which would explain
in many ways the inability of the aircraft to sustain flight.
What could happen in such a situation is an inability
to climb, and deteriorating airspeed, leading to a loss
of directional control as the thrust on the remaining engines
causes the airplane to roll over.
at 2:59pm ET
Could Mr. Nance address the issue regarding the fractures
on the planes? I would like more information as to how important
cracks on the wings are. It seems many older planes have
this "problem." How could this contribute to what appears
to be an engine problem?
John J. Nance at 3:00pm ET
More than likely, the fractures in the wing structure reported
by British Air a couple of days ago will play no role in
this accident. However, the old tried-and-true caveat from
the NTSB, "rule nothing in, rule nothing out," definitely
applies at this stage. It does not appear to me to be a
potential factor in an accident in which the wing was not
observed to fail. But the engines are highly suspect.
Aging aircraft structures will always develop cracks.
The problem is not the presence of cracks, but where they
are and how deep they run. In this case, British Air indicated
the fractures were structurally insignificant.
Moderator at 3:01pm ET
What is the safety record for this type of aircraft?
John J. Nance at 3:03pm ET
Until today, the safety record of the Concorde was essentially
perfect, in that it had traversed the ocean on a routine
basis for 30 years without losing a passenger or a plane.
Today's tragedy should in no way diminish the amazing level
of achievement of that operational record.
It's not just the fact that the Concord has flown accident-free
for 30 years that's significant, it's the fact that it is
the only supersonic passenger transport to be routinely
exposed to the rigors of supersonic flight. And yet, even
with such routine heavy use, it was still able to amass
a perfect record.
While it is true that there have been no other crashes
of a Concorde until today, there have been major maintenance
problems with the airplane over time, including the partial
loss of a vertical tail a number of years ago, and even
an encounter with freak weather by a Concorde going into
London just recently. But the point is that the redundancy
built into the Concorde has worked in all cases, until today.
at 3:05pm
ET
What minimum altitude and other conditions are necessary
for a Concorde (with one engine flamed out) to do a 180
and return safely to an airport?
John J. Nance at 3:07pm ET
I don't have the numbers in front of me, but I can tell
you that it is part of the normal operating envelope of
the airplane in all places that it is allowed to takeoff
and land. It should be able to lose either of the critical
engines (the outboard engines - one or four), even at full
gross weight, and be able to safely climb to an altitude
that would permit it to maneuver for and turn to the airfield
it had just left, or another alternate airfield.
In other words, a single engine loss on takeoff should
be essentially a non-event, which is what makes this accident
all the more puzzling and unanticipatable. The only reasonable
explanation to begin with in such a situation as today,
in the absence of any other mechanical failures on board,
would be that two engines, not one, failed.
from rlc.net
at 3:09pm ET
As a GA pilot, the first thing that comes into my mind is
that something, such as a bird, was pulled into the intake.
Could that cause a fire? What do you think?
John J. Nance at 3:10pm ET
There are many reasons why a turbojet engine can fail and
fail catastrophically. Birds are usually not one of those
reasons, because the engine at full power is usually robust
enough to essentially chew its way through a small number
of birds.
That equation changes when an engine ingests a lot of
birds at once, or large birds. In these early hours after
the accident, we have no indication one way or another of
whether bird ingestion might have played a role here. But
it is certainly an area for immediate concern and investigation.
at 3:11pm ET
I understand that the aircraft has a "perfect" safety record;
but compared to other aircraft, such as the 737/747, how
many planes exist, how many flights do they make and approximately
how many passengers do they transport each year?
John J. Nance at 3:13pm ET
I could be off by one or two, but I believe we still have
17 Concorde airframes in existence, of which, until today,
13 were in constant use. A bit of quick math gives me an
estimate of approximately 150,000 passengers per year traveling
on the Concorde at the peak of its operational history.
A 737, for instance, has over 2,500 individual aircraft
flying throughout the world, more than likely carrying over
seven to ten million, if not many times more, passengers
per year. The Concorde carries just about 100 passengers
in what is a fairly small cabin, with extremely small windows.
All seats are first class, and the aircraft has a top speed
of just over 1,300 miles an hour.
Moderator at 3:15pm ET
Could this crash have been caused by pilot error?
John J. Nance at 3:16pm ET
While the term "pilot error" is always raised after an accident,
very few accidents actually result from pilot error, in
that the term denotes a pilot making a conscious decision
to do something wrong. Most accidents erroneously labeled
as pilot error result from human error, which is an inadvertent
failure of a pilot or pilots, due to their status of being
imperfect humans.
In this case, the actions and reactions of the flight
crew will be studied with great care to determine not whether
they are at fault, but how their actions either contributed
to an attempted recovery, or contributed to the problem.
The point of such an examination is always to prevent a
recurrence, not to place blame. It is difficult, however,
to see any potential indication of human error in the little
we know so far of this accident.
at 3:18pm ET
Isn't the Concorde scheduled to be decommissioned soon?
How many more years of service have they been designed to
deliver?
John J. Nance at 3:20pm ET
Good point, Jim. Both British Air and Air France have tentatively
planned to terminate Concorde operation in 2005. How those
plans will be changed now, we'll have to see.
The aircraft really did not have a specific design life
when it was produced. But like most commercial aircraft,
continuous maintenance makes the real lifespan very ambiguous.
What we've learned in the past 15 years is that older airplanes
can be safely flown almost indefinitely, but the increasing
cost of maintenance as they age makes continued operation
uneconomical.
at 3:20pm
ET
Why has the Concorde been the only supersonic passenger
jet built?
John J. Nance at 3:22pm ET
The Concorde has been the only supersonic transport because
supersonic commercial flight is, basically, uneconomical.
Unfortunately, the Concorde has never made money, and it
is still questionable that, even applying 21st-Century technology,
anyone could construct a commercial supersonic transport
that could charge low enough fares to attract enough people
to still make a profit.
There are parallels in other forms of transportation.
For instance, it would be possible to build an inner-city
bus with great smoothness and hydraulic support to dampen
out the affects of curves, and with great increases in safety,
but such a bus would cost millions to produce, and a bus
operator would be unable to even make enough money to buy
it. The Concorde has a similar economic conundrum.
Moderator at 3:23pm ET
Do pilots need special training to fly the Concorde?
John J. Nance at 3:24pm ET
Any competent commercial airline pilot should be trainable
as a Concorde pilot, but there is no doubt that the training
course is significantly more rigorous and demanding than
that of the average passenger jet.
The reason for that is twofold: First, the Concorde's
systems are significantly more complex, especially fuel
systems. And secondly, the speeds and flight dynamics of
the airplane require much more planning and numerical calculation
by the pilots than do the average jet. But the idea that
near-astronaut-quality pilots are needed to fly the Concorde
is quite false.
Within a couple of hours, I will have some expanded
discussion of this posted on my website and will attempt
to keep that updated over the next week.
Moderator at 3:27pm ET
Thanks, John. Stay with ABCNEWS.com for continuing coverage
of today's Concorde crash.
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