John Nance on Concorde Crash
July 25, 2000 -- An Air France Concorde jet crashed near Paris today shortly after taking off from Charles de Gaulle airport. According to the French Interior Ministry, all 109 people on board were killed. The plane hit a hotel and restaurant before crashing into the ground.
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 Nance. John, do we have any news yet as to what caused the crash?
ABCNEWS’ John 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.
Wang 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?
ABCNEWS’ John 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?
ABCNEWS’ John 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.
Terry Meiners 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?
ABCNEWS’ John 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.
Rick from rlc.net at 3:09pm ET
As as 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?
ABCNEWS’ John 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.
John 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?
ABCNEWS’ John 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?
ABCNEWS’ John 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.
Jim 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?
ABCNEWS’ John 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.
cstock1 at 3:20pm ET
Why has the Concorde been the only supersonic passenger jet built?
ABCNEWS’ John 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?
ABCNEWS’ John 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 Web site at www.john-nance.com, 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.
You can continue your discussion of the crash on our message board.