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Michael Barr: Hijackings and aviation safety

Michael Barr, the director of aviation safety program, University of Southern California, joined the Chat room to answer questions about hijackings and aviation safety.

CNN: What are the cockpit procedures if you are being hijacked? Is there any way to send a secret signal to air traffic controllers?

BARR: Yes there are. There are certain phrases that the pilots are trained to use that will indicate to the air traffic controllers that a hijack is in progress Governments like to keep these procedures confidential so as not to help hijackers.

CHAT PARTICIPANT: Is it true that American Airlines had 163 security violations at Logan the last two years? What was done about it, and why was this information not made more publicly known?

BARR: The exact number of violations I would have to research with the FAA. But each violation requires a detailed answer and corrective action to the FAA.

CHAT PARTICIPANT: What safety precautions are being implemented to prevent this sort of thing from happening again?

BARR: Just this morning the FAA announced that there would no longer be baggage check in at curbs. Increased visibility of law enforcement at checkpoints. And there will be in the days to follow many more new procedures.

CHAT PARTICIPANT: What happened to sky marshals? When was that program ended?

BARR: The sky marshal program has not been totally ended, but this will be one of the areas that will be re-examined for funding so that more sky marshals can be available.

CHAT PARTICIPANT: Mr. Barr, how big a threat must a plane pose before it will be shot down?

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BARR: That is a very very difficult situation I do not think that there is any set procedure at this time. There may be a procedure coming out as a result of this event. There's not many pilots who want to shoot down an airliner with 350 people if a mistake had been made. Having been a fighter pilot myself, this is a very difficult position for the pilot.

CHAT PARTICIPANT: Mr. Barr, how can Americans ever feel safe on the airlines again? What precautions can passengers take?

BARR: I think passengers will have to show a patience with the increased security requirements. That will be the best way passengers can help. And it will take time for the passengers to return to the feeling of security that they possessed before this event. They will have to have confidence in government actions to prevent this from happening again.

CNN: What could the black boxes tell us?

BARR: First the black boxes have to be recovered in such a condition that they may be read. Secondly, we have to make sure that the terrorists did not turn off the circuit breakers or use non verbal communications in the cockpit. Since the voice cockpit recorder only picks up information from the microphone if it is active. But if it is active, it will give the exact conversation that is being conducted just prior to impact... for 30 minutes.

CHAT PARTICIPANT: Mr. Barr - Can you make an estimate by how much air fares will increase because of the extra costs on security?

BARR: I think there will be two types of increase in funding requirements. One will be the increase in tax to the government. The other will be the increased security costs to the airlines. Exactly how much I don't think you can determine at this time.

CHAT PARTICIPANT: What added safety precautions would you introduce?

BARR: First I would introduce a stronger door from the cabin to the cockpit. Second I would employ better training procedures for the security screeners. And compensate the screeners with higher wages and benefits. There are minimum wage workers responsible for the lives of passengers.

CHAT PARTICIPANT: How did the hijackers fly to their target without radar or flight plan?

BARR: They first most likely got into the general area of New York City. And on a clear day like that day was, the twin towers could be seen from many many miles away. They just had to point at them and hit them. This does require some flying skills.

CHAT PARTICIPANT: What do you think about the use of planes as weapons - could anyone have known?

BARR: Normally, what you do is what is called a risk assessment. You try to determine the probability of this happening. It seems government security gave this a very low probability.

CHAT PARTICIPANT: But aren't these precautions somewhat a waste when they won't be needed on 99.9999% of flights? Isn't this going to the extreme?

BARR: That is the problem that we as Americans have to accept. Because I don't think anyone wants to be that one-tenth of a percent or their families to be that one-tenth of a percent that are hijacked. We cannot take away all American freedoms, but we may have to increase our restrictions before we get on an aircraft.

CHAT PARTICIPANT: Why did not the air traffic control towers realize there was something amiss when four planes deviated from the flight plan?

BARR: We don't know what the air traffic controllers knew at the time. That information has not been released.

CHAT PARTICIPANT: Do flight attendants and pilots receive any special training in regards to hijacking? If so, what?

BARR: They do get training for hijacking There are procedures to be followed for hijacking.

CHAT PARTICIPANT: How is it possible that any plane could get into the restricted airspace above the Pentagon?

BARR: The airplane can fly anywhere it wants to fly. I'm sure the controllers were telling them that they were entering a restricted airspace and to turn away. But the terrorists had no intention of turning away. And the controller has no power to stop the aircraft from proceeding in its course.

CHAT PARTICIPANT: Is there going to be military involvement (placement of armed U.S. troops on board) with civilian airliners as security? Has anyone suggested it?

BARR: There is a law in the US called "Posse Commitatas" This law prevents the use of military in civilian law enforcement except in times of grave emergency. And I doubt if the U.S. wants to appear as a police state.

CNN: Do you have any final thoughts to share with us?

BARR: Its going to be a long time before this event is solved There will be more restrictions in the future for the flying public. And the government must stay active in their security procedures and not just for a short time following this event. We found that after TWA 800. Not all the security recommendations were implemented.

CNN: Thank you for joining us today.

Michael Barr joined the chat via telephone from Los Angeles, California. CNN provided a typist for Michael Barr. The above is an edited transcript of the interview, on Wednesday, September 12, 2001.

• USC Aviation Safety Program

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