dr. allen dale former ntsb air safety investigator investigator.u have been following this story as we have throughout the morning getting more details. base ond the information that you have where do you believe this plane, this missing plane could be? how soon do you think rescuers can get to it? >> obviously, suzanne, that's a difficult question. one thing i will say about this particular type of aircraft the air bus, it does have what is called a ditching switch. this is a mechanical device that can be activated by the pilots and it seals the bottom of the aircraft if they were able to get it on to the water it should float for a considerable period of time. so that's one advantage of the air bus over other types of airliners. but we of course, don't know that it made it to the surface of the water or for that matter to land. we certainly remember the airal jeer accident which was a mcdonald douglas aircraft similar in size. it disappeared over north africa. again, like this situation, the pilot asked to deviate around severe weather. in that c