TODAY | March 08, 2014
>> is a former investigator with the national transportation safety board . greg, good morning. thanks for coming on with us.
>> good morning, lester.
>> i've covered a lot of plane crashes , and virtually all of them, except for that air france one, which i also covered, occurred during takeoff and landing. when you hear about a plane disappearing at cruise altitude, what are the likely possibilities?
>> well, lester, that's probably the hardest thing for investigators, only because the workload for the crew is very minimal once the airplane gets to cruise. so, for the airplane to have disappeared, that is, for all the communication to instantaneously cease, you have to believe that there was something very catastrophic that either had the crew's full attention and required them to try and keep the airplane under control that they couldn't get a may day call off, or there was something structurally wrong with the aircraft, and they weren't able to maintain control and do all the things they needed to do to keep control of the airplane.
>> when a plane is over land, it's being handed off from air traffic control to air traffic controller . they're watching it on radar. when it's over the ocean, my understanding is the pilots have to report their position. how long a period before alarm bells would start going off and the realization this plane is off the grid?
>> well, there are flight tracks, especially in that part of the world, where you lose radar coverage. so, there are mandatory reporting points. so, the crew will check in with air traffic control , they'll give them an altitude, they'll give them a time, and then they'll give them their next estimated time at the next reporting point. if this doesn't happen, controllers will start making radio calls in the blind. they'll typically wait 30 minutes to 60 minutes and then start doing some other checking. they'll call the airlines, they'll talk to the airline to see if they've established communication with their discrete frequency that they use for company business.
>> and lastly, there is an emergency transmitter locator on the aircraft. how long will that continue to send off a signal?
>> well, we've got to be careful with that, because the emergency locator transmitter on the airplane -- if the airplane had crashed on land and survived the impact, then there is a probability that the actual elt would still be working. but when it goes into the water, it's a whole different story. and then all we have to do is use floats and debris floating on the surface to find the airplane. the only thing that has a pinger is the cockpit voice recorder and the flight data recorder , but that's under water. you won't get that signal, above water, over the top of the water using an airplane to try and find a signal.
>> all right, greg feith , thanks again for your expertise. appreciate having you on.