>> they more cover the whole area and the ships just stay in the zone that they think they're -- best guesstimate they have. >> the ships are there to pick up wreckage. they don't have a very big scan area. but the aircraft can cover vast areas and they move quickly. and in terms of the aircraft, they try to consider how fast the aircraft go and how long they can stay on station and what sensors they use. maybe a slower aircraft, they might put in the area closer to port so it doesn't have to go out so far, and maybe the ones that can move faster can cover more ground in the farther area. >> when you look at all of the assets and countries putting all this effort in, at what point do you think they decide they can't sustain and do start pulling