again on a route search. they knew what the flight pattern of the aircraft is. you start there and immediately go to where the plane disappeared because you knew it was there and then as the airplane is flying in the direction of flight when it went missing the plane will drift down or if it came apart, if it floats down and then you look at the tides of the water and you can plot that and start looking there. that s where your concentrated search will be. you want to get ships to that area helicopters or other airplanes, get eyes out and look at that. weather is a big problem there. so they might have to fly below the clouds and us in the united states we have infrared devices or sensors to look for heat sources in the water. i m sure they have some aircraft equipped with that type of device or that sensor.