Irish rescue helicopters also took part in the operation as well as a spotter plane.

BBC: Hunt for five missing crew of sunken Swanland halts

As Robbins, 44, and his 15-man crew approach the school--identified earlier by spotter plane--they lower two 40-foot boats into the water.

FORBES: Magazine Article

Soon after the sky cleared one of his aides claimed to have heard the engine of a spotter plane and there was general alarm, but when I looked there was nothing.

NPR: Ronan Bennett: From Prisoner to Writer