While in contact , the receiver pilot must continue to fly within the " air refueling envelope , " the area in which contact with the boom is safe . Moving outside of this envelope can damage the boom or lead to mid-air collision , for example the 1966 Palomares B-52 crash . If the receiving aircraft approaches the outer limits of the envelope , the boom operator will command the receiver pilot to correct his position and disconnect the boom if necessary
1966 Palomares B-52 crash
1966 Palomares B-52 crash
Aerial refueling