British Senior Aircraftsman Jason Hammond, with the No. 1419 Flight, 78 Squadron Royal Air Force, marks distance for U.S. Marine Corps pilots with the Marine Heavy Helicopter Squadron 464 (HMH-464) during a tactical recovery of aircraft and personnel (TRAP) mission at an undisclosed location in the Helmand Province, Afghanistan, Sept. 15, 2011. HMH-464 personnel perform TRAP missions to retrieve U.S. and U.K. armed forces equipment and conducts investigations in support of the International Security Assistance Force.