1 / 30

This undated image provided by the U.S. Navy shows Special Warfare Operator Petty Officer 1st Class (SEAL) Darrik C. Benson, 28, of Angwin, Calif. Benson was killed along with other SEALS in the Afghan Helicopter crash on Saturday, Aug. 11, 2011. (AP Photo/U.S. Navy)

This undated image provided by the U.S. Navy shows Special Warfare Operator Petty Officer 1st Class (SEAL) Darrik C. Benson, 28, of Angwin, Calif. Benson was killed along with other SEALS in the Afghan Helicopter crash on Saturday, Aug. 11, 2011. (AP Photo/U.S. Navy)

30 American troops die in helicopter crash

Portraits of the fallen troops who died when a rocket-propelled grenade fired by a Taliban insurgent downed their helicopter in Afghanistan (AP)