Marines of the 2nd Reconnaissance Battalion practice their repelling from a UH-1 Huey helicopter at the Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., during Combined Arms Exercise 5-97, on May 5, 1997. The Marine Air Ground Task Force exercise is allowing these Marines to practice their desert warfare. Repelling from a helicopter allows the Marines to be inserted into a hostile environment in the least amount of time.