The mountain ice routes of California's Sierra Nevada are at their prime in late September and early October, routes such as the Mendel Couloirs where Yvon Chouinard tested out the first prototype curved ice tools, are popular at this time of year. Two climbers got a bit of a surprise last week when they found a frozen body in the small Mendel glacier at the base of the ice couloirs. Investigators believe that they are the remains of a World War II airman. The body was 80% encased in ice and was wearing an unopened parachute which had "U.S. Army Air Corps.," stencilled on it. "During World War II, many military training centers were situated in California's Central Valley and used training routes over the Sierra Nevada. Flight training sometimes was fatal -- during the 1940s and '50s, up to two dozen planes crashed in the craggy backcountry of Kings Canyon and the adjoining Sequoia National Park," said Jody Lyle, a spokesperson for Kings Canyon National Park in the San Francisco Chronicle online.