The Cessna CH-1 Skyhook is the only helicopter ever built by the Cessna Aircraft Company. It was the first helicopter to land on the summit of Pike's Peak and the last piston-engined helicopter to set the helicopter altitude record. The CH-1 had a single, two-bladed main rotor, and a front-mounted reciprocating engine which gave the aircraft a stable center-of-gravity (CG). Its semi-monocoque airframe greatly resembles its light airplane siblings built by Cessna. The CH-1 was named Skyhook for the civil market, similar to the marketing names used in the Cessna single engine airplane line, such as Skyhawk, Skylane and Skywagon. The United States Army designated the CH-1C as the YH-41 Seneca. While the CH-1 achieved several helicopter "firsts" and set a world record, it never became a commercial or military success.