The marine corps uses the Super Stallion in the amphibious assault role and for transporting heavy equipment. The US Navy also use the Super Stallion for vertical delivery and recovery of damaged aircraft on aircraft carriers.
In March 2004, a USMC analysis of alternatives (AoA) determined that a new-build airframe would be a more cost-effective solution. Sikorsky was awarded an initial system development and demonstration (SDD) contract for the new helicopter, which is designated CH-53K heavy-lift rotorcraft (HLR), in January 2006 and the full SDD contract in April 2006. The GE38-1B engine was selected to power the CH-53K in December 2006. Requirement is for 156 helicopters and service entry is planned for 2015.