This is a request for proposal for comprehensive contractor support, including sustaining engineering, logistics, maintenance, and overhaul repair services, for the Dowty R391 propeller system and related parts used on C-130J aircraft. The services will support the U.S. Air Force, Navy, Marine Corps, Coast Guard, and Foreign Military Sales partners. The contractor will provide unit, supply, and depot support, including materials and services to sustain propulsion systems in peacetime and contingency operations. The acquisition is not set aside for small business.