In February 1985, the US Navy issued a proposal request for a radar-carrying Battle Surveillance Airship System (BSAS), and in 1987 awarded the $168.9 million contract to Westinghouse Electric and Airship Industries (AI). The contract was for an airship that could be used as an airborne platform to detect the threat of sea-skimming missiles. The Westinghouse/Airship Industries Sentinel 5000 (redesignated YEZ-2A by the US Navy) was a prototype design that would have been the largest blimp ever constructed. With a crew of 10-15 accommodated in a triple-decked, partly pressurized gondola, the ship was to have been powered by two CRM Diesel engines with a supplementary General electric T700 turboprop. It would have had a 2-3 day endurance without fuel, with up to 30 days through refueling and replenishment from surface ships. Equipped with powerful radar, and nearly invisible to enemy radar due to its nonmetal substances, it was to be a formidable sentry for the Navy. AI contemplated a civil version of the 5000, which would accommodate between 140/300 passengers for luxury shuttle services and conventional scheduled flights. However the project was dependent on the success of the military program. The airship prototype did not fly until June 1991, at which time AI had collapsed and Westinghouse had taken full control of the program. Additional funding was canceled in 1995 and the development of the YEZ-2A program was discontinued.