This is a procurement for 30 units of a flight-critical part that requires Government source approval prior to contract award. The Government intends to solicit and negotiate with only one pre-approved source, but all responsible sources may submit proposals or statements of interest. Proposals received within 45 days of the synopsis publication will be considered by the Government. An alternate source must qualify through the design control activity's procedures, which requires submitting detailed information with a proposal. The part requires unique design capability and manufacturing/repair knowledge held by approved sources.