This is a sole-source solicitation for a flight-critical part or repair, open only to government-approved sources. Unapproved sources must submit a full source approval package with their proposal, but the approval process is lengthy and may preclude award. The government will not delay an award to wait for a new source to be approved. The delivery terms are FOB Origin. Interested parties can identify their capability to provide a commercial equivalent within 15 days of the notice's issuance.