The 633d Contracting Squadron, located at 14 Burrell Street, building 67, Langley AFB, VA, has a requirement for the procurement of Diesel Engine Replacement. Please see attached Request for Quotation... The 633d Contracting Squadron, located at 14 Burrell Street, building 67, Langley AFB, VA, has a requirement for the procurement of Diesel Engine Replacement. Please see attached Request for Quotation. Additionally, the attached Statement of Requirement (SOR) for this combined synopsis/solicitation is incorporated by reference and outlines the specifications for this procurement.