to accommodate Boeing 767-400 class aircraft), a second hangar for 767 for lease, and a third hangar designed to accommodate Boeing 707-300 class aircraft. Building 9001 (Tinker Aerospace Complex) The second of the public-private partnerships is Building 9001, originally known as the Tinker Aerospace Complex housed in the former General Motors Oklahoma City Assembly Plant located west of the runway on the south side of the base, north of I-240. A 50-year lease-purchase agreement was executed in September 2008 between Oklahoma County and the Air Force, covering the 2.5 million square foot (353,000 m2) facility and . Previously, the largest single building at the base was Building 3001 at . Tinker has leased about 4/5 of the facility and will host some current 76th Maintenance Wing operations as well as other Department of Defense missions, including work on the C-17 engines, joint strike fighter engines and core work on the new KC-46 tanker. Work being transferred to the complex is currently being done at 69 separate facilities on base, many of which are World War II-era temporary buildings located in runway clear zones. Burlington Northern Santa Fe provides a rail spur into the complex. In 2014 Oklahoma County agreed to issue $10 million in bonds to help finance the purchase of a BNSF Railway marshaling yard, just north of the TAC building. In addition to providing space for the work of the Oklahoma City Air Logistics Center, the Tinker Aerospace Complex can also be used to house public/private business partnerships. Currently, there are three programs. The Cooperative Research and Development Partnership has the objective of advancing science and technology to meet Air Force requirements and transferring technology into the commercial marketplace (CRADA, governed by Title 15 USC 3710a). Public-Private Partnerships, or statutory partnering, is where the government acts as a seller to private industry in either a direct sales agreement, Workshare Partnering Agreement, or a Facilities Use Agreement (governed by Title 10 USC 2474). Finally, the Enhanced Use Lease requires Congressional approval and full fair market value rent for underutilized Air Force assets(governed by 10 USC 2667). Based units Flying and notable non-flying units based at Tinker Air Force Base. Units marked GSU are Geographically Separate Units, which although based at Tinker, are subordinate to a parent unit based at another location. United States Air Force Air Force Materiel Command (AFMC) 72nd Air Base Wing (Host wing) Headquarters 72nd Air