Orbiter Processing Facility

An Orbiter Processing Facility (OPF) was one of three hangars where U.S. space shuttle orbiters underwent maintenance between flights. All three such facilities, OPF-1, OPF-2 and OPF-3, were located at NASA's Kennedy Space Center in Florida at Launch Complex 39.

They were located west of the Vehicle Assembly Building, where the orbiter was mated with its External Tank and Solid Rocket Boosters before transport to the launch pad. OPF-1 and OPF-2 are connected with a low bay between them, while OPF-3 is across the street.

OPF-3 was previously called the Orbiter Maintenance & Refurbishment Facility (OMRF), but was upgraded to a fully functioning OPF.

When a shuttle mission was completed, the orbiter was towed from the Shuttle Landing Facility to its assigned OPF where it spent several months (typically less than 100 days) being prepared for the next mission. Any remaining payloads from the previous mission were removed and the vehicle was fully inspected, tested, and refurbished.

Prior to rollout to the Vehicle Assembly Building, several weeks before scheduled launch, the orbiter was prepared for the next mission by installing mission flight kits, payloads, consumable fluids and gases where possible. Remaining payloads, fuels and fluids were installed on the pad closer to launch day. The last step before rollover to the VAB was weighing the orbiter to determine its center of gravity.

OPF-1 was closed following Atlantis' s rollout on June 29, 2012. In January 2014 it was announced that Boeing will lease the facility to enable the U.S. Air Force to efficiently land, recover, refurbish, and re-launch the X-37B unmanned spacecraft. In October 2014, NASA announced the signed agreement for the use of the facility, and Boeing is planning construction upgrades on OPF-1 for the X-37B Program, targeted to be complete in December 2014.

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