Space Shuttle Pathfinder

The Space Shuttle Orbiter Pathfinder (honorary Orbiter Vehicle Designation: OV-098) is a Space Shuttle test simulator made of steel and wood. Constructed by NASA in 1977 as an unnamed facilities test article, it was purchased in the early 1980s by the America-Japan Society, Inc. which had it refurbished, named it, and placed it on display in the Great Space Shuttle Exhibition in Tokyo. The mockup was later returned to the United States and placed on permanent display at the U.S. Space & Rocket Center in Huntsville, Alabama, in May 1988.

Activities
Originally unnamed, the simulator was built at the Marshall Space Flight Center in 1977 for use in activities such as checking roadway clearances, crane capabilities and fits within structures. It was later shipped by barge to the Kennedy Space Center and was used for ground crew testing in the Vehicle Assembly Building, Orbiter Processing Facility, and Shuttle Landing Facility. Pathfinder is approximately the same size, shape and weight of an actual Orbiter. Using Pathfinder allowed for facilities testing without requiring use of the more delicate and expensive Enterprise.

Refurbishment
After sitting in storage for many years, the America-Japan Society, Inc. obtained the wood and steel mock-up at a cost of US$1 million and hired Teledyne Brown Engineering to refurbish it to more closely resemble an actual Space Shuttle. It was named Pathfinder and displayed at the Great Space Shuttle Exposition in Tokyo from June 1983 to August 1984.

U.S. Space & Rocket Center
After the exhibit, Pathfinder was returned to the United States. In May 1988, it was placed on display at the U.S. Space & Rocket Center in Huntsville, Alabama. The 89-ton mockup is displayed as part of a complete Shuttle stack comprising the Pathfinder, the MPTA-ET external tank, which was used for propulsion tests with MPTA-098, and two prototype Advanced Solid Rocket Booster casings, which were developed after the Challenger accident but never put into production.

In 1999, NASA removed the forward assemblies from each SRB attached to the Pathfinder stack. Although the SRBs are recovered and reused after each flight, several of the forward assemblies had been damaged or lost over the history of the Space Shuttle program necessitating requisition of those attached to the Pathfinder stack as spares.

In 2008, repairs were made to the forward part of the mockup after decades of exposure to the weather had corroded the floor section near the vehicle's nose. This corrosion caused the "belly pan" to drop from a mounting bracket onto the external tank. The damaged area was part of the fiberglass and plywood added to the mockup before its exhibition in Japan.