NASA Crawler Transporter

The crawler transporters are a pair of tracked vehicles used to transport spacecraft from NASA's Vehicle Assembly Building (VAB) along the Crawlerway to Launch Complex 39. They were originally used to transport the Saturn IB and Saturn V rockets during the Apollo, Skylab and Apollo–Soyuz programs. They are currently used to transport the Space Shuttle. It is planned for them to carry the upcoming Ares I and Ares V rockets for the Constellation program as well. The crawler transporters carry vehicles on the Mobile Launcher Platform, and after each launch return to the pad to take the platform back to the VAB.

The crawler has 16 traction motors, powered by four 1,341 horsepower (1,000 kW) generators, in turn driven by two 2,750 horsepower (2,050 kW) Alco diesel engines. Two 1,006 horsepower (750 kW) generators, driven by two 1,065 horsepower (794 kW) engines, are used for jacking, steering, lighting, and ventilating. Two 201 horsepower (150 kW) generators are also available to power the Mobile Launcher Platform. The crawler's tanks hold 5,000 US gallons (19,000 l; 4,200 imp gal) of diesel fuel, and it burns 150 gal/mi (350 L/km).

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