NASA's Langley Research Center. Here, a team of engineers tests the performance of gear struts, tires, and brake systems on military, commercial and research aircraft, including the space shuttle. Neat video.
ALDF engineers do much of their primary research with a 110,000-pound steel-tube carriage that carries landing gear down two steel rails to a "landing" on a short patch of runway. Propelled by a high-pressure water jet, the carriage, which looks like the kind of modern art sculpture you see in front of government buildings, is capable of reaching a speed of 265 mph and an acceleration of 20 Gs on its short trip down the track.