On October 17, 2005, at 1544 Pacific daylight time, a North American T-39A, N39FS, landed on runway 8 at the Mojave Airport (MHV), Mojave, California. During the landing roll the aircraft departed the runway and experienced a nose and right main landing gear collapse. The experimental certificated airplane was registered to, and operated by, BAE Systems Integrated Defense Solutions, Inc., Mojave, under the auspices of 14 CFR Part 91 as a test flight. The captain and copilot, who were both airline transport pilots, were not injured. The airplane sustained substantial damage. The flight departed MHV approximately 30 minutes prior to the accident for the local area test flight. Visual meteorological conditions prevailed and a flight plan was not filed. According to a statement provided by the captain, the flight was intended as a test flight after modifications were made to the nose, interior fittings, and ventral fin. He and the copilot calculated the takeoff and landing data based on weather at MHV. The captain indicated that the takeoff and landing criteria met the limits of runway 8 with a calculated landing distance over obstacles as 4,000 feet for a dry runway. Since the runway was wet they calculated a landing distance of 5,300 feet, and added a penalty due to the lack of speed brakes, which equated to 5,512 feet for no wind conditions. The crew estimated they had a 10-knot headwind, which they assumed would shorten the distance slightly. They briefed the project manager on their planned flight and departed after maintenance was completed on the aircraft. The flight crew conducted flight checks at or below 10,000 feet north of MHV. Due to rain showers in the area, they elected to return. They conducted a low pass and a touch-and-go landing to evaluate the winds and runway with no anomalies noted. The crew selected an approach flap setting and crossed the runway threshold at 125 knots. The captain reported the touchdown was just past the runway numbers, and the crew experienced normal braking action until around the 3,000-foot remaining point. At that point, the braking "seemed ineffective." The flight crew selected antiskid off and normal braking was attempted with limited effect. The captain elected not to abort the landing due to the limited remaining runway and the need to spool up the engines. The copilot was calling out speeds and distance remaining, and the captain remembered the airspeed was 60 knots with 2,000 feet of runway remaining. The copilot called "nose wheel steering" a couple seconds later but the steering had little effect on the aircraft. The pilot reported that the braking "became nil" as the aircraft slowed to about 30 knots. The airplane drifted to the right side of the runway and departed the runway surface. The nose wheel landing gear dug into the soft ground and folded aft, while the right main landing gear folded inward. The flight crew reported hydraulic fluid was visible throughout the cabin as they exited the airplane. The captain reported that there was no standing water on the runway; however, it was damp due to a rain shower that had moved past the airport about 15 minutes before landing. On September 27, 2005, the Mojave Spaceport General Manager issued an advisory notice informing operators that runway 8/26 would be NOTAM closed September 29th thru September 30th for Sealant Application and Remarking. The copilot's statement coincided with that of the captain's. The aircraft sustained substantial damage when the nose landing gear and right main gear collapsed. When the nose landing gear collapsed, it pushed the Nose Wheel Steering Control Valve through the floor of the cabin, leaving hydraulic fluid in the cabin and an 8-inch by 4-inch hole in the pressure vessel. In post accident examinations and tests of the accident aircraft, a Federal Aviation Administration Inspector from the Van Nuys, California, Flight Standards District Office noted no mechanical defects, correct instrument indications, and no indication of mechanical problems. During operational tests, the Inspector noted that there were no leaks in any hydraulic system and the brakes functioned properly using all systems. The Inspector also noted skid marks on the tires, but the depth did not go through the original grooves of the tire.