On April 27, 1996, at about 1430 eastern daylight time (EDT), a Beech B55, N1580W, registered to Triple S Dynamics Inc., of Dallas, Texas, sustained substantial damage when the main landing gear collapsed during the landing roll, at Preston Glenn Field, in Lynchburg, Virginia. Visual meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan was filed. The certificated commercial pilot and the two passengers were not injured. The business flight was conducted under 14 CFR Part 91. The flight departed Islip, New York, at approximately 1200 EDT. The pilot reported that, when he performed a preflight inspection of the airplane prior to departure, he noticed that the right main landing gear strut was flat. The pilot stated that a mechanic serviced (inflated) the strut prior to his departure. The pilot stated: "The approach and landing...was normal...a slight crosswind from [the] right at 240 (landing runway was 21) was easily corrected for, and touchdown was on the runway centerline, main wheels first. Immediately upon nosewheel contact, the airplane began a swerve to the left which I could not control, even with full right rudder and brake. The left turn continued, off the runway edge and into a soft grassy area. The ground loop forces collapsed the main gear from side forces." The pilot reported that there was no mechanical malfunction, and indicated that he didn't know why the accident occurred. Postaccident examination of the airplane revealed no evidence of preimpact mechanical malfunction. The pilot's written statement indicated that the winds were out of 240 degrees at 18 knots.