On March 27, 2006, about 1300 pacific standard time, an experimental amateur built, Claypool RV-6A airplane, N428BC, sustained substantial damage during a hard landing and a nose over at Montgomery Field, San Diego, California. The airplane was being operated by the pilot as a visual flight rules (VFR) personal cross-country flight under Title 14, CFR Part 91, when the accident occurred. The solo private pilot received minor injuries. Visual meteorological conditions prevailed, and no flight plan was filed. The flight departed the Fresno Airport, Fresno California, about 1100.

During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on March 30, the pilot said the airplane landed hard and bounced. He said the airplane came down nose wheel first and bounced again, and on the third bounce the nose wheel tucked under the airplane, and the airplane nosed over. The pilot said there were no mechanical anomalies with the airplane prior to the accident. He said the airplane sustained structural damage to the nose gear, wings, and fuselage during the accident.

In a written statement to the NTSB dated April 3, the pilot wrote that he overshot the final approach course, and in an attempt to salvage the landing he forgot to put in the last notch of flaps, and crossed the runway threshold at 70 knots. He said once lined up with the runway, the airplane would not slow down. He reported that the airplane finally touched down hard, and then porpoised. He said each oscillation worsened until the airplane struck the runway and flipped over, about 2,000-2,500 feet down the runway. He reported he had several chances to go-around and reconfigure the airplane, but did not.