On July 5, 1999, about 1810 Eastern Daylight Time, a Boeing Stearman E-75, N1658M, was substantially damaged while landing at the Marston Mills Airport, Marston Mills, Massachusetts. The certificated commercial pilot and pilot rated passenger were not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight conducted under 14 CFR Part 91. The pilot, who was in the rear seat of the airplane, stated that after touching down on Runway 27, a 2,680 foot long grass runway, the airplane suddenly nosed over, and came to rest inverted. After the accident, the pilot asked his passenger, who was seated in the forward seat, if he had his feet on the brakes. The passenger replied yes. The pilot additionally stated to a Federal Aviation Administration Inspector that he did not brief the passenger on the operation or use of the brakes prior to flight, and there were no means of communication while the airplane was in flight. The winds reported by an airport located 7 miles to the east, at 1756, were from 310 degrees at 13 knots, gusting to 17 knots.