LAX96LA333

The pilot lost directional control of the conventional gear airplane during the landing roll. He reported that on touchdown the surface winds shifted 90 degrees to the runway, and that he was unable to maintain directional control. The reported surface winds showed that a right 40 degrees crosswind component at 13 knots existed at the time of the accident.

On September 13, 1996, at 1106 hours Pacific daylight time, a Cessna 170, N2916D, dragged its left wing during the landing roll on runway 19L at Concord Airport, Concord, California. The pilot was completing a visual flight rules personal flight from Byron, California. The airplane, registered to and operated by the pilot, sustained substantial damage. The certificated private pilot, the sole occupant was not injured. Visual meteorological conditions prevailed. The flight originated at Concord Airport at 1015 and departed Byron Airport at 1050.

The pilot reported in a telephone interview conducted on September 13, 1996, that he had flown to Byron on a personal flight. He departed Byron Airport and flew directly to Concord Airport. While on final approach, he was applying the applicable flight controls to correct for a southwesterly crosswind. When the airplane crossed over the threshold, the winds ceased and he neutralized the flight controls.

During the landing roll, the southwesterly gust of wind unexpectedly raised the right wing and the left wing struck the runway. The airplane then veered to the left and came to rest on the dirt area east of the runway. The pilot reported no preimpact malfunctions or failures.

The pilot said in his accident report that on touchdown he observed the windsock swing 90 degrees to the runway. He applied maximum aileron and rudder correction to maintain directional control, but without success. The right wheel separated within 2 and 3 seconds and the left wing struck the ground.

The reported surface winds were 230 degrees at 13 knots.