NTSB Factual Report

The pilot reported that during the landing roll, "all of a sudden the plane started ballooning up from a strong gust of wind, I lowered the nose of the airplane slightly as to avoid a stall." He reported that, "I was then forced back to the ground violently and once again ballooned up" and that the airplane, "ballooned up and was forced down 5 times." Once the porpoising ceased, the pilot taxied off the runway without further incident. A post flight inspection revealed substantial damage to the underside of the fuselage, the firewall, and the floor boards underneath the rudder pedals.

The pilot reported there were no pre-impact mechanical failures or malfunctions with the airframe or engine that would have precluded normal operation.

NTSB Probable Cause

The pilot's failure to maintain pitch control during the landing roll, which resulted in a porpoise.