Accident Details
On September 7, 2013, at 0900 central daylight time, an experimental-homebuilt Barrow Rose Parrakeet A-4C airplane (registration N1732) sustained substantial damage when the left main landing gear wheel fractured during landing rollout at Castroville Municipal Airport (CVB), Castroville, Texas. The pilot, who was also the owner and builder, was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight conducted under 14 Code of Federal Regulations Part 91.
Pilot Account
The pilot reported making a normal, 3-point landing on runway 15. During the landing rollout, the airplane began to vibrate, and the left wing dropped toward the asphalt runway. The airplane then veered sharply to the right, departed the runway onto level grass, and flipped over. In addition to the fractured left main landing gear wheel, the rudder and the upper right wing spars were substantially damaged. The left main landing gear and propeller were also damaged.
Wheel Examination
According to the pilot, the Azusa 8-inch wheel had accrued only 11.4 hours since installation and had experienced approximately 15 landing cycles at the time of the accident. At the request of the National Transportation Safety Board Investigator-in-Charge (NTSB IIC), the pilot sent the fractured wheel to the NTSB Materials Laboratory for examination. Examination of the fractured sections revealed a matte gray and rough appearance consistent with overstress fracture of cast aluminum alloy. No evidence of preexisting cracks was observed.
Weight Considerations
According to the Azusa Engineering website, the company manufactures wheels for small recreational and industrial vehicles, including go-karts, mini-bikes, and ultralight aircraft (aircraft with an empty weight of less than 254 pounds per Federal Aviation Regulation Part 103). N1732 weighed about 954 pounds at the time of the accident, a weight that would have required wheels with a higher loading capability than those intended for ultralight aircraft.
When asked how the accident could have been prevented, the pilot stated, "I should have used a different wheel manufacturer!"