DEN01LA034

As the airplane made a full flap approach to the runway, the pilot 'felt a bump,' the right flap retracted, and the airplane rolled abruptly to the right. The pilot added full power and left aileron but it had no effect. The airplane drifted off the right side of the runway, dragging the wing tip, then cartwheeled and nosed into the ground. Postaccident inspection revealed the right hand flap rod (p/n F-659) had failed, causing a split flap condition. The failed actuator rod was made of aluminum tubing threaded at each end. The pilot said, 'Wall thickness at the threaded ends is thin,' and the part should be made of steel. Vans Aircraft, Inc., said 'the failure was associated with poor workmanship rather than materials defect or structural design...the original builder had not enlarged the hole required in the fuselage large enough to prevent the rod from 'scraping' during flap extension. The continued scraping had eventually worn away the entire side of the rod and resulted in total failure.'

On December 24, 2000, approximately 1630 mountain standard time, a Barackman Vans RV-6, N3891P, was substantially damaged when it collided with terrain while landing at the Springfield, Colorado, Municipal Airport. The private pilot and his passenger were not injured. Visual meteorological conditions prevailed, and no flight plan had been filed for the personal flight being conducted under Title 14 CFR Part 91. The flight originated from Santa Fe, New Mexico, approximately 1500.

According to the pilot's accident report, he and his passenger were en route from Phoenix, Arizona, to Dodge City, Kansas, with a refueling stop at Santa Fe, New Mexico. While the airplane was being refueled, he checked the weather and learned that VFR conditions at Dodge City and Garden City were expected to deteriorate. After departing Santa Fe, marginal VFR conditions were encountered and the decision was made to divert to Springfield, Colorado. As the airplane made a full flap approach to runway 17, the pilot "felt a bump," the right flap retracted, and the airplane rolled abruptly to the right. The pilot added full power and left aileron but it had no effect. The airplane drifted off the right side of the runway, dragging the wing tip, then cart wheeled and nosed into the ground.

Post accident inspection revealed the right hand flap rod (p/n F-659) had failed, causing a split flap condition. The pilot noted that the failed actuator rod was aluminum tubing threaded at each end. Wall thickness at the threaded ends is "very thin. I feel this part should be made of steel," he wrote.

Vans Aircraft, Inc., was contacted with the details of this accident. According to the company's general manager, "the failure was associated with poor workmanship rather than materials defect or structural design...the original builder had not enlarged the hole required in the fuselage large enough to prevent the rod from 'scraping' during flap extension. The continued scraping had eventually worn away the entire side of the rod and resulted in total failure."