N111KD

On August 29, 2000, approximately 1100 mountain daylight time, a Maule MX-7-235, N111KD, sustained substantial damage when it departed the side of the runway during landing at Jeffco Airport (BJC), Broomfield, Colorado. The private pilot, the sole occupant in the airplane, was not injured. The pilot was operating the airplane under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the cross-country personal flight that originated 1 hour 40 minutes before the accident. No flight plan had been filed.

The pilot reported that during landing roll on runway 29L, the left wing "suddenly lifted." He said the aircraft ground looped to the right and departed the right side of the runway. According to airport authorities, the left main landing gear collapsed. The left wing aft spar, the furthest outboard rib, and the left side of the fuselage were damaged.

The airport authorities assisted the pilot in unloading a "large cooler" of elk meat. Documentation provided by the pilot indicates that the airplane was within weight and balance limitations.

The pilot submitted a letter to the Investigator-In-Charge (IIC) suggesting that wake turbulence from a preceding landing aircraft may have upset his airplane. The recorded wind at the time of the accident was 350 degrees at 10 knots, or a 9 knot direct crosswind. The Aeronautical Information Manual (AIM) states that aircraft wingtip vortices move horizontally, near the ground, at 3 knots. The IIC calculated that runway 29L would have been cleared of all wingtip vortexes in 5 to 8 seconds.

The pilot stated on his accident report that "more diligence on landing, quicker response to divergence of [the] aircraft" could have prevented the accident.