Aircraft: Cessna 150. Injuries: None. Location: Sully, Iowa. Aircraft damage: Substantial.
What reportedly happened: The pilot and his passenger were taking off on a 2,130-foot turf runway. During the takeoff, the airplane lifted off, remained in ground effect, veered to the left, and then settled back onto the runway crashing into a sign and a tree.
Post-accident examination of the engine revealed that two of the No. 4 cylinder’s three piston compression rings had fractured but remained intact. Since two rings were intact and the third ring was not fractured, compression in the cylinder should not have been substantially reduced.
Post-accident computations of ground roll distance showed that the acceleration achieved during the accident takeoff roll was almost equal to that of the airplane’s expected performance on hard-surface runways, indicating that there was not a substantial decrease in available propulsive thrust at the time of takeoff.
FAA guidance recommends that pilots ensure that runway length is equal to the aircraft manufacturer’s published takeoff or landing distance plus an 80 percent safety margin for takeoffs on a hard surface and double the manual distance for takeoffs on sod.
Probable cause: The pilot’s failure to attain an adequate climb rate during the initial takeoff, resulting in the airplane settling back down and departing the runway. Contributing to the accident was the pilot’s inadequate preflight planning and preparation.
NTSB Identification: CEN11LA366
This May 2011 accident report is provided by the National Transportation Safety Board. Published as an educational tool, it is intended to help pilots learn from the misfortunes of others.