Cessna 182A N5131D accident near Concord, Wisconsin

Probable cause

The pilot's failure to properly plan for a maximum performance takeoff by not fully addressing the elevated density altitude or the nonstandard runway surface conditions and his failure to properly configure the airplane's flap setting for the accident takeoff.

NTSB analysis

The pilot was attempting to depart from a 1,800-foot-long turf runway at the time of the accident. He noted that the grass was about 4 inches high and the ambient temperature was about 84 degrees F. The pilot stated that takeoff acceleration was slow and, when the airplane did not lift off within 200 feet of the expected point, he decided to abort the takeoff. He subsequently realized that he would not be able to stop the airplane on the remaining runway and intentionally veered to the left to avoid trees. The airplane encountered a soybean field and a small tree during the runway excursion. The pilot reported no mechanical failures or malfunctions with the airplane that would have precluded normal operation. He noted that the airplane weight was near the maximum certificated takeoff gross weight and commented that he should have more closely factored the effect of density altitude on the operation.

The airport elevation was 833 feet, and the associated density altitude was about 2,070 feet. The airplane owner's handbook provided takeoff data applicable to a hard surfaced runway with a 20-degree flap setting. From a hard surface runway, at 2,500 feet mean sea level, an ambient temperature of about 81 degrees F, and calm wind, the expected ground roll would be about 750 feet.

The investigation revealed that the pilot did not configure the airplane for a maximum performance takeoff as specified in the owner's handbook. The pilot attempted the accident takeoff with a 10-degree flap deflection instead of a 20-degree flap deflection, as specified. In addition, available takeoff performance data were only applicable to a hard-surfaced runway; takeoff data were not available for a turf runway. The takeoff from a turf runway and the improper flap setting, as well as the elevated density altitude that day, would be expected to increase the takeoff ground roll.

Text from the NTSB. Open the NTSB docket for CEN13LA503 for the full record.