Amateur-built Super Koala N220FF accident near Hazen, North Dakota

Probable cause

The airplane owner's and mechanic's improper rigging and cable tension of the aileron control system, which resulted in a loss of control during takeoff.

NTSB analysis

The airplane owner and a mechanic had reassembled the airplane's wings and re-rigged the flight controls; the pilot had subsequently been having trouble with aileron control during test flights. The accident flight was the fourth test flight of the day to diagnose and fix the issue. During takeoff, the airplane "quickly" became airborne and began to roll to the left about 15 ft above the ground. The pilot applied full right aileron; however, the airplane continued to roll left and descend, and the airplane impacted the ground in a left-wing-low attitude, resulting in substantial damage to the left wing spar, bottom fuselage, cowling, engine, landing gear, and firewall.

Postaccident examination of the airplane revealed improper rigging of the ailerons. The improper rigging and improper aileron cable tensions most likely resulted in a loss of aileron control during takeoff.

Text from the NTSB. Open the NTSB docket for CEN19LA219 for the full record.