FTW98LA160

The control rod for the pilot's aileron control separated during takeoff, initial climb, after the pilot heard a 'loud pop'. The pilot elected to land straight ahead, using rudder inputs for directional control. The airplane became airborne and then 'began to drift left of centerline.' Examination of the aircraft revealed a push-pull rod for aileron control was found separated at the connecting point to the bellcrank assembly, behind the left control yoke. Metallurgical examination of the rod disclosed fracture surfaces were rough and had a matte appearance along a shear plane. The rod exhibited bending deformation adjacent to the fracture. According to the metallurgist, these features are typical of an overstress separation. No evidence of pre-existing cracks, such as fatigue, was found.

On March 26, 1998, at 1530 central standard time, an Aero Commander 100 airplane, N5530M, was substantially damaged during a forced landing following a failure in the flight control system, during the initial climb from the Fort Worth Meacham International Airport, Fort Worth, Texas. The airplane was owned and operated by a private individual. The pilot, sole occupant, received minor injuries. Visual meteorological conditions prevailed for the Title 14 CFR Part 91 personal flight for which a flight plan was not filed.

The pilot reported the following events in the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2). The airplane was positioned for take off from runway 16. The airplane became airborne and then "began to drift left of centerline." The pilot stated that he was making control inputs to bring the airplane back to the centerline at 100 feet above ground level, when he heard a "loud pop." He realized that the airplane was no longer responding to aileron control inputs. The 308 hour pilot was able to maintain directional control using rudder inputs and landed on grassy terrian, on airport property.

The owner of the airplane stated that he was not aware of any maintenance performed on the aileron control system prior to the accident.

An FAA inspector reported that the propeller was bent. The nose landing gear was bent rearward into the airframe. The left wing flap, aileron and wing tip were structurally damaged. A push-pull rod for aileron control was found separated at the connecting point to the bellcrank assembly, behind the left control yoke.

The fractured aileron push-pull rod was sent to the NTSB Materials Laboratory in Washington, D.C., for examination. The fracture surfaces were observed to be rough and had a matte appearance along a shear plane. The rod exhibited bending deformation adjacent to the fracture. According to the metallurgist, these features are typical of an overstress separation. No evidence of pre-existing cracks, such as fatigue, was found.

At the time of the accident the Fort Worth International Airport was reporting the following weather conditions; clear skies, visibility 10 miles, and winds from 160 degrees at 23 knots with gusts to 37 knots.