WPR22LA015

The pilot stated that the departure started normally but that, after becoming airborne, the airplane controls were not responding to his inputs as expected. The airplane continued to pitch up in a nose-high attitude and he was unable to push the control yoke forward, which he described as feeling like he was “stretching” cables with forward pressure. With the airplane’s pitch uncontrollable, he elected to make a rapid maneuver toward an unpopulated area. The airplane descended into trees; after coming to a stop, a fire erupted. A postaccident examination of the flight control system revealed no definitive evidence of preimpact mechanical malfunctions or failures. Because the elevator system was extensively damaged and was partially consumed by fire, the investigation was not able to determine the cause of the pitch control anomaly. The airplane’s weight and center of gravity (CG) could not be confirmed. The burned remains of items found in the airplane could not be identified and the location of those items at impact could not be confirmed.

On October 14, 2021, about 1600 Pacific daylight time, a WSK Mielec AN-2TD, N857PF, was substantially damaged when it was involved in an accident near Wilton, California. The pilot and one passenger sustained serious injuries and the other two passengers sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot stated that he configured the airplane for takeoff and had flaps down and the elevator trim was neutral. The departure started normally but, after becoming airborne, the airplane controls were not responding to his inputs as expected. The airplane continued to pitch up in a nose-high attitude and he was unable to push the control yoke forward, which he described as feeling like he was “stretching” cables with forward pressure. The pilot set the electric trim to full nose-down but it had no effect. With the airplane’s pitch uncontrollable, he saw an open area and elected to make a rapid maneuver toward the area. He added full left rudder and aileron and the airplane banked left. The airplane descended into trees; after coming to a stop, a fire erupted. The back door would not open due the deformation of the airframe so he broke a front window. The pilot and passengers all climbed out the window and the airplane continued to burn. There were two witnesses located at the airport that took videos of the airplane departing. One video showed the airplane just prior to the takeoff roll. The tailwheel is positioned backward and, as the airplane starts the roll, the tailwheel swivels and the airplane moves to the right of the runway (see Figure 1 below). Figure 1: The Airplane Starting the Takeoff Roll The airplane then veered to the left of the runway and became airborne shortly thereafter. In the approximate 10 seconds that followed, the airplane pitched up at an increasingly higher and higher angle-of-attack. The airplane then made a sharp left turn and goes behind the trees as it descends (see Figure 2 below). Figure 2: The Airplane Airborne The ground track, ground speed, altitude, angle of attack and roll angle of an airplane that crashed shortly after takeoff were estimated based on a video recorded with a handheld phone. The ground speed of the airplane went as low as 19 knots shortly after it started a left turn and a rapid descent toward ground impact. At that time, the airplane reached its maximum above ground level (AGL) altitude of 170 feet and the angle of attack of its wings was estimated to be 22.5º. Engine speed, estimated via spectrum analysis of sound recorded by two cameras, was 2150 rpm several seconds after liftoff and 2200 rpm when the airplane was already descending toward ground impact. The specified engine speed at takeoff for the WSK Mielec AN-2TD is 2200 rpm. A postaccident examination of the flight control system revealed no evidence of preimpact mechanical malfunctions or failures. The elevator system was extensively damaged and was partiallyconsumed by fire. The No. 5 lower pulley gang was found loose in the wreckage with its cover still attached; the No. 5 upper pulley gang had the elevator cables passing through it. The No. 9 pulley gang has an s-hook attached, which appeared to be a tie down for item in the airplane. There were several markings and abrasions on the cable lengths consistent with rubbing or abrasions. The elevator bellcrank remained intact, with all four elevator cables connected to their respective arms. Control continuity was maintained from the bellcrank to the elevator control surfaces. The airplane’s weight and center of gravity (CG) could not be confirmed. The burned remains of items found in the airplane could not be identified and their location at impact could not be confirmed. The pilot estimated that the airplane was loaded about 1,000 pounds below the maximum gross weight. He had it loaded with two coolers, three motorcycles and camping gear. He had strapped all the items in place and did not believe they shifted during rotation.