Zenair Ltd CH 2000 N26ZA accident near Mcallen, Texas

Probable cause

The flight instructor's loss of airplane control while departing in gusting wind conditions that were conducive to low-level wind shear.

NTSB analysis

According to communications with a tower air traffic controller, the flight instructor and student pilot planned on completing four or five takeoffs and landings. The first takeoff attempt was aborted for unknown reasons, and the airplane was taxied back to the beginning of the runway for another takeoff attempt. About eight minutes later, the airplane departed. The tower controller later stated that the made a right turn after departure; the airplane's airspeed appeared low when a wing dropped and the airplane descended straight down. Two other witnesses stated that the airplane appeared to be stopped in the air before it dropped. The airplane impacted in a nose-low and left-wing-low attitude. One propeller blade exhibited damage that was indicative of the propeller turning at impact. A postimpact fire ensued and consumed a majority of the airplane. A postaccident examination did not reveal any preimpact mechanical malfunctions or failures with the airframe or engine that would have precluded normal operation.

A gust front and rain shower were passing through the area about the time of the accident, and the wind conditions were changing. The recorded wind at the time of the accident was from the east at 19 knots, gusting to 25 knots. The gust front likely produced low-level wind shear across the region. The accident is consistent with an aerodynamic stall in gusting wind conditions, which resulted in a loss of control and impact with terrain.

A medical evaluation of the flight instructor revealed that he sustained fractures of both feet, which is indicative of him manipulating the rudder pedals during impact, thus he was likely the pilot flying at the time of the accident.

Text from the NTSB. Open the NTSB docket for CEN15FA362 for the full record.