Schweizer SGS 2-33A N2045T accident near Erwinna, Pennsylvania

Probable cause

The pilot’s loss of glider control due to improper rigging of the rudder control cables, the mechanic’s inadequate flight control checks following the glider’s most recent annual inspection, and the pilot’s failure to perform a thorough preflight inspection.

NTSB analysis

The glider pilot intended to practice stalls after being towed to an altitude of 3,000 feet mean sea level. Shortly after takeoff, the tow pilot observed the glider yaw left, then right, and then left again. He added that, for most of the tow, the glider appeared to be above the normal tow position with its nose pointed 45 degrees right. About 400 feet above ground level, the glider pilot released the tow line, and the glider turned about 180 degrees left; its right wing then impacted trees, and the glider pitched down and impacted terrain. Postaccident examination of the wreckage revealed that the rudder control cables were rigged backward. The accident flight was the first flight following the glider's most recent annual inspection. Before the annual inspection, the rudder had been removed for repair then re-installed. The mechanic who conducted a flight control check after the annual inspection with assistance from another pilot seated in the cockpit stated that he confirmed movement of the rudder while at the rear of the glider; however, he did not see which pedal the pilot was pushing and did not verbally confirm the corresponding position of the rudder pedals. If the pilot had conducted a thorough preflight inspection, he should have been able to detect that the rudder control cables were rigged backward.

Text from the NTSB. Open the NTSB docket for ERA13LA229 for the full record.