History of Flight
On September 6, 2014, about 1202 Pacific daylight time, a Piper PA 25-235, N7117Z, collided with terrain while performing glider tow operations at Warner Springs Gliderport, Warner Springs, California. The airplane was registered to, and operated by, Sky Sailing, Inc., under 14 Code of Federal Regulations Part 91. The airline transport pilot sustained serious injuries and the airplane was substantially damaged. The local flight departed Warner Springs about 1200 with a Schweizer SGS 2-33A glider, N7547, in tow. Visual meteorological conditions prevailed, and no flight plan had been filed.
Tailwind departure operations were in effect from runway 26 due to wind conditions and local topography. The departure procedures required an immediate left turn into the traffic pattern after takeoff, with the landing performed into the wind on the opposing runway. The tow pilot reported launching a series of gliders to Mount Palomar without incident, and that his next tow was for N7547.
The glider pilot indicated via hand signal that he also wanted to fly to Mount Palomar, and the tow was initiated. Quartering left tailwind conditions existed, and the initial ground roll was uneventful. The pair flew in ground effect at 65 mph just before reaching the arrival end of runway 8. The tow pilot reported encountering a slight downdraft as he began a left crosswind turn, but stated this was not unusual. As the turn progressed, he felt the glider slide out of position to the right and above, forcing the tow plane into a nose-down attitude. He stated it was not uncommon for gliders to go out of position at that location, and he was ready to release the glider if the condition worsened. The glider remained out of position as they cleared trees on the crosswind leg, and by the time they turned downwind the glider began another series of diversions as the tow pilot attempted to continue climbing. He reported they were still low on downwind but clear of obstructions. The diversions again became excessive, forcing the tow plane's nose low. The pitch attitude recovered, and he could no longer see or feel the glider at about 200 feet agl. He assumed the glider had released. Shortly after, the tow plane violently yawed left to an extreme nose-low attitude such that his forward view was entirely ground and trees. He stated this was the worst deviation he had experienced as a tow pilot, and realizing the glider was still attached, he pulled the line-release handle. He attempted to recover directional control, but the airplane struck the ground nose and right-wing low.
The glider pilot stated that shortly after rotation, the nose of the glider pitched up, but he quickly rectified the excursion. During initial climb the glider climbed to a high tow position and was forced right by what he believed was the crosswind. He countered with left rudder while attempting to descend, but remained far right as the tow plane began a left crosswind turn. The tow plane appeared below him and close to trees as they turned downwind, and slack developed in the line. He applied right rudder and down-elevator and reached for the line handle in anticipation of early release. He became concerned about his position, but the slack dissipated with a "jolt." The tow plane turned left and slack developed again, more severely. He countered with right rudder and down-elevator; as the line tightened the tow plane rocked back and forth, and he pulled the release handle at about 200 feet agl. He then initiated an uneventful return to land on runway 8. The glider sustained no damage, and neither the pilot nor passenger (rear seat) were injured.
Three witnesses provided corroborating statements. They reported the initial takeoff appeared normal until the first crosswind turn when the glider swung out of position to the right and above the tow plane. As the flight progressed to downwind, the glider became grossly out of position, with one witness reporting that just prior to release the tow line formed a "U" shape as the glider gained on the tow plane.
The glider pilot reported a total flight experience of 1,036 hours in all aircraft, with 56 hours in gliders, 45 of which were in the accident type. He stated he had flown the downwind departure before and discussed the procedures with a flight instructor earlier that day. The manager of the gliderport reviewed his logbooks for currency, and he was cleared to depart.