SZD 48 JANTAR STD 2 N456RM accident near Labelle, Florida

Probable cause

The pilot's failure to maintain control of the glider for reasons that could not be determined based on the available evidence.

NTSB analysis

The private pilot assembled his glider for a local flight, and a tow rope from a tow airplane was attached to the glider. According to the tow pilot, the pilot requested to be towed to 3,000 ft above field elevation before release. During the climb out, when the glider was about 200 ft above ground level (agl), the tow pilot noticed that the tow rope had a lot more slack than normal and that the glider was moving around a lot more than usual. The tow pilot started a shallow turn to the right to keep the airplane upwind and "take up the slack in the tow rope," but, during this maneuver, the slack remained in the line. The tow pilot stated that, at 400 ft agl, the glider encountered a thermal and began to climb rapidly while lifting the tail of the tow airplane. The glider released from the tow rope, and the tow pilot continued in straight ahead in level flight to avoid the glider. The tow pilot subsequently noticed that the glider was about 200 ft below the tow airplane in a spin. The glider continued to spin until it impacted the ground.

A review of the data retrieved from the onboard flight data recorder revealed that, when the glider reached an altitude of 400 ft agl, its airspeed was 75 knots. The glider's altitude continued to increase as its airspeed began to decrease. The glider reached a maximum altitude of 485 ft before descending to 472 ft about 6 seconds later. At that time, the airspeed reached its lowest recorded speed, about 55 knots. No other information for the flight was recorded.

Although the glider's lowest recorded speed was above its stall speed, it is possible that the glider entered an inadvertent stall based on the tow pilot's observations of the glider spinning and descending until impact; however, the investigation could not determine the reason for the loss of control.

Text from the NTSB. Open the NTSB docket for ERA18FA128 for the full record.