Czech Sportplanes Sro DYNAMIC N595DY accident near Palm Springs, California

Probable cause

Inadvertent opening of the airplane canopy during the landing approach in a downdraft, which resulted in a rapid descent and hard landing.

NTSB analysis

The pilot was landing the light sport airplane at the termination of a 2 1/2-hour-long flight. During final approach, the airplane encountered a strong downdraft and the canopy extended to the full up position. The pilot was unable to reach the canopy handle to close it, and the airplane landed hard, likely due to the drag created by the open canopy. The left horizontal stabilizer and left aileron were substantially damaged.

Postaccident examination revealed that the canopy latch did not always fully engage in the cabin frame during the closing operation; the latching pin would sometimes extend about 5 millimeters short of the 15 millimeters of full travel. Thus, it is likely that the pilot's encounter with a strong downdraft could have caused the canopy to flex and open if the latch was not fully engaged.

In 2008, the airplane's manufacturer issued a Mandatory Service Bulletin requiring a revision to the flight manual. The revision stated that, if the canopy locking pin is not securely latched during the pre-flight inspection, the canopy could open in flight. The revision included operational updates specifying procedures for securing an inadvertent canopy opening during various phases of flight. The procedures stated that provided the airplane is flown in a straight and level attitude, the canopy will only partially extend, and could be retracted and locked by hand. The procedures warned that, during uncoordinated flight, the canopy will extend to the full open position, acting as an airbrake and resulting in an excessive descent.

Text from the NTSB. Open the NTSB docket for WPR11LA119 for the full record.