NTSB Factual Report

On December 30, 2014, about 1320 eastern standard time, an experimental amateur-built Zenith Zodiac CH 650, N419PE, was substantially damaged when it impacted terrain while on approach to landing to St. Lucie County International Airport (FPR), Fort Pierce, Florida. The private pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the local personal flight, which was conducted under the provisions of Title 14 Code of Federal Regulations Part 91 and originated at 1200.

After conducting a preflight inspection the pilot stated that he closed the canopy and pushed both locking handles forward until they stopped. After conducting a runup check of the engine, he verified that both of the latches remained closed, then departed on the accident flight. On return to the departure airport he entered the traffic pattern with the intention of performing several touch-and-go landings. After setting the flaps to 10° and trimming the airplane, the pilot turned onto final approach to runway 28, at an airspeed of 75 knots. At a height of about 50 ft, the cockpit canopy opened, and the airplane suddenly pitched nose down. The pilot responded by "pulling on the stick" and increasing engine power, but found the elevator control to be ineffective. He also noted that the canopy had opened about 3 inches. The airplane subsequently impacted the ground in a nose down attitude.

Federal Aviation Administration (FAA) inspectors examined the airplane following the accident and found that the forward portion of the fuselage had been substantially damaged during the impact.

According to FAA records, the pilot held a private pilot certificate with ratings for airplane single-engine land. His most recent FAA third class medical certificate was issued on July 2, 2013. The pilot reported 767 total hours of flight experience, of which 2 hours were in the same make and model as the accident airplane. His most recent flight review was dated November 7, 2013.

The single-engine, two-seat, kit-built, low-wing, airplane was issued a special airworthiness certificate on August 15, 2014. It was powered by a Lycoming YIO-233-B2A, 115-horsepower engine, equipped with a Sensenich 2 blade propeller assembly. The most recent condition inspection was completed on August 29, 2014. At the time of the accident, the airframe total time was 14 hours.

Examination of plans and photographs of an exemplar airframe provided by the airframe kit manufacturer revealed that the airplane's canopy latch system (figure 1) consisted of a middle canopy lock tube located behind the two cockpit seats that extended to the fuselage on both sides. A locking handle (black lever located at shoulder level) extended between the seats, which would lock the canopy when rotated to the locked position. The middle canopy lock tube was attached by linkage to a canopy latch assembly located on the outboard aft cockpit where the canopy met the airframe near the back of the cockpit. The latch assembly would rotate forward over a bolt positioned on the canopy frame to lock it into place. The canopy could be latched and locked from the outside by means of a handle located on the left side of the fuselage just below and aft of the canopy.

Postaccident examination of the accident airplane revealed that in addition to the above described mechanism, the latch assemblies on both the left and right side of the cockpit had been fitted with red handles (figure 1 inset). Examination of the kit manufacturer's plans revealed that this handle was not a part of the original latching mechanism design.

Postaccident functional testing of the accident airplane's canopy revealed that the when closing the canopy, the edge repeatedly caught on the frame of the cabin in several locations, preventing it from seating correctly in the closed position. To ensure the canopy was fully closed and not catching on the frame, it had to be pulled outward towards the wing and manipulated into the closed position. From inside the cockpit, it was difficult to close the canopy fully without assistance from the outside, since it would catch on the frame. The canopy could not be latched using the locking lever (black handle) from inside the cockpit. When operating the latch by the red handle, no audible or tactile feedback (e.g., a "click") was provided when the latch was engaged. When both latches were pushed to their respective forward-most positions, it appeared that their respective bolts had not fully seated into their recesses.

NTSB Probable Cause

The inadequate modification of the airplane’s canopy latching mechanism, which resulted in the inadvertent opening of the canopy while on final approach to land and a subsequent loss of pitch control.