SEA08LA101

The airplane's canopy partially opened shortly after takeoff, and the pilot elected to return to the airport for landing. When he was about one-half mile from the airport, he inadvertently allowed the airspeed to drop below stall speed (Vs), and the airplane stalled and mushed into the terrain. A postaccident inspection of the latch found it to be fully functional, with no evidence that it would not latch the canopy if the canopy was firmly closed. The latching mechanism is of a spring-loaded self-activating design that automatically slides over the top of a tang attached to the canopy when the canopy is firmly closed by the pilot. The mechanism then remains in the latched position until the pilot moves the release ring into a position that causes the latch to release. The latching mechanism is located about a foot above, and six inches behind, the right shoulder of a pilot sitting in the left seat. In this position the latch is not easily checked visually, thus dictating that the pilot close the canopy firmly, and then push up on the canopy firmly in order to ensure that the latching mechanism has become fully engaged. Discussions with the manufacturer disclosed that since the time that this airplane was manufactured, but prior to this accident, the manufacturer redesigned the airplane canopy latching system. The new design incorporates two latching mechanisms that are located just forward of the pilot on the left and right side fuselage surfaces upon which the canopy rests when closed. The mechanisms are not self-locking, and are instead positive-action latches that must be engaged by the pilot.

On March 31, 2008, about 1100 mountain standard time, a Jihlavan KP 5 ASA Light Sport Aircraft (LSA), N31KP, impacted the terrain during an attempted emergency landing near Marana Regional Airport, Marana, Arizona. The private pilot, who was the sole occupant received minor injuries, and the airplane, which is owned and operated by the pilot, sustained substantial damage. The 14 CFR Part 91 local personal pleasure flight, which departed Marana Regional Airport about two minutes prior to the accident, was being operated in visual meteorological conditions. No flight plan had been filed.

According to the pilot, just after takeoff as the airplane reached an altitude of about 70 feet above the runway, the airplane's canopy became unlatched and partially opened. After the canopy came open, the pilot turned back toward the airport, but because of the difficulty he experienced controlling the airplane with the canopy partially open, he elected to attempt a landing in a nearby open field. According to the pilot, during the final portion of the approach to the open field, the airplane's airspeed became too slow, and it therefore stalled and mushed into the terrain.

An inspection of the canopy latching mechanism by a Federal Aviation Inspector from the Scottsdale Flight Standards District Office determined that the mechanism was fully functional and capable of holding the canopy in the closed position when it was firmly closed. It was further determined that the mechanism was of a spring-loaded self-activating design that automatically slides over the top of a tang attached to the canopy when the canopy is firmly closed by the pilot. The mechanism then remains in the latched position until the pilot moves the release ring into a position that causes the latch to release.

Further investigation by the NTSB Investigator-In-Charge (IIC) determined that the latching mechanism is located about a foot above and six inches behind the right shoulder of a pilot sitting in the left seat of the airplane. In this position the latch is not easily checked visually, thus dictating that the pilot close the canopy firmly, and then push up on the canopy firmly in order to ensure that the latching mechanism has become fully engaged. According to the importer of this model airplane, in addition to checking the security of the canopy by pushing up on it, the pilot normally can hear the latch mechanism click into place when the canopy is closed prior to starting the engine. But, prior to this specific flight, the pilot already had the engine running when he closed the canopy and pushed up on it.

The IIC further determined that since the time that this airplane was manufactured, but prior to this accident, the manufacturer redesigned the airplane canopy latching system. The new design incorporates two latching mechanisms, one each of which is placed just forward of the pilot on the left and right side fuselage surfaces upon which the canopy rests when closed. The mechanisms are not self-locking, and are instead positive-action latches that must be engaged by the pilot.