Accident Overview
A Cessna 208B airplane collided with a powered paraglider during cruise flight at 5,000 feet mean sea level (msl) in Class E airspace. Video evidence indicated that the powered paraglider operator impacted the Cessna’s right wing leading edge, outboard of the lift strut attachment point. The outboard 10 ft of the Cessna’s right wing separated during the collision. The Cessna subsequently impacted terrain at high vertical speed in a steep nose-down and inverted attitude. The powered paraglider operator was found separated from his seat-style harness. The paraglider wing, harness, and emergency parachute were located about 3.9 miles south of the Cessna’s main wreckage site.
Sequence of Events
Based on video evidence and automatic dependent surveillance-broadcast (ADS-B) data, the Cessna and the powered paraglider converged with a 90° collision angle and a closing speed of about 164 knots. About 8 seconds before the collision, the powered paraglider operator suddenly turned his head to the right. About 6 seconds before the collision, the powered paraglider maneuvered in a manner consistent with an attempt to avoid a collision with the converging Cessna.
Pilot Actions and Visual Detection
Research indicates that about 12.5 seconds can be expected to elapse between the time a pilot sees a conflicting aircraft and the time an avoidance maneuver begins. Additionally, research suggests that general aviation pilots may only spend 30–50% of their time scanning outside the cockpit. About 8 seconds before the collision, when the powered paraglider operator’s head suddenly turned to the right, the Cessna would have appeared in his peripheral view, where visual acuity is very poor. There would have been little apparent motion because the aircraft were on a collision course.
Under optimal viewing conditions, the powered paraglider may have been recognizable to the Cessna pilot about 17.5 seconds before the collision. However, the Cessna pilot did not attempt to maneuver his airplane to avoid a collision. Further review revealed that the powered paraglider was superimposed on a horizon containing terrain features, creating a complex background. Research suggests that the powered paraglider in a complex background may have been recognizable about 7.4 seconds before the collision, but limited visual contrast against the background may have further reduced visual detection to 2–3 seconds. Thus, it is likely that the Cessna pilot did not see the powered paraglider with sufficient time to avoid the collision.
Aircraft Equipment and Communication
The Cessna was equipped with a transponder and an ADS-B OUT transmitter, making the airplane visible to the air traffic control system. Operation of the powered paraglider in Class E airspace did not require two-way radio communication with air traffic control, the use of a transponder, or an ADS-B OUT transmitter; therefore, it was not visible to air traffic control. Neither the Cessna nor the powered paraglider were equipped with ADS-B IN technology, cockpit display of traffic information, or a traffic alerting system.
Toxicology Findings
Postmortem toxicological testing detected the prescription antipsychotic medication quetiapine, which is not approved by the Federal Aviation Administration, in the Cessna pilot’s muscle specimen, but the test results did not provide a sufficient basis for determining whether he was drowsy or otherwise impaired at the time of the collision. Testing also detected ethanol at a low level (0.022 g/dL) in the Cessna pilot’s muscle specimen, but ethanol was not detected (less than 0.01 g/dL) in another muscle specimen. Based on the available results, some or all of the small amount of detected ethanol may have been from postmortem production, and it is unlikely that ethanol effects contributed to the accident. The Cessna pilot likely did not have sufficient time to see and avoid the powered paraglider regardless of any potential impairment by quetiapine, and it is unlikely the effects of quetiapine or an associated medical condition contributed to the accident.