N1839Z

HISTORY OF FLIGHTOn August 5, 2016, about 1340 Alaska daylight time, a Cessna 210-5 airplane, N1839Z, and a turbine-powered, tailwheel/ski-equipped, de Havilland DHC-2T (Beaver) airplane, N30CC, collided midair while landing at Wasilla Airport (PAWS), Wasilla, Alaska. The certificated flight instructor and student pilot on board the Cessna sustained minor injuries, and the commercial pilot and passenger on board the de Havilland were not injured. Visual meteorological conditions prevailed in the area at the time of the accident. The Cessna was registered to Flying High, LLC, and it was operated by the student pilot under the provisions of Title 14 Code of Federal Regulations (CFR) Part 91 as an instructional flight. The Cessna departed Merrill Field Airport (PAMR), Anchorage, Alaska, about 1230. The de Havilland was privately owned, and it was operated by the pilot under the provisions of 14 CFR Part 91 as a personal flight. The de Havilland departed Leisurewood Airstrip (9AK6), Wasilla, Alaska, about 1340. Neither airplane was operating on a flight plan.

The instructor on board the Cessna stated that he and the student departed from PAMR to conduct basic instrument flight training before proceeding to PAWS to practice landings. He said that, after arriving at PAWS, the student completed three successful stop-and-go landings on runway 4 while using the published right traffic pattern. He added that he was using the airport's common traffic advisory frequency (CTAF) of 122.80 MHz to announce their positions and intentions throughout the series of stop-and-go landings. The Cessna had two communication radios installed and the instructor and student reported that they utilized the Narco COM IIA radio while at PAWS, due to the presence of static when the Garmin GNS 430 radio was operated. The instructor stated that, during the accident landing, just as the student began the landing flare, there was a sudden loud noise, and the airplane abruptly nosed down. The airplane's nose subsequently impacted the runway. The instructor reported that neither he nor the student heard or saw the other airplane before the collision. The instructor additionally reported that the airplane's landing and navigation lights were on at the time of the accident.

The pilot of the de Havilland stated that he and his passenger were en route to PAWS to get fuel before continuing to Healy, Alaska. He stated that, after departing from 9AK6, which was located about 5 miles northwest of PAWS, he conducted a straight-in final approach for landing on runway 4. He further stated that, while on final approach, about 70 ft above ground level (agl) over the runway threshold, the Cessna overtook the de Havilland from directly above, impacting the propeller. Following the impact with the Cessna, the pilot continued the approach and landed on runway 4. The pilot was able to maintain control and maneuver the airplane off the runway to avoid impacting the Cessna. The de Havilland subsequently departed the left side of the runway and came to rest in about 5 ft high vegetation on sloping terrain. The pilot stated that he used the CTAF before and after entering the straight-in final for runway 4 at PAWS, announcing his positions and intentions. The pilot reported that neither himself nor the passenger heard or visually acquired the Cessna before impact. The pilot additionally reported that the airplane's landing and navigation lights were on at the time of the accident. AIRCRAFT INFORMATIONBoth airplanes were equipped with the required communication equipment for the airspace in which they were operating. Neither airplane was equipped with an automatic dependent surveillance – broadcast (ADS-B) system, nor was either airplane required to be equipped with such a system.

Cessna

The fixed-gear, high-wing, single-engine airplane was manufactured in 1962. The airplane was configured with seating for 2 pilots and no passengers. The airplane was powered by a Continental IO-470 reciprocating engine. The airplane was white with light blue and dark blue accent lines, white wings, a chrome propeller spinner, and a black 2-blade McCauley propeller.

De Havilland

The tailwheel/ski-equipped, high-wing, single-engine airplane was manufactured in 1964. The airplane was configured with seating for 1 pilot and 9 passengers. The airplane was powered by a Pratt & Whitney Canada PT6A-34 turbine engine. The airplane was beige with light blue and grey accent lines, beige wings, a beige propeller spinner, and a black 3-blade Hartzell propeller. AIRPORT INFORMATIONBoth airplanes were equipped with the required communication equipment for the airspace in which they were operating. Neither airplane was equipped with an automatic dependent surveillance – broadcast (ADS-B) system, nor was either airplane required to be equipped with such a system.

Cessna

The fixed-gear, high-wing, single-engine airplane was manufactured in 1962. The airplane was configured with seating for 2 pilots and no passengers. The airplane was powered by a Continental IO-470 reciprocating engine. The airplane was white with light blue and dark blue accent lines, white wings, a chrome propeller spinner, and a black 2-blade McCauley propeller.

De Havilland

The tailwheel/ski-equipped, high-wing, single-engine airplane was manufactured in 1964. The airplane was configured with seating for 1 pilot and 9 passengers. The airplane was powered by a Pratt & Whitney Canada PT6A-34 turbine engine. The airplane was beige with light blue and grey accent lines, beige wings, a beige propeller spinner, and a black 3-blade Hartzell propeller. WRECKAGE AND IMPACT INFORMATIONThe National Transportation Safety Board (NTSB) investigator-in-charge (IIC), three aviation safety inspectors (ASI) from the Federal Aviation Administration (FAA), along with a team of law enforcement officers from the Wasilla Police Department traveled to the accident scene on August 5. The NTSB IIC and the FAA ASIs performed accident site documentation, examined both airplanes, and interviewed the occupants of both airplanes. A postaccident examination of both airplanes, revealed signatures consistent that the initial impact sequence was between the empennage of the Cessna and the propeller assembly of the de Havilland. The substantial damage sustained to the empennage of the Cessna during the impact sequence rendered the airplane uncontrollable and impacted the runway. The de Havilland pilot was able to maintain control and maneuver the airplane off the runway to avoid impacting the Cessna; however, the de Havilland sustained substantial damage from the Cessna impacting its right wing. During the examination of both airplanes at the accident scene revealed that, when power was applied, the 122.80 MHz frequency was displayed for each radio selected in each airplane. The pilots of both airplanes stated that there were no preimpact mechanical failures or malfunctions that would have precluded normal operation of their respective airplanes. ADDITIONAL INFORMATIONOpsVue Track Data

OpsVue track data was used to produce the flight tracks for the two airplanes. OpsVue is a commercially-available program that provides track data in a "mosaic" format, by taking all available surveillance data (ADS-B, radar track data, etc.) received from a transponder-equipped aircraft and applying "smoothing" to achieve the displayed flight track and overlaid onto satellite imagery. The track data showed a convergence of the two airplanes' flight paths about 0.80 miles southwest of the approach end of runway 04 at PAWS before the midair collision over runway 4. The precise altitudes captured for the two airplanes in the OpsVue track data could not be confirmed due to the way in which altitude information is corrected for barometric pressure within the OpsVue system.

Non-Towered Airport Flight Operations

FAA Advisory Circular 90-66B, "Non-Towered Airport Flight Operations," states in part:

The pilot in command's primary responsibility is to see and avoid other aircraft and to help them see and avoid his or her aircraft. Keep lights and strobes on. The use of any traffic pattern procedure does not alter the responsibility of each pilot to see and avoid other aircraft. Pilots are encouraged to participate in "Operation Lights On," a voluntary pilot safety program described in the Aeronautical Information Manual that is designed to improve the "see-and-avoid" capabilities.

It is recommended that airplanes observe a 1,000 ft agl traffic pattern altitude. Large and turbine-powered airplanes should enter the traffic pattern at an altitude of 1,500 ft agl or 500 ft above the established pattern altitude. A pilot may vary the size of the traffic pattern depending on the aircraft's performance characteristics.

The FAA encourages pilots to use the standard traffic pattern when arriving or departing a non-towered airport or a part-time-towered airport when the control tower is not operating, particularly when other traffic is observed or when operating from an unfamiliar airport. However, there are occasions where a pilot can choose to execute a straight-in approach for landing when not intending to enter the traffic pattern, such as a visual approach executed as part of the termination of an instrument approach. Pilots should clearly communicate on the CTAF and coordinate maneuvering for and execution of the landing with other traffic so as not to disrupt the flow of other aircraft. Therefore, pilots operating in the traffic pattern should be alert at all times to aircraft executing straight-in landings, particularly when flying a base leg prior to turning final.

Automatic Dependent Surveillance – Broadcast (ADS-B)

The FAA implemented national ADS-B technology in Alaska. Formerly known as Capstone, the joint industry/FAA program (which includes ground-based stations, satellites, and airplane avionics) currently provides pilots with situational awareness by displaying the air...