N4459R

HISTORY OF FLIGHTOn June 27, 2013, about 1020 mountain daylight time, a Cessna 172M, N4459R, was substantially damaged when it struck powerlines and terrain during an attempted emergency landing on a road near Birdseye, Utah. The airplane was owned and operated by IMSAR Aviation, a wholly owned subsidiary of IMSAR, of Springville, Utah. The commercial pilot was seriously injured, and the required crewmember received fatal injuries. The radar equipment test flight was operated under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the local flight.

According to representatives of IMSAR, the airplane was one of two Cessna 172 airplanes used as platforms for the development and testing of airborne radar systems. The airplanes were based at Spanish Fork-Springville airport (U77), Springville, Utah. IMSAR employed one full time pilot, and occasionally utilized the services of contract pilots. On the morning of the accident, the IMSAR pilot was operating the other company airplane, and a contract pilot was operating the accident airplane. The mission plan was to fly predetermined tracks and/or orbits at a location about 16 miles south of U77, at an altitude of about 8,000 feet, for several hours.

The engine start, taxi, run-up, and takeoff were uneventful. The pilot flew toward the assigned test location of Birdseye via the Spanish Fork Canyon. The IMSAR-required test altitude for this particular flight was 2,500 feet above ground level. The airplane arrived on station over Birdseye and conducted the straight-line track portion of the test program, which took about 2 hours. The pilot then began flying some 360-degree orbit (circling) tracks, remaining near the Birdseye area.

After flying several orbits, the test engineer told the pilot that he smelled smoke. The pilot discontinued the orbiting, and began looking for the smoke and its source. He noticed smoke wafting from under the front seats toward the front of the aircraft, and opened both windows and one vent to evacuate the smoke. He then looked over his right shoulder, towards the rear of the airplane, and observed an open flame about 8 inches high and 4 inches in diameter. The flame was situated on top of one of the test equipment components that were located behind the front seats.

The pilot made the decision to land as soon as possible, and after visually scanning the region below, he decided that landing on the road was the best option. The pilot maneuvered the airplane for a northbound, right-hand downwind leg, and simultaneously broadcast a "mayday" communication on the emergency frequency of 121.5 MHz. He received a response almost immediately from an overflying airliner, and briefly advised the airliner of the situation, providing airplane registration number, location, nature of the problem, and his intentions. The pilot then ceased communicating on the radio, and focused on the landing. He configured the airplane for landing, and set up to land to the south on the road. Just before the planned touchdown, when the airplane was about 30 feet above the road, the pilot visually detected a powerline that was suspended above the road and in his path, and pulled up in an attempt to overfly it. The airplane struck that wire, and then struck other powerlines and terrain. There was no post impact fire. Passers-by came to the aid of the pilot, and contacted emergency services to notify them of the accident. PERSONNEL INFORMATIONPilot

Federal Aviation Administration (FAA) records indicated that the pilot held commercial pilot and flight instructor certificates with single-engine land ratings. According to information provided by the pilot, he had approximately 2,528 total hours of flight experience, which included approximately 2,088 hours in single-engine airplanes, and 20 hours in the accident airplane make and model. He had most recently flown the accident airplane about 1 month prior. His most recent flight review was completed in November 2012, and his most recent FAA first-class medical certificate was issued in May 2013.

According to the pilot, he was a part-time contract pilot who began flying for IMSAR in early February 2013. At that time, as part of his orientation, he was instructed on what IMSAR-related equipment was already installed in the airplane, what equipment would typically be brought to the airplane from the IMSAR office by test personnel, and "generally how to mount and connect that equipment."

His most recent flights for IMSAR were on May 31, 2013, and one of those flights was about a 1-hour familiarization flight in the accident airplane; that familiarization flight was the pilot's first flight in that particular airplane. That flight was "completely normal" and "uneventful," and the pilot "found nothing about the aircraft or the flight to be unusual, particularly challenging or bothersome."

The pilot reported that IMSAR equipment test flights always included 2 persons; 1 pilot and 1 engineer/observer. The pilot was responsible for flying the airplane to the test area, and executing the designated flight test ground tracks, which were depicted on the panel-mounted guidance equipment. The pilot stated that the engineer/observer generally had the responsibility to either perform or assist with the equipment mounting and hookup, and that specific operations of the equipment were the responsibility of the engineer/observer.

The pilot incurred serious impact injuries, but no fire- or thermal-related injuries.

Test Engineer

The test engineer was an engineering employee of IMSAR. He was not a pilot. According to documentation provided by IMSAR, he had flown as the test engineer in the accident airplane twice on June 14, and once on June 18. The durations of those flights were 4.0, 2.5, and 2.0 hours, respectively. The pilot for all three of those flights was the IMSAR chief pilot.

The test engineer did not incur any thermal injuries; his death was impact-related. AIRCRAFT INFORMATIONFAA information indicated that the airplane was manufactured in 1974 as Cessna serial number 17263201, and was equipped with a Lycoming O-320 series engine. The airplane was purchased by IMSAR Aviation in February 2013, and modified for mounting and testing of the radar equipment. IMSAR Aviation utilized the services of an independent FAA mechanic with an inspection authorization rating for some of the modifications. The airplane was registered to IMSAR in the restricted category.

At the time of the accident the airplane had accumulated approximately 2,111 hours total time in service. Its most recent annual inspection was completed on June 2, 2013, and it had accumulated about 13 flight hours since that inspection.

Review of the airplane flight logs indicated that the airplane was not operated during the period from February 23, 2013, to May 30, 2013, inclusive. The airplane flew one flight of 1.0 hours on May 31. It then flew two flights on June 14, and one each on June 17 and June 18. The next flight was the accident flight. The respective durations of those five pre-accident flights were 1.0, 4.0, 2.5, 1.7, and 2.0 hours, for a total time of 11.2 hours.

The certification basis for the airplane required that the cabin furnishings, including the floor carpet, be "flame resistant." The regulations and certification criteria defined a "flame resistant" material as material "which will not support combustion to the point of propagating, beyond safe limits, a flame after the removal of the ignition source." The certification basis did not include smoke, fume, or particulate criteria.

There was no fire extinguishing equipment on board, nor was a fire extinguisher FAA- or IMSAR- required equipment for the flight. FAA requirements for general aviation aircraft certificated subsequent to the certification of the accident airplane mandated equipping those aircraft with fire extinguishers. METEOROLOGICAL INFORMATIONThe 0955 automated weather observation at an airport located about 20 miles north of the accident site included variable wind at 3 knots, visibility 15 miles, clear skies, temperature 26 degrees C, dew point 9 degrees C, and an altimeter setting of 30.25 inches of mercury.

According to astronomical data from the National Oceanic and Atmospheric Administration, at the accident location about the time of the accident, the sun's azimuth was about 98 degrees from true north, and its elevation was about 47 degrees above the horizon. AIRPORT INFORMATIONFAA information indicated that the airplane was manufactured in 1974 as Cessna serial number 17263201, and was equipped with a Lycoming O-320 series engine. The airplane was purchased by IMSAR Aviation in February 2013, and modified for mounting and testing of the radar equipment. IMSAR Aviation utilized the services of an independent FAA mechanic with an inspection authorization rating for some of the modifications. The airplane was registered to IMSAR in the restricted category.

At the time of the accident the airplane had accumulated approximately 2,111 hours total time in service. Its most recent annual inspection was completed on June 2, 2013, and it had accumulated about 13 flight hours since that inspection.

Review of the airplane flight logs indicated that the airplane was not operated during the period from February 23, 2013, to May 30, 2013, inclusive. The airplane flew one flight of 1.0 hours on May 31. It then flew two flights on June 14, and one each on June 17 and June 18. The next flight was the accident flight. The respective durations of those five pre-accident flights were 1.0, 4.0, 2.5, 1.7, and 2.0 hours, for a total time of 11.2 hours.

The certification basis for the airplane required that the cabin furnishings, including the floor carpet, be "flame resistant." The regulations and certification criteria defined a "flame resistant" material as material "which will not support combustion to th...