N877DMBeech P35 · 1963

On October 6, 2015, about 1125 mountain daylight time, a Beech P35 (Bonanza) single-engine airplane, N877DM, collided with trees and terrain during cruise flight near Chadron, Nebraska. The airline transport pilot was fatally injured, and the airplane was destroyed. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations (CFR) Part 91 as a personal flight with an instrument flight rules (IFR) flight plan on file. Day instrument meteorological conditions (IMC) prevailed at the accident site. The cross-country flight departed Chadron Municipal Airport (CDR), Chadron, Nebraska, at 1121, and was destined for Alliance Municipal Airport (AIA), Alliance, Nebraska.

According to available flight plan information, on the morning of the accident the pilot filed two flight plans using a direct user access terminal service. The first flight plan was for an IFR flight from North Platte Regional Airport, North Platte, Nebraska, to CDR. The second IFR flight plan was for the accident flight between CDR and AIA. The pilot filed for a direct routing from CDR to BOOKY (a IFR reporting point), then direct to JIVAM (an initial approach fix to AIA), and a cruise altitude of 7,000 ft mean sea level (msl). A fixed-base operator (FBO) employee at CDR reported seeing the airplane arrive on the ramp about 1050. The pilot and passenger subsequently entered the main lobby briefly to use the restroom. The pilot did not use the FBO's weather system before he exited the lobby to the ramp. The FBO employee then observed the pilot walk around the airplane a couple of times before he boarded. The airplane taxied from the ramp about 1110.

According to Federal Aviation Administration (FAA) air traffic control (ATC) track data, the airplane transmitted automatic dependent surveillance-broadcast (ADS-B) position data throughout the flight. A review of the ADS-B data established that the flight departed CDR on runway 11 about 1121:19. After departure, the flight turned right toward the south and proceeded toward the intended destination.

At 1122:16, the pilot established radio contact with Denver Air Route Traffic Control Center (ARTCC) and transmitted, "Eight seven seven delta mike, off of Chadron, I would like to pick up an IFR to, ah, Alliance." The controller replied, "November eight seven seven delta mike, Denver Center roger, ah, stand-by." About 8 seconds later, the controller issued a discrete transponder code, which the pilot correctly acknowledged. At 1122:52, the assigned transponder code updated on the controller's display, which indicated the flight was at 4,200 ft msl and had a ground speed of 145 knots. According to the ADS-B data, the flight proceeded south between 4,200 and 4,400 ft msl and at ground speeds between 135 and 155 knots.

According to recorded ATC transmissions, there were no verbal exchanges between the controller and the pilot during the 2.5 minutes following the issuance of the transponder code; however, the controller was actively communicating with several other aircraft that were operating within his airspace sector. At 1125:16, the ADS-B data indicated that the airplane was at 4,200 ft msl and had a ground speed of 143 knots. No additional track data was received from the airplane. At 1125:23, the controller transmitted, "November eight seven seven delta mike, radar contact nine miles south of the Chadron airport, say altitude." There was no response from the pilot.

According to ADS-B track data and topographic elevation data, the airplane encountered rising terrain as it continued south from the departure airport. The airplane subsequently impacted treetops and a ridgeline about 10 miles south of the departure airport at 4,200 ft msl. The height of the ridgeline was about 900 ft above the departure airport elevation.

According to FAA records, the 61-year-old pilot held an airline transport pilot certificate with single-engine land, multi-engine land, and instrument airplane ratings. The single-engine land rating was limited to commercial privileges. He had been employed as a pilot by American Airlines since 1989 and was type-rated for the Boeing 727, Boeing 737, Boeing 757, Boeing 767, Douglas DC-9, Fokker 100, and Lockheed JetStar. He also held a flight instructor certificate with single-engine, multi-engine, and instrument airplane ratings and a flight engineer certificate for turbojet airplanes. His most recent FAA first-class medical certificate was issued on June 10, 2015, with a limitation for corrective lenses. On the application for his current medical certificate, the pilot reported having accumulated 18,900 hours of total flight experience, of which 400 hours were flown within the previous 6 months.

A current pilot logbook was not located during the investigation; the pilot's most recent logbook entry was dated December 16, 2004. According to an insurance application that was submitted for the operation of the airplane, dated July 24, 2015, the pilot reported having a total flight experience of 19,010 hours, of which 939 hours were flown within the previous year. The pilot reported having flown 195 hours in Beech Bonanza airplanes. According to the insurance application, the pilot's last flight review was completed on June 20, 2015.

The airplane was a 1963 Beech P35 (Bonanza), serial number D-7238. The airplane was a single-engine, low-wing, monoplane of conventional aluminum construction. The airplane was powered by a 285-horsepower, 6-cylinder Continental IO-520-CB-C-BB reciprocating engine, serial number 576182. The engine provided thrust through a constant-speed, three-blade, Hartzell PHC-C3YF-1RF propeller, serial number EE2277A. The airplane was equipped for operations in IMC. The airplane had a maximum allowable takeoff weight of 3,300 pounds and a total fuel capacity of 110 gallons. The FAA issued the airplane a standard category airworthiness certificate on August 6, 1963.

The airplane's recording tachometer was destroyed during the postimpact fire, which precluded a determination of the airplane's total service time at the time of the accident. According to the maintenance logbooks, the last annual inspection was completed on June 11, 2015, at 4,078.86 total airframe hours. At the time of the annual inspection, the engine had accumulated 1,953.08 hours since new and 212.77 hours since the last major overhaul, which was completed on April 29, 2005. The static system, altimeter system, automatic pressure altitude reporting system, and transponder were last tested on March 13, 2015. A postaccident review of the maintenance records found no history of unresolved airworthiness issues.

The National Weather Service (NWS) Surface Analysis Chart issued at 1200 depicted a cold front extending from southern Wyoming east into central Nebraska then northeast into southern Minnesota. The weather station models depicted cloudy skies and a variable surface wind under 5 knots for locations near the accident site. The NWS Area Forecast Discussion issued at 0704 mentioned areas of dense fog and low cloud ceilings near the departure airport and the planned destination. Further, the forecast indicated a slow improvement in weather conditions through the morning hours; however, the conditions were not forecast to improve above marginal visual meteorological conditions (VMC). At the time of the accident, the terminal forecast for CDR indicated a surface wind from 100° at 8 knots, visibility greater than 6 miles, scattered clouds at 700 ft above ground level (agl), and an overcast ceiling at 2,000 ft agl.

At 1053, about 32 minutes before the accident, the CDR automated surface observing system (ASOS) reported: calm wind, 9 miles surface visibility, broken ceiling at 1,500 ft agl and an overcast ceiling at 3,400 ft agl, temperature 14°C, dewpoint 11°C, and an altimeter setting of 30.25 inches of mercury.

At 1153, about 28 minutes after the accident, the CDR ASOS reported: calm wind, 9 miles surface visibility, few clouds at 1,600 ft agl and an overcast ceiling at 3,000 ft agl, temperature 15°C, dew point 11°C, and an altimeter setting of 30.24 inches of mercury.

An individual, who had been working outside near the accident site, reported that throughout the morning there had been light precipitation, mist, fog, and low clouds that obscured the surrounding ridgelines. The individual also recalled that the weather conditions had improved shortly before noon.

A review of weather briefing requests made to official vendors revealed that the pilot had not received a formal weather briefing before departure.

The airplane was a 1963 Beech P35 (Bonanza), serial number D-7238. The airplane was a single-engine, low-wing, monoplane of conventional aluminum construction. The airplane was powered by a 285-horsepower, 6-cylinder Continental IO-520-CB-C-BB reciprocating engine, serial number 576182. The engine provided thrust through a constant-speed, three-blade, Hartzell PHC-C3YF-1RF propeller, serial number EE2277A. The airplane was equipped for operations in IMC. The airplane had a maximum allowable takeoff weight of 3,300 pounds and a total fuel capacity of 110 gallons. The FAA issued the airplane a standard category airworthiness certificate on August 6, 1963.

The airplane's recording tachometer was destroyed during the postimpact fire, which precluded a determination of the airplane's total service time at the time of the accident. According to the maintenance logbooks, the last annual inspection was completed on June 11, 2015, at 4,078.86 total airframe hours. At the time of the annual inspection, the engine had accumulated 1,953.08 hours since new and 212.77 hours since the last major overhaul, which was completed on April 29, 2005. The static system, altimeter system, automatic pressure altitude reporting system, and transponder were last tested on March 13, 2015. A postaccident review of the maintenance records found no history of unresolved airworthiness issues.

The initial impact point was identified by broken treetops that preceded a ridgeline, fractured tree limbs found along the ridgeline, red paint chips found on the ridgeline that matched the paint color of the airplane's lower fuselage, and a portion of the airplane's VHF marker beacon antenna. The initial impact point was about 250 ft south-southeast of the final recorded ADS-B position.

The main wreckage was in a canyon/ravine to the south-southeast of the initial impact point. A wreckage debris path, which initiated from the ridgeline, was about 560 ft long and oriented on a 160° magnetic heading. A large area of burnt ground and vegetation surrounded the main wreckage, which consisted of the fuselage, empennage, right wing, engine, and propeller. A majority of the fuselage, including the cockpit and cabin, had been consumed during the postimpact fire. The left wing had separated from the fuselage and was located further down in the ravine. Flight control cable continuity could not be established due to impact and fire damage; however, all observed separations were consistent with overstress. The flaps were fully retracted. The nose and right main landing gear were fully retracted. The left main landing gear had separated from the wing during the impact sequence. The altimeter's Kollsman window was centered on 30.24 inches of mercury.

The engine remained partially attached to the firewall, and the propeller remained attached to the crankshaft flange. The three-blade propeller exhibited chordwise scratches, spanwise S-shape bends, and a leading edge gouge. One blade exhibited significant blade twisting along its span. Internal engine and valve train continuity were confirmed as the engine crankshaft was rotated. Compression and suction were noted on all cylinders in conjunction with crankshaft rotation. Neither magneto provided a spark when rotated by hand; however, both magnetos exhibited damage consistent with impact and prolonged exposure to fire. The upper spark plugs were removed and exhibited features consistent with normal engine operation. A borescope inspection of each cylinder did not reveal any anomalies with the cylinders, pistons, valves, or valve seats. The vacuum pump produced suction when rotated by hand. The mechanical fuel pump did not rotate freely by hand; however, further disassembly revealed thermal damage to the internal pump components. The fuel pump vanes and drive coupling were not fractured. The fuel metering unit inlet screen was clear and free of any obstructions. The postaccident examination did not reveal any anomalies that would have precluded normal engine operation during the flight.

According to available ATC information, the pilot had not received an IFR clearance and, therefore, was still operating under VFR when the airplane impacted rising terrain at 4,200 ft msl. According to federal regulations, the Aeronautical Information Manual (AIM), and FAA Order 7110.65 (Air Traffic Control), a pilot operating under VFR is responsible for terrain, obstacle, and cloud clearance until reaching the minimum en route altitude (MEA) or the minimum IFR altitude (MIA). The MEA is the lowest published altitude between radio navigation fixes that assures acceptable navigational signal coverage and meets obstacle clearance requirements between those fixes. However, any flight segment not on a published airway or route, such as the direct routing used on the accident flight, the MIA is 1,000 ft above the highest obstacle within a horizontal distance of 4 nautical miles (nm) from the course to be flown in a non-mountainous area. The departure airport and accident site were in a designated non-mountainous area. According to ATC documentation, the MIA was 6,000 ft msl over the departure airport and increased to 6,300 ft msl about 10 nm south of the airport.

According to the FAA Terminal Procedures Publication, the departure airport had non-standard takeoff minimums for runway 11 (a climb to 4,800 ft msl at 240 ft per nm if departing in IMC, or 1,200 ft agl ceiling and 3 sm visibility if departing in VMC). Although adherence with takeoff minimums and departure procedures are not required for 14 CFR Part 91 operations, the AIM encourages their use to ensure obstacle and terrain clearance.

A review of available ATC information confirmed that the flight had received normal services and handling. A transcript of the voice communications recorded during the flight are included in the docket materials associated with the investigation.

The departure airport was equipped with a remote communication outlet (RCO) that provided a radio link to Columbia Flight Service Station; however, on the day of the accident, a notice to airman (NOTAM) indicated that the RCO was out of service. A RCO is routinely used by pilots to obtain an IFR clearance while on the ground. If a RCO is out of service, a pilot can telephone a flight service station to obtain an IFR clearance or, if the weather conditions permit, they can choose to depart under VFR and obtain an IFR clearance when airborne.

The Regional West Medical Center, located in Scottsbluff, Nebraska, performed an autopsy on the pilot at the request of the Dawes County Attorney. The cause of death was attributed to multiple blunt-force injuries sustained during the accident. The FAA's Bioaeronautical Sciences Research Laboratory, Oklahoma City, Oklahoma, performed toxicology tests on specimens obtained during the autopsy. The test results were negative for carbon monoxide, ethanol, and all tested drugs and medications.