History of Flight
On December 19, 2012, about 0002 mountain standard time, a Beech B100, registration N499SW, collided with trees near Libby, Montana. Stinger Welding operated the airplane under 14 Code of Federal Regulations Part 91. The non-certificated pilot and one passenger sustained fatal injuries; the airplane was destroyed by impact forces. The cross-country personal flight departed Coolidge, Arizona, about 2025 MST with Libby as the planned destination. Visual meteorological conditions prevailed at the nearest official reporting station, and an instrument flight rules (IFR) flight plan had been filed.
The Federal Aviation Administration reported that the pilot was cleared for the GPS-A instrument approach procedure for Libby Airport (S59), about 7 nm south-southeast of Libby. The pilot acknowledged the clearance at 2353. At 2359, the airplane target was about 7 miles south of the airport; the pilot reported the field in sight and cancelled the IFR flight plan. Recorded radar data indicated a Mode C altitude of 11,700 feet mean sea level, and the beacon code changed from 6057 to 1200.
A track from the FlightAware internet site showed a target at 2320 at 26,000 feet heading toward Libby. The target began descending at 2340:65. At 2359:10 and 11,700 feet, the beacon code changed to 1200. The target continued descending, crossed the airport (elevation 2,601 feet) at 0000:46 at 8,300 feet, then continued north. The last target was at 0001:58 at 5,000 feet, about 3 miles south of Libby and over 4 miles north of the airport.
A police officer reported observing a twin-engine airplane emerge from clouds over Libby about 500 feet above ground level. It turned left and re-entered clouds. The officer thought it was likely heading to the airport; he went but saw no airplane. It was dark but clear at the airport, with about 3 inches of snow on the ground, and stars visible. The rotating beacon was illuminated, but not the pilot-controlled runway lighting. He heard no airplane.
When the pilot did not appear at a company function midday December 18, he was reported overdue. The Prescott, Arizona, Automated Flight Service Station issued an alert notice at 1102 MST; the wreckage was located at 1835.
Personnel Information
Review of FAA medical records showed the 54-year-old pilot first applied for an Airman Medical and Student Pilot Certificate in August 2004, reporting 500 hours total time with 200 hours in the previous 6 months. No alcohol or medication usage was reported, but he was determined red/green color blind.
On June 9, 2010, he reported 925 hours total time with 150 hours in the previous 6 months. He received a third-class medical certificate not valid for night flying or using color signal control.
On May 16, 2012, the pilot received a driving while intoxicated (DWI) citation in Libby.
On an application dated October 16, 2012, he reported 980 hours total time with 235 hours in the previous 6 months, a fail on color vision, a new diagnosis of hypertension, and use of medications. He reported yes to a history of arrest or conviction for DWI. The FAA deferred issuance of the Student Pilot and Medical Certificate, investigating a failure to report within 60 days the alcohol-related motor vehicle action.
The National Transportation Safety Board investigator-in-charge reviewed pilot logbooks from March 21, 2010, to November 4, 2012. Entries indicated 978 hours total time during that period. Time logged in the 90 days before the accident was 34 hours. The logbooks recorded numerous trips to Libby, with three entries in the previous 90 days. The last solo flight endorsement, in a Cessna 340, was signed by a certified flight instructor in August 2011. The logbook contained several entries for flights in IFR conditions.
The chief pilot for the company stated that the accident pilot owned the company and typically arranged for a contract pilot to fly with him in the accident airplane. The chief pilot was available to fly the company's CJ2 jet, but the owner never contacted him for the accident flight.
A contract pilot who flew with the accident pilot on December 16, 2012, reported the airplane was in perfect condition, with no squawks. The pilot used paper charts and an iPad, handled the airplane well, was competent, and understood all systems. The autopilot operated properly during the outbound trip; they used approach mode including vertical navigation. The pilot had no physical complaints or lack of sleep, and fueled the airplane himself.
The passenger was a company employee who was not a pilot.
Aircraft Information
The airplane was a Beech B100, serial number BE89. The logbooks were not provided for examination.
The maintenance chief, whose employment was terminated about one month after the accident, stated the airplane typically flew 200-400 hours per year, and the company had flown it about 800 hours since acquisition. He was unaware of any unresolved squawks; the owner usually had maintenance needs addressed immediately. The airplane had been out of service for almost 7 months the previous year due to propeller repair cost. The owner kept onboard Garmin GPS databases up to date. Overdue inspections included the 6-year landing gear inspection, 12-month items, and 3-year wing structure and wing bolt inspection.
Meteorological Information
The closest official weather observation station was Sandpoint, Idaho (KSZT), 46 nm west of the accident site at an elevation of 2,131 feet msl. A routine weather report issued at 2355 MST indicated wind from 220 degrees at 5 knots, visibility 10 miles, sky 2,800 feet overcast, temperature 0°C (32°F), dew point -3°C (27°F), altimeter 29.72 inches of mercury. Moon illumination was 35 percent.
Wreckage and Impact Information
The center of the debris field was about 2.5 miles north of the airport at an elevation of 4,180 feet. The debris path was about 290 feet long along a magnetic bearing of 125 degrees. The first identified point of contact was a topped tree with branches on the ground and a piece of composite engine nacelle with a hole. About 50 feet further, a 4-foot-tall tree stump had shiny splinters; its lower portion was displaced 30 feet in the debris direction with the top folded back. Underneath the tree trunk were the nose gear and control surfaces, followed by wing pieces.
One engine and propeller with all four blades attached was about 50 feet from the stump on the right side of the debris path (later identified as right engine). Next on the left side were outboard half of one propeller blade and another blade further into the field. Midway, several trees had sheet metal wrapped around them. A portion of the instrument panel was embedded in a tree about 15 feet above ground, with wiring bundle hanging down.
A large piece contained left and right horizontal stabilizers, vertical stabilizer, and part of one wing with landing gear strut attached. The rudder separated but was nearby. Next was a 6x8-foot twisted metal piece containing the throttle quadrant. About 100 feet right and downhill from that was a 10-foot section of the aft cabin, connected by steel cables to a 4x7-foot twisted metal piece. The furthest large piece was the left engine; its propeller hub with two blades had separated, and the other two blades were earlier in the debris field.
Medical and Pathological Information
The Forensic Science Division of the Montana Department of Justice completed an autopsy, determining the cause of death as blunt force injuries.
The FAA Forensic Toxicology Research Team performed toxicological testing of pilot specimens. Results indicated no carbon monoxide detected in blood (cavity), no test performed for cyanide, no ethanol detected in muscle or kidney, and no findings for tested drugs.
Tests and Research
Investigators from the NTSB, FAA, Textron Aviation, and Honeywell examined the wreckage at Avtech, Kent, Washington, on February 13, 2013. No mechanical anomalies were observed that would have precluded normal operation of the airframe or engines.
The engines had been modified from Honeywell models to National Flight Services, Inc., models per supplemental type certificates. The left engine (TPE331-6-511B, serial P-27185C) had a fractured starter/generator input shaft with an angular and twisted fracture surface. No metallic debris adhered to the chip detector. The engine inlet fractured and separated; earthen debris was on the first stage compressor impeller, and vanes were bent opposite rotation. The compressor case and plenum showed crush damage. Earthen debris was in the engine exhaust, and fine dried mud was on the forward suction side of third stage turbine blades. Metal spray deposits were on third stage turbine stator vanes. All four left propeller blades had leading edge damage; one blade section was not recovered but its tip was.
The right engine (TPE331-6-511B, serial P27190C) showed rotational scoring on the propeller shaft. The first stage compressor impeller had tearing and battering damage, with some vanes bent opposite rotation. Wood debris was in the engine inlet area. Metal spray deposits were on the suction side of third stage turbine stator vanes. All four right propeller blades had leading edge damage and chordwise scoring; one tip fractured and separated and was not recovered. All blades bent aft at midspan, exhibiting s-bending and tip curling.