History of Flight
On January 19, 2013, about 1700 central standard time, a Beechcraft Baron 95-B55, registration N143E, impacted terrain near Mangum, Oklahoma. The commercial-rated pilot and two passengers were fatally injured, and the airplane sustained substantial damage. The airplane was registered to and operated by JS Leasing, LLC, under 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed. The local flight originated from Scott Field Airport (2K4), Mangum, Oklahoma.
According to persons familiar with the flight, the airplane had its annual maintenance inspection completed prior to the flight. The pilot started the airplane, performed a taxi test down the runway, then stopped and picked up the two passengers before departing.
Witnesses reported hearing the sound of an airplane and observed it. They noted that it sounded like the airplane "sputtered," before it nosed dived into a spin, which appeared to flatten out before the airplane collided with the ground.
Personnel Information
The pilot held a commercial pilot certificate with ratings for airplane single-engine and multiengine land, and instrument-airplane. A third-class Federal Aviation Administration (FAA) medical certificate was issued on November 20, 2012, with the restriction "holder shall possess glasses for near/intermediate vision." A review of the pilot's logbook revealed a total flight time of 2,170.1 hours, with 919.3 hours in single-engine airplanes and 1,170.5 hours in multiengine airplanes. For calendar year 2011, he had 1.9 hours in single-engine and 16.0 hours in multiengine airplanes; for calendar year 2012, he had 7.2 hours in single-engine and 14.4 hours in multiengine airplanes, which was in the accident airplane. His last recorded flight in the accident airplane was on June 1, 2012, and his last logbook entry was on January 12, 2013, in a single-engine airplane. According to the logbook, the pilot's last flight review was on September 21, 2010, conducted in the accident airplane.
The right-seat passenger held a private pilot certificate with ratings for airplane single-engine land and flight engineer (turbojet). He also held a mechanic certificate with airframe and powerplant ratings. He was issued a third-class medical certificate on March 6, 2012, with the limitation "must wear corrective lenses for near and distant vision." At the date of application, he reported 54 total flight hours, with 5 hours in the last six months.
Aircraft Information
The Beechcraft Baron B55 is a twin-engine airplane powered by two Continental IO-470 reciprocating engines. It is typically configured for four to six seats, with retractable landing gear, flaps, and full-feathering propellers.
A review of the airplane's maintenance records revealed that the recent annual inspection, reported to have been completed on the day of the accident, had not been entered into the airplane's paper maintenance logbooks. The last recorded annual inspection was on August 5, 2011, with a Hobbs time of 5,193.9 hours. Additionally, the airplane's altimeter and static system were last tested on December 7, 2010.
Meteorological Information
At 1655, the automated weather observation facility at Altus Air Force Base, Altus, Oklahoma, about 30 miles southeast of the accident site, reported calm wind, visibility 10 miles, clear sky, temperature 61°F, dew point 35°F, and barometric pressure of 30.12 inches of mercury. At 1915, the automated weather observation facility at Altus/Quartz Mountain Regional Airport, about 25 miles southeast, reported calm wind, visibility 10 miles, clear sky, temperature 50°F, dew point 34°F, and barometric pressure of 30.18 inches of mercury.
Communications and Radar Information
Scott Field Airport (2K4) is a non-towered airport, and the pilot was not in communication with air traffic control; no distress calls were reported.
A review of radar information revealed a track consistent with the accident airplane departing from Mangum airport at about 1644. The track headed north-northwest toward Sayre Municipal Airport (3O4), about 18 miles away. The radar track disappeared as it neared 3O4, then reappeared heading south. About 5-6 miles from 2K4, the airplane performed a large 360-degree left turn before resuming southward heading. The track then turned east, then north away from 2K4. The radar indicated the airplane slowed as it turned north. The track ended near the accident site at 1701. Only one radar plot showed the airplane's altitude: 3,600 feet (approximately 2,000 feet above ground level); otherwise, altitude (Mode C) was not received.
Wreckage and Impact Information
The National Transportation Safety Board and an FAA inspector examined the wreckage on site. The airplane came to rest upright in open ranch land approximately five and a half miles northwest of 2K4. The airplane remained relatively intact; both propellers had separated and were about 3 feet in front of their respective engines. The surrounding area had no ground scars, consistent with the airplane impacting terrain with little forward velocity. According to the mechanic who performed the annual, the main fuel tanks were almost full, and the auxiliary tanks were full before departure. First responders reported fuel on site, and a post-impact fire erupted when they attempted to cut the battery cable. The fire was extinguished before consuming the wreckage.
The fuselage sat flat on the ground with heavy impact damage; the cabin top had been cut and removed by first responders. The fuselage back to the empennage had heavy bending and buckling. The instrument panel was pushed up and back slightly into the cockpit area.
The empennage exhibited damage to both sides of the horizontal stabilizer; the elevator remained attached to the stabilizer. The vertical stabilizer remained partially attached to the aft fuselage; the rudder was on the ground aft of the empennage, with the rudder and trim tab bent aft. Both wings showed buckling and crushing signatures; each aileron and flap remained attached. The flaps appeared in the retracted position, and the landing gear was extended. The landing gear handle on the panel was broken; however, the landing gear bellcrank was in the extended (down) position. The fuel selectors sustained impact damage and were pointing at the auxiliary fuel tanks. The Hobbs meter read 5,203.4 hours. The leading edge of the left wing received fire damage; both nacelle areas had slight thermal damage from the post-crash fire.
Both engines remained in their respective nacelles. Both propellers separated from their crankshaft flanges, with bolts stripped from the flanges.
Medical and Pathological Information
The Board of Medicolegal Investigations, Office of the Chief Medical Examiner, Oklahoma City, Oklahoma, conducted autopsies on the pilot and the pilot-rated passenger. The cause of death for both occupants was determined to be "multiple blunt force trauma." In addition to traumatic injuries, the pilot's autopsy identified thickening of the walls of the heart. The pilot had told the FAA he was being treated for high blood pressure on his last aviation medical exam and had been issued a third-class medical certificate with a limitation for wearing corrective lenses.
The FAA Bioaeronautical Sciences Research Laboratory performed toxicology tests on the pilot. Tests were negative for carbon monoxide and ethanol. The tests identified amitriptyline, nortriptyline, and nadolol in the liver and amitriptyline (0.069 µg/ml), nortriptyline, and nadolol in heart blood.
Amitriptyline is a tricyclic antidepressant also used for chronic pain; its therapeutic range is 0.005 to 0.200 µg/ml, and it carries an FDA warning: "may impair mental and/or physical ability required for the performance of potentially hazardous tasks (e.g., driving, operating heavy machinery)." Nortriptyline is the primary metabolite of amitriptyline. Nadolol is a beta-blocker used for hypertension.
Tests and Research
The wreckage was transported to a salvage facility, where both engines were examined by the NTSB, FAA, and a technical representative from the engine manufacturer. Both engines were missing their dataplates. Continuity was established from the front of the crankshaft to the rear gear drive section and through the valve train. Each cylinder was borescoped and produced suction and compression during a thumb test. The left magneto on the left engine had separated on impact; the other magnetos were removed and rotated, producing a spark at each terminal. Both fuel screens were not plugged but contained a small amount of unidentified contaminant. The engine fuel flow divider and engine-driven fuel pumps were examined with no abnormalities noted.
The engine inspection did not reveal any abnormalities that would have prevented normal operation.