History of Flight
On November 10, 2013, at approximately 1546 central standard time, a Mitsubishi MU-2B-25 twin-engine airplane, registration N856JT, impacted wooded terrain while maneuvering near Owasso, Oklahoma. The flight was operated by the commercial pilot, the sole occupant, under 14 CFR Part 91 as a personal flight. Visual meteorological conditions prevailed, and an instrument flight plan had been filed. The flight departed Salina Regional Airport (SLN), Salina, Kansas, at about 1503 and was en route to Tulsa International Airport (TUL), Tulsa, Oklahoma.
After takeoff, the airplane was radar identified and cleared to climb to 9,000 feet, later to 17,000 feet. The flight proceeded normally through air traffic control sectors. At 1534, the pilot contacted Tulsa approach and reported leaving 11,600 feet for 10,000 feet. The controller advised expected vectors for a visual approach to runway 18L. At 1542, the pilot reported the airport in sight and was cleared for a visual approach, then instructed to contact TUL tower. The tower controller cleared the pilot to land on runway 18L and requested a speed reduction to 150 knots.
After passing the outer marker, the airplane began a left turn. At 1544:48, the tower controller called the airplane, and the pilot replied, "I've got a control problem." At 1545:06, the pilot reported a left engine shutdown. The tower declared an emergency and attempted further contact but received no response. Radar data showed the airplane complete a 360-degree left turn near the outer marker at 1,100 feet msl, then radar contact was lost.
Seven witnesses observed the airplane in a shallow left turn at altitudes between 400 and 800 feet agl. Four witnesses recalled the landing gear extended; two observed one engine propeller not rotating or slowly rotating. Some witnesses reported unusual engine noise, others saw no smoke. The airplane was seen in a left turn, then wings rocking, followed by a right bank and a hard left bank, then spiraling toward the ground.
Personnel Information
The 51-year-old pilot held a commercial pilot certificate with single-engine, multiengine, and instrument ratings, as well as a flight instructor certificate. His most recent FAA third-class medical certificate was dated October 15, 2013, with no limitations. He had accumulated at least 2,874.4 total flight hours, including 1,534.9 hours in multiengine airplanes, primarily in a Cessna 421B. Interviews with associates described him as a very good aviator who meticulously followed checklists.
Piloting an MU-2B series airplane requires compliance with Special Federal Aviation Regulation (SFAR) No. 108. The pilot completed ground school November 4–10, 2013, at Professional Flight Training, L.C. (PFT) in Salina, Kansas, with about 32 hours of instruction. Flight training was conducted entirely in the accident airplane, totaling 11.5 Hobbs hours. On the morning of the accident, the pilot satisfactorily completed the phase check and received an SFAR endorsement. The accident flight was his first solo flight in the MU-2B-25.
During training, the pilot performed approach-to-stall maneuvers in various configurations and single-engine procedures, including an engine shutdown in flight and a single-engine landing. The instructor taught both the SFAR method of stall recovery (emphasizing minimizing altitude loss) and the FAA Advisory Circular method (reducing angle of attack).
Aircraft Information
The 1973 Mitsubishi MU-2B-25, serial number 306, was a twin-engine turboprop high-wing airplane. It was equipped with two Honeywell TPE331-10AV-511M engines and Hartzell three-blade propellers. The most recent inspection was a 100-hour/annual inspection completed on September 19, 2013, at 6,581.4 total airframe hours. Weight and balance computations indicated the airplane was within limits at landing.
The airplane was configured with a Garmin G600 avionics system, standard engine gauges, and an annunciator panel. It also had a Bendix M4D autopilot and a Negative Torque Sensor (NTS) system for automatic propeller feathering in case of engine failure. The stall warning system used a control wheel shaker.
Post-Accident Investigation
Examination of the wreckage revealed fire damage. A fire-damaged pilot checklist was found, but the single-page quick reference checklist was not located. A training checklist from PFT, which was not FAA-accepted, was found melted to the circuit breaker panel. The NTSB examined cockpits of 10 other MU-2Bs and found unaccepted checklists in three.
The pilot's handwritten training notes included reminders such as "120 knots, never go below" and "For engine out, center ball."
The pilot's cellular telephone records and interviews indicated no abnormal health issues or routines in the 72 hours before the accident.