History of Flight
On July 13, 2010, at 1700 eastern daylight time, a Beech 58 twin-engine airplane, registration N3081N, sustained substantial damage when it impacted terrain shortly after takeoff from Mackinac County Airport (83D), St. Ignace, Michigan. The private pilot and three passengers were fatally injured, and one passenger was seriously injured. The airplane was registered to Tri United, Inc., Skokie, Illinois, and operated by the pilot. Visual meteorological conditions prevailed, and an instrument flight rules (IFR) plan was filed for the personal flight under 14 Code of Federal Regulations Part 91.
The flight originated from Chicago Executive Airport (PWK), Wheeling, Illinois, at 1210 and arrived at 83D at 1354. According to a fixed based operator (FBO) representative at 83D, the pilot asked if he was at Mackinac Island; the representative pointed out the island through a window. The airplane then departed 83D and arrived at Mackinac Island Airport (MCD) a few minutes later.
At approximately 1630, the airplane returned to 83D from MCD and obtained 60 gallons of fuel. At 1644, the pilot contacted air traffic control to amend his IFR clearance.
Witnesses, mechanics at a local maintenance facility, observed the airplane attempt takeoff on runway 25 three times. During the first attempt, the airplane traveled about halfway down the runway and aborted the takeoff. The pilot taxied back and attempted a second takeoff without an engine run-up; this time the airplane traveled about three-quarters of the runway and aborted again. One witness reported that during the second takeoff roll, the engines did not sound at full power and the pilot appeared to have difficulty maintaining directional control.
For the third takeoff attempt, again without an engine run-up, a mechanic witness stated, "It appeared and sounded as if the right engine was running properly and the left engine was not at the same RPM. The pilot was having difficulty maintaining directional control...with the left engine sputtering and misfiring and traces of black smoke coming from the left engine exhaust." Witnesses observed the airplane become airborne near the departure end of the runway with wings rocking, and the left wing impacted the northbound lanes of Interstate 75, about 1,000 feet from the departure end. The airplane continued through the median, crossed the southbound lanes, and came to rest inverted in a grassy area. A post-crash fire consumed most of the airplane.
The seriously injured passenger, seated in the rear, exited after the accident. He reported sleeping at the time and had no recollection of the sequence.
Personnel Information
The pilot, aged 73, held a private pilot certificate with single-engine, multi-engine land, and instrument ratings. His most recent FAA third-class medical was on December 30, 2008, and he received a Special Issuance Medical Certificate valid until December 31, 2010, with a corrective lenses restriction.
The pilot's flight logbook was destroyed. On his last medical application, he reported 2,211 total flight hours with 67 in the previous six months.
FAA records show the pilot obtained his single-engine land rating on May 22, 1989; instrument rating on May 27, 1990; and multi-engine land rating on August 29, 1991.
On December 7, 2006, the pilot was reexamined by the FAA in the accident airplane due to an undisclosed violation, and the reexamination was disapproved. On January 9, 2007, another reexamination in the same airplane was also disapproved, and the pilot voluntarily surrendered his multi-engine land and instrument ratings.
On July 9, 2009, he received his multi-engine land rating again, reporting 2,985 total hours and 2,097 hours in the accident airplane make and model. He received a single-engine instrument rating on December 7, 2009, reporting 3,147 total hours, and a multi-engine instrument rating on December 29, 2009, reporting 3,166 total hours and 2,238 hours in the accident airplane make and model.
Aircraft Information
The airplane was a 1987 Beech 58 (Baron), serial number TH-1526, a six-place twin-engine with retractable tricycle landing gear. It was powered by two 300-horsepower Teledyne Continental Motors IO-550-C engines (left serial 271844-R, right 271853-R), with 3-blade McCauley propellers.
The most recent annual inspection was on November 18, 2009, at 3,902.6 airframe hours. The engines' last 100-hour inspection was the same date, at 378.9 hours since major overhaul.
Weight and balance documentation was not located, but based on occupant weights, estimated fuel, and baggage, the airplane was within gross weight limits at the time of the accident.
Meteorological Information
Weather reported at the time: clear sky, calm winds, temperature about 80°F. Density altitude was calculated at approximately 2,300 feet.
Airport Information
Mackinac County Airport (83D) is a public, non-towered airport 2 miles northwest of St. Ignace, Michigan, at elevation 624 feet. It has one runway, 7/25, concrete surface, 3,800 feet long by 75 feet wide.
Fuel records from the FBO showed the accident airplane received 60.33 gallons of fuel. Fuel tests from the FBO revealed no anomalies.
Wreckage and Impact Information
Initial ground impact was on the northbound lanes of Interstate 75, about 1,000 feet west of runway 25, on a debris path oriented approximately 230° magnetic. The main wreckage (fuselage, empennage, both wings, right engine) came to rest inverted about 150 feet from initial impact. Grass scorched by the postimpact fire extended north and around the main wreckage.
The fuselage was consumed by fire; cockpit and instrument panel destroyed. Seat frames separated from attachments. Nose landing gear remained attached in the retracted position. Empennage partially consumed; flight control surfaces remained attached.
Right wing partially consumed; aileron and flap consumed. Flap actuator consumed, position unknown. Landing gear retracted. Engine attached to firewall, fire damaged. Propeller blades showed leading edge gouging, S-type bending, and chordwise scratching.
Left wing bent aft, twisted upright, consumed by fire. Aileron separated and partially consumed; flap consumed. Landing gear retracted. Left engine separated and came to rest in debris path. Propeller blades similar damage.
Flight control continuity was confirmed to all surfaces. No preimpact anomalies were observed.
Pathological Information
An autopsy was not performed. FAA's CAMI toxicology on pilot's blood: negative for carbon monoxide, cyanide, and ethanol. Detected: unspecified level of Amlodipine (calcium channel blocker for blood pressure), unspecified level of Atenolol (beta blocker for blood pressure/heart rate), and 5.6% Hemoglobin A1C. Atenolol use was not reported on his most recent medical application.
Medical records showed the pilot had recurrent coronary artery disease with angioplasties in 1999, 2000, 2003, and 2008. Cardiovascular testing in January 2010 was normal. He was diagnosed with obstructive sleep apnea but did not report it to the FAA; he stopped using CPAP. He was a type-2 diabetic controlled with oral medication.
No relevant speech patterns indicating a medical issue were found in air traffic control communications.
Tests and Research
Engines were examined at Teledyne Continental Motors. Due to impact and fire damage, they could not be test run; teardown inspections showed no anomalies preventing normal operation. The left engine throttle and fuel control unit bench tested normally. The left engine fuel pump was damaged but disassembly showed no anomalies; fuel manifold valve normal. The right engine throttle and fuel control unit was damaged and could not be bench tested; fuel pump damaged but disassembly normal; fuel manifold valve fire-damaged but disassembly normal.
Propellers were examined at McCauley; blade angles at impact were in the low pitch operating range. No anomalies noted.