History of Flight
On June 24, 2008, at 1020 central daylight time, an Aero Commander 500S, registration N411JT, operated by Central Air Southwest, was destroyed when it impacted terrain after losing power on both engines while maneuvering near Linwood, Kansas. The training flight was conducted under 14 CFR Part 91 without a flight plan. The two commercial pilots on board—the company's chief pilot/director of operations and a pilot receiving a flight check—sustained fatal injuries. The local flight departed at 0927 from Charles B. Wheeler Downtown Airport in Kansas City, Missouri.
Witnesses reported hearing sputtering engines followed by silence before the airplane struck the ground nose-first. One witness estimated three to four seconds elapsed between the engine sputter and impact.
Personnel Information
The pilot-in-command, age 47, held commercial pilot and flight instructor certificates with single/multiengine and instrument ratings. He had 10,500 total flight hours, including 9,400 in multiengine airplanes and 7,550 in the Aero Commander. He was promoted to chief pilot in 1987 and became director of operations in 1988.
The pilot-in-training, age 24, held commercial pilot and flight instructor certificates with single/multiengine and instrument ratings. He had 1,200 total flight hours, including 224 in multiengine airplanes and 7 in the Aero Commander. He had been employed for approximately two weeks and was undergoing an FAA Part 135 standardization ride.
Aircraft Information
N411JT (serial number 3097) was a 1971 Aero Commander 500S powered by two Lycoming IO-540-E1A5 engines rated at 290 horsepower each, driving Hartzell HC-C3YR-2UF three-blade, all-metal, full-feathering, constant speed propellers. As of June 20, 2008, the airframe had 12,426.6 total hours. The left engine had 1,055.2 hours since overhaul; the right engine had 122.4 hours since overhaul.
Meteorological Information
Weather conditions recorded at Lawrence Municipal Airport near the accident time included wind from 080–100 degrees at 6–7 knots, visibility 9 statute miles, broken ceiling at 2,100 feet, temperature 25°C, dew point 20°C, and altimeter 30.08 inches of mercury. Remarks noted lightning distant north and a thunderstorm that began and ended near the time of the accident.
Flight Recorders
Downloaded GPS data indicated the airplane departed Kansas City, flew to Topeka where it made two approaches, then to Lawrence for a touch-and-go landing. The airplane then flew eastbound to a practice area in Leavenworth County, performing a 360-degree left turn followed by a right turn. Altitude and airspeed began decreasing steadily; between 1133:27 and 1136:58 GPS time, the airplane flew below 1,000 feet. Data recording stopped as the airplane entered a steep descent from 742 feet.
Wreckage and Impact Information
The impact point exhibited no lateral ground scar. The nose was 53 degrees down on a magnetic heading of 068 degrees. The fuselage was broken aft of the wings; the tail was aligned on 115 degrees. The landing gear was extended, flaps set to approach (one-quarter down), mixture and propeller controls full forward, throttles mid-range. One airspeed indicator was jammed between 85 and 90 mph. The overhead switch panel was found 15 feet forward; the left fuel shutoff valve was closed, the right destroyed. The left boost pump switch was on. Fuel valves in the fuel sump were open. Fuel tanks were breached with no fuel remaining; only residual fuel was found in engine supply lines.
Medical and Pathological Information
Autopsies revealed both pilots died of multiple blunt force injuries, ruled accidental. Toxicology detected no drugs or ethanol in the pilot-in-training; no drugs in the pilot-in-command. Ethanol (11 mg/dL) was detected in muscle tissue of the pilot-in-command.
Tests and Research
Both engines and propeller assemblies were disassembled and examined; no anomalies were found. Both propellers were in low-pitch/high-rpm setting. Boost pumps tested satisfactorily. Fuel shutoff valves operated normally under battery power. The principal operations inspector noted company routine: after steep turns, boost pumps were turned off and the airplane configured for landing to demonstrate minimum control airspeed maneuvers. Adjacent switches for boost pumps and fuel shutoff valves were identified as a potential source of confusion.
Probable Cause
No probable cause was stated in the source.