History of Flight
On May 25, 2009, at 0846 eastern daylight time, an Aero Commander 500S, registration N73U, operated by Commonwealth Aviation Corporation, was substantially damaged after a loss of engine power and subsequent collision with terrain during a forced landing following takeoff from Daytona Beach International Airport (DAB), Daytona Beach, Florida. The certificated private pilot was seriously injured, and the pilot-rated passenger was killed. Visual meteorological conditions prevailed, and no flight plan was filed for the personal flight that departed about 0843 under 14 Code of Federal Regulations Part 91.
The airplane was cleared for takeoff from runway 7R. About one minute after takeoff, the pilot reported an engine failure and announced his intention to return for landing on runway 25R. Witnesses near the airport, approximately half a mile beyond the departure end of the runway, reported engine noise was surging as the airplane passed overhead, and one witness described a radical turn back to the airport. Two witnesses at a motorcycle repair shop stated that only one engine was running, and it was revving then conking out before revving again. As the engine surged, the airplane would shuffle left and right. One witness described the airplane just hanging there as it turned back. The airplane flew west out of view before crashing on the 1,000-foot grass safety area prior to the approach end of runway 25R.
Radar data showed that the pilot declared the emergency when the airplane was leveling off at about 1,000 feet, about 1.75 miles from the departure end of the runway. During the turn back, the airplane descended to 700 feet, then climbed back to 1,100 feet. During descent to the airport, data showed the airplane at 93 knots, 700 feet and 1 mile from the runway, and 90 knots, at 500 feet and half a mile from the runway.
In a written statement, the pilot described performing a full preflight inspection, with the fuel gauge reading 110 gallons. He performed a normal takeoff. The pilot stated: "We lost both engines shortly after takeoff, the engines surged from full throttle to idle." He maneuvered onto a left base traffic pattern leg to land in the opposite direction, feeling he had the field made. As the airplane descended, he prepared for a normal landing, dropping the gear and giving full flaps when he felt the runway was made. He had no recollection of the airplane stalling or the impact.
Personnel Information
The pilot held a private pilot certificate with ratings for airplane single-engine land, single-engine sea, multiengine land, and instrument airplane. His most recent FAA third-class medical certificate was issued July 17, 2007. He reported 1,250 total hours of flight experience at that time. Review of his logbook revealed approximately 1,470 total hours, of which 570 were in the same make and model as the accident airplane.
Aircraft Information
The airplane was manufactured in 1973 and had accrued 3,363 total aircraft hours. The most recent annual inspection was completed December 10, 2008, at 3,360 total aircraft hours. Originally delivered with Lycoming IO-540 six-cylinder engines, on November 18, 1978, Lycoming IO-720 eight-cylinder engines with twin turbochargers were installed.
On April 1, 2009, a maintenance receipt from an airframe and powerplant mechanic hired to diagnose a fuel quantity indication problem stated: "Fuel gauge off… installed replacement gauge…still reads off" and recommended further troubleshooting. The hobbs meter time reflected 2,208.7 hours. In an interview, the mechanic stated that the troubleshooting was performed at the pilot's home airport (DAB), not at his maintenance facility. He explained to the pilot that further troubleshooting would require defueling the airplane, and that he possessed the means to do so even with full tanks. The pilot stated he would prefer to wait until the quantity was reduced through use of the airplane.
Meteorological Information
At 0853, the weather reported at DAB included few clouds at 14,000 feet, scattered clouds at 25,000 feet, winds from 220 degrees at 4 knots, visibility 10 miles, temperature 24°C, dew point 20°C.
Wreckage and Impact Information
The airplane was examined at the site on May 25, 2009. No odor of fuel was present. All major components were accounted for. The airplane came to rest on flat, grassy terrain on airport property, 267 feet prior to the approach end of runway 7R. The wreckage path was oriented 240 degrees magnetic and was 140 feet in length. The airplane came to rest oriented 360 degrees.
Initial ground scars were consistent with the right wing, right engine nacelle, right main landing gear, nose enclosure, and left main landing gear. One propeller blade was partially buried in the scar consistent with the right engine nacelle. The right main landing gear and right aileron were separated and scattered along the wreckage path.
The wings remained attached, but the wing box structure was collapsed into the cabin area. The cabin was cut at the windshield and first cabin posts by rescue personnel. The leading edge of the right wing was crushed aft, and the wing was wrinkled along its entire span upwards toward the tip. The nose was crushed upwards and aft into the cockpit area. The instrument panel was fractured. The throttle, mixture, and idle cutoff levers for each engine were full forward. The empennage was fractured aft of the wing box structure but was intact aft of that point. The vertical fin, rudder, and elevators were intact and moved freely.
The engines were intact in their nacelles. The right engine showed minor impact damage to No. 1 and No. 3 intake tubes. The No. 1 cylinder bottom spark plug was broken by impact. The alternator was separated from its mounts. Two of three propeller blades showed twisting and aft bending with chordwise scratching at the tips; one blade was separated and located at the initial impact point.
The wreckage was moved to the parking ramp for further examination on May 26, 2009. Examination of the cockpit revealed that the left and right fuel valve switches and left and right fuel boost switches were in the "on" position. Both magneto switches were in the "both" position. Floor panels were opened, and flight control cable continuity was confirmed from the cockpit to all flight control surfaces. The landing gear were down and locked, and the flaps were deployed.
The left engine crankshaft was rotated by hand, establishing continuity through the powertrain and valvetrain to the accessory section. Compression was confirmed via the thumb method. The single-drive, dual magneto produced spark at all 16 terminal leads. The main fuel inlet line to the engine driven fuel pump was disconnected, and three drops of fuel were collected; the fuel and line were absent of water and debris. Spark plugs were removed; all 16 electrodes were intact, with 12 light tan and gray in color and 4 oil-fouled due to the wreckage position.
The right engine crankshaft was rotated, and continuity was established. Compression was confirmed. Both turbocharger impellers spun freely. The magneto produced spark at all 16 leads. The main fuel inlet line was disconnected, and no fuel was collected; the pump and line were absent of water and debris. Spark plugs were removed; all 16 electrodes were intact, but the top spark plug electrodes were massive type and the bottom plugs were fine-wire type. Fifteen electrodes were light tan and gray, and one was oil-fouled.
The fuel system had a capacity of 226 gallons, serviced through a single port on top of the left wing, with tanks interconnected to a center fuel sump that fed both engines. Fuel cells were opened through access panels; each was intact and contained only trace amounts of fuel. The airplane was leveled, and the drain petcock at the center fuel cell sump yielded 1 quart of fuel, which contained trace amounts of sediment and water.
Additional Information
On December 12, 2008, the pilot retrieved the airplane from the maintenance facility at Ormond Beach Municipal Airport (OMN) after the annual inspection. He departed with an unknown quantity of fuel and flew to DAB. Maintenance records showed the airplane had accrued 4.3 hours on the hobbs meter from the annual inspection to the accident date. The hobbs meter was operated by weight-on-wheels switch. Interpolation of the pilot's logbook indicated he had logged 6.5 hours and as many as 21 takeoffs in the accident airplane over that period. Entries in the logbook's remarks section showed fuel purchases: he noted "topped off tanks" or "bought gas." He bought gas on December 12, 2008 (64 gallons) and January 31, 2009 (74 gallons), confirmed by fuel receipts from DAB.
According to the Lycoming Operator's Manual, fuel consumption rate per engine at normal rated power was 33.9 gallons per hour; at 75 percent performance cruise, 23.3 gallons per hour. These rates did not account for engine start, taxi, takeoff, and climb.