History of Flight
On November 23, 2014, at about 0945 central standard time, an Aero Commander 500A airplane, registration N14AV, impacted terrain near McDade, Texas. The airline transport rated pilot, the sole occupant, was fatally injured. The airplane sustained substantial damage. It was registered to and operated by Aerial Viewpoint Aerial Photography under 14 Code of Federal Regulations Part 91 as a positioning flight. Visual meteorological conditions prevailed, and the flight operated without a flight plan. The flight departed David Wayne Hooks Memorial Airport (KDWH), Houston, Texas, at 0854 and was en route to Austin Executive Airport (KEDC), Austin, Texas.
The pilot was in radio contact with air traffic control and receiving flight following. He radioed his intention to descend for landing at KEDC. No distress calls were reported.
A local landowner heard the impact and called 911.
Personnel Information
The 63-year-old pilot held an airline transport pilot certificate with airplane multiengine land and instrument airplane ratings, a commercial pilot certificate with single engine land rating, a flight instructor certificate for single-engine, multiengine, and instrument airplane, and a mechanic certificate with airframe and power plant ratings. On May 8, 2014, he was issued a second-class medical certificate with the restriction "must wear corrective lenses." He reported 7,075 total flight hours, with 110 hours in the preceding 6 months.
Aircraft Information
The airplane, serial number 500A-914-22, was a high-wing, two-engine aircraft manufactured in 1960. It was powered by two 300-horsepower Continental Motors IO-520-E8B engines, each driving a metal, three-bladed, variable-pitch Hartzell EHC-G3YF-2YF full-feathering propeller. The last annual inspection occurred on October 1, 2014, at which time the airframe had accumulated 12,859.2 hours. The operator acquired the airplane in 1998, and it was configured for aerial surveying and photography.
Meteorological Information
At 0955, an automated weather reporting facility at Giddings-Lee County Airport (KGYB), about 16 nautical miles southeast of the accident site, reported wind from 240 degrees at 9 knots gusting to 14 knots, visibility 10 miles, clear sky, temperature 64°F, dew point 55°F, and barometric pressure 29.70 inches of mercury.
Communications
The pilot communicated with Austin approach control. At 0922:16, he reported at 6,500 feet; the controller issued the Austin altimeter of 29.66 inches. At 0927:59, the pilot reported descending, which was the last recorded transmission. The controller did not acknowledge this transmission. The last radar return at 0944:23 showed the airplane at 800 ft msl. At 0946:40, the controller terminated radar service and approved a frequency change. No distress calls were recorded.
A review of interactions found that one controller handled the airplane until the pilot reported descending out of 6,500 ft. The controller thought he acknowledged the transmission and watched the descent without noting anything unusual. He was then relieved. The relieving controller was briefed on active traffic, including N14AV. When he saw the data block had not moved, he terminated radar services, believing the pilot had switched frequencies. Later, the supervisor asked if any aircraft had been lost in the east sector.
Paragraph 10-2-5 of FAA Order 7110.65 states that when an unexpected loss of radar and communications occurs, controllers shall consider an emergency and notify the Rescue Coordination Center or Air Route Traffic Control Center.
Wreckage and Impact Information
The wreckage was in an open pasture with rolling terrain, about 65 yards east of a fence line. Impact signatures were consistent with a slow-speed, near-vertical impact. All four corners of the airplane and flight control surfaces were accounted for.
The initial impact point was a circular crater. About 6 feet on either side were both propeller assemblies. The left propeller was almost completely buried; the right was partially buried. Right propeller blades appeared fully feathered. Left blades were curled with polished leading edges, chordwise scratches and gouges.
Remaining wreckage, including fuselage, empennage, both wings, and left engine, was about 15 feet northwest. The right engine had separated and was about 25 feet northwest of the right wing. The fuselage was crushed and wrinkled along its entire length. The cockpit was distorted and crushed rearward. The left wing's leading edge had accordion crushing; the right wing had crushing on the inboard one-third. Both flaps appeared partially extended. Both main landing gear were fully retracted.
Flight control continuity was established from cockpit controls to ailerons, elevators, and rudder. The throttle quadrant was impact damaged: left throttle near full forward, right throttle fully aft. Both propeller controls were in the feather range and bent left. Both mixture controls were in full rich but fractured. The altimeter Kollsman window indicated between 29.72 and 29.73. The flap gauge showed ½ flaps. The battery switch was found off (set by first responders). Left generator switch on, right generator switch off. Left engine fuel cutoff open, aux pump off, ignition on both. Right engine fuel cutoff closed, aux pump off, ignition off. Landing gear handle up. Autopilot displayed roll, heading, and pitch on, altitude hold off. Emergency locator transmitter was armed and activated.
A Garmin GPSMap 296 was found and shipped to the NTSB laboratory for data download.
Both engines were partially examined on-site. The right engine's crankcase had a hole above the #2 cylinder. Its oil gauge housing extension was found disconnected. Both engines were sent for further examination.
Additional Information
Garmin GPSMap 296 Data
The GPS data contained the accident flight, though the date field recorded April 9, 1995, but time and route were consistent. The airplane departed KDWH about 0854, turned west, and cruised about 6,700 ft msl at about 138 knots groundspeed. At 0927, it began descending with decreasing groundspeed. The average descent rate was 440 ft/min. The last recorded point at 0944:35 was about 200 ft southwest of the impact point, at GPS altitude 610 ft msl, groundspeed 66 knots, descent rate 290 ft/min. Terrain elevation was about 520 ft msl.
Speeds and Engine Failure Procedures
According to the operator's manual, the minimum control speed with sudden failure of one engine and takeoff power on the other is 61 knots. Stall speed at maximum gross weight with zero bank is 63 knots flaps up and 57 knots flaps down.
Published procedure for engine failure during cruise: determine inoperative engine, feather, maintain 70% power on operative engine. Feather procedure: throttle closed, mixture idle cutoff, fuel valves closed, ignition off, propeller control to feather.
Assessment of Pilot's Abilities
A company employee and flight instructor observed the pilot from October 20 to November 7, 2014. He noted the pilot used the autopilot for every ferry leg, flew between 6,000–9,000 ft msl, was comfortable with the airplane, and maintained good control in instrument conditions. On one flight, the right engine's oil temperature was abnormal, so the flight returned to KDWH for repair. The pilot routinely preflighted and inspected oil and fuel quantities.
A notebook found in the wreckage contained no notes about an oil malfunction between October 20 and November 7. There were no maintenance log entries concerning corrective maintenance of either engine's oil system during that period.
Medical and Pathological Information
An autopsy by the Deputy Medical Examiner of Lee County, Texas, determined the cause of death as blunt force injuries and the manner as accident.
Forensic toxicology by the FAA Civil Aerospace Medical Institute found negative for carbon monoxide and ethanol. Detected drugs included acetaminophen, azacyclonol, cetirizine, diphenhydramine, fexofenadine, and naproxen. Cetirizine and diphenhydramine are antihistamines that cause drowsiness and may impair ability for hazardous tasks. The FAA recommends waiting at least 48 hours after cetirizine and 60 hours after diphenhydramine before performing safety-related duties.
Review of the pilot's medical history showed a history of allergies, cataracts, and primary angiitis of the central nervous system treated from 2002 to 2009, but he had been off medication for five years with normal neurologic exam.
Tests and Research
Engine Examinations
Both engines were examined under NTSB auspices. The left engine could not be test-run due to impact damage. Tear-down revealed no anomalies that would have precluded normal operation. The oil gauge housing extension was secured.
The right engine also could not be test-run. The left magneto and ignition harness were impact damaged. The oil sump contained metallic material consistent with connecting rods, bearings, and crankcase material. The oil pickup screen had a small amount of metallic material; the oil pump gears contained metallic material with scoring. The oil screen had significant metallic material. The oil gauge housing extension was found separated at the accident site, with no impact damage to the housing extension. The hose and clamps were not positioned to center the hose over the connection joint; the top clamp was below the extension bead. The hose material was not manufacturer-specified. Bearing signatures showed lubrication distress with scoring and thermal smearing. Connecting rods 1 and 2 had separated from their journals. All connecting rods and rod bearings displayed thermal discoloration consistent with lubrication distress.
Engine log books contained no recent entries regarding the oil gauge housing extension. Several entries documented oil changes and checks for leaks. The last entry on November 18, 2014, reported replacing oil with Aero Shell 100W, cleaning excess oil, checking for oil leaks (none found), and returning to service. That entry was endorsed by the pilot, who was also a mechanic.