History of Flight
On July 2, 2010, at 1219 central daylight time, a North American AT-6G, registration N92778, operated by a commercial pilot, was substantially damaged when it impacted the Gulf of Mexico about 1 mile south of Destin, Florida. The certificated commercial pilot and passenger were killed. Visual meteorological conditions prevailed and no flight plan was filed for the local flight that departed Destin-Fort Walton Beach Airport (DTS) at 1211. The personal flight was conducted under 14 Code of Federal Regulations Part 91.
The airplane was owned by the pilot. According to friends, his family was visiting for a wedding, and the pilot was giving family members rides. The accident flight was the pilot's second flight of the day; the passenger was his brother-in-law.
Several witnesses on the beach reported that the airplane had been performing aerobatic maneuvers along the beach. Just prior to the accident, the airplane was flying east along the beach, then turned west with its "smoke on." It began a steep climb, possibly a loop or a wingover. At the top of the climb, the smoke ceased and the airplane entered a spin. It descended in a spin until impacting the water.
Some witnesses thought the accident airplane may have been avoiding a banner-tow airplane, but FAA radar data and an interview with the banner-tow pilot indicated the banner-tow aircraft was about 500 feet mean sea level (msl) and 1/2 mile closer to shore when the accident airplane descended in a spin from about 1,200 feet msl. The banner-tow pilot stated he was flying east along the Destin shore, saw the accident airplane coming toward him about 100 feet above his altitude, then the accident airplane performed a steep left climbing turn south to maneuver further out over the water. The banner-tow pilot did not see the accident sequence and did not believe the accident pilot saw him.
Two witnesses on the beach, who were also T6 pilots and friends of the accident pilot, stated they were surprised he was performing maneuvers over the water at low altitude. They noted that the water did not provide any ground reference for altitude, position, or horizon, and they would have expected the airplane to be higher, about 3,000 feet msl, as that make and model needed significant altitude to recover from a stall or spin. Both witnesses further stated that the airplane was doing a series of lazy-eights (or wingover turns) when it became too slow, stalled, and completed a one-half turn spin. The airplane recovered from the spin and was in the process of recovering from the ensuing dive when it impacted the water.
Review of FAA radar data showed a target with a discrete transponder code on an easterly ground track at 12:14:23 at an altitude of 1,350 msl. The target descended to 150 feet at 12:17:11, climbed to 1,150 feet at 12:17:34, reversed track to west at 12:17:59 while descending through 650 feet, descended to 350 feet at 12:18:11, climbed to 1,350 feet at 12:18:23, then recorded altitudes of 950 feet and 850 feet at 12:18:35 and 12:18:47, respectively.
Personnel Information
The pilot, age 57, held a commercial pilot certificate with ratings for airplane single-engine land, airplane multiengine land, and instrument airplane. His most recent FAA third-class medical certificate was issued on November 3, 2009. Review of his most recent logbook revealed 1,923.9 total hours of flight experience. He had flown about 104 hours in the 90-day period and 19 hours in the 30-day period preceding the accident. He had accrued 14.2 hours in the accident airplane during the 90-day period and none in the 30-day period. A friend estimated he had accrued approximately 300 to 500 hours of experience in "T6s."
Aircraft Information
The two-seat tandem, low-wing, retractable-gear tailwheel airplane, serial number 182-486, was manufactured in 1943 and remanufactured in 1951. Its most recent FAA standard airworthiness certificate was issued on April 12, 1979. It was equipped with a Pratt and Whitney R1340, 550-horsepower radial engine and a Hamilton Standard two-blade constant-speed propeller. The most recent annual inspection was completed on March 26, 2010, at which time the airplane had accumulated 6,790.1 total hours of operation and the engine had accumulated 232.1 hours since overhaul. The airplane had been operated for 30.2 hours since that inspection.
Meteorological Information
The recorded weather at DTS, about 5 miles northwest of the accident site, at 1153 was: wind from 070 degrees at 6 knots; visibility 10 miles; few clouds at 2,800 feet; temperature 29 degrees Celsius, dew point 23 degrees Celsius; altimeter 30.06 inches of mercury.
Wreckage and Impact Information
The wreckage was located the same day about 3/4 mile south of the beach at a depth of 65 feet. Underwater video confirmed all major components were present at the site; however, during recovery, the fuselage separated from the center wing section. The engine, cockpit, and fuselage were recovered and examined on July 4, 2010. The engine remained attached to the fuselage and the cockpit area was crushed. Elevator, elevator trim, and rudder control cable continuity was confirmed from the cockpit area to broomstraw cable separations at the aft portion of the fuselage. The aileron control tubes had separated about the mid-cockpit area at the "Y bar." The throttle and mixture controls were found mid-range, and the propeller control was full-forward. The fuel selector was positioned to the left main fuel tank.
The propeller remained attached to the engine. One blade exhibited aft curling and chordwise scratches; the other exhibited s-bending, leading edge gouges, and chordwise scratches. Top spark plugs were removed from cylinders except the No. 3 top spark plug, which was missing. The spark plugs were light gray with some oil coating and their electrodes were intact. The propeller was rotated through 360 degrees. Compression was noted on cylinders, with water emanating from them. Continuity was confirmed through the engine to the magneto drive shafts, and both magnetos remained attached.
Portions of the wings and empennage were recovered on July 5, 2010, and examined again on July 21, 2010. The right wing exhibited accordion-type crushing on the leading edge, separated from the center wing section, and its skin was torn from rivets. A section of the left wing was crushed and separated from the center wing section, and a section of the left flap remained attached. The right flap and both ailerons were not recovered. Left and right wing fuel bladder tanks were breached. Both main gear remained attached to the center wing section and were in the retracted position. The center wing section was buckled and exhibited overstress damage.
The empennage had separated from the fuselage. The horizontal and vertical stabilizers remained attached. The right elevator remained attached to the horizontal stabilizer and was buckled in various locations. The rudder and left elevator had separated from their respective stabilizers and exhibited overstress damage.
Medical and Pathological Information
An autopsy on the pilot was performed by the State of Florida District One Medical Examiner's Office on July 6, 2010, noting the cause of death as "multiple blunt force injuries."
Toxicological testing by the FAA Bioaeronautical Science Research Laboratory revealed the presence of ethanol, methanol, and n-propanol; however, putrefaction was noted as "yes" and the report stated, "The ethanol found in this case may be the result of postmortem ethanol production and not from ingestion."
Review of the autopsy report and FAA medical records revealed a history of heart disease, but the pilot had a "good check-up" about 8 months prior. His wife, a nurse, stated he had been "great" since the check-up, ran on a treadmill three times per week for 30 minutes, performed aerobatics regularly with friends, and there was never concern about G-loading with his heart condition. At the time of the accident, she believed he was performing a lazy-eight, which was common for him.
Tests and Research
A Garmin GPSMAP 496 was recovered and sent to the NTSB Vehicle Recorders Laboratory. Data showed the accident airplane completed a short flight uneventfully just prior to the accident flight. The accident flight was also uneventful until 1218, when the airplane descended to 355 feet GPS altitude, reversed course to west, and increased groundspeed to 184 knots. It then climbed to about 1,200 feet and completed three lazy-eight turns. During the third turn, at 1,254 feet GPS altitude, groundspeed slowed to 66 knots. The airplane then descended to 467 feet GPS altitude 3 seconds later, and to 344 feet GPS altitude another 3 seconds later, which was the last target recorded.