N3670DBeech 95-B55 (T42A) · 1980

On September 10, 2022, about 1237 eastern daylight time, a Beech BE-55, N3670D, was substantially damaged when it was involved in an accident near Hartwell, Georgia. The private pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight.

According to family, the pilot flew from Florida to Georgia to attend an event. A review of ADS-B flight track data revealed that the airplane departed Punta Gorda Airport (PGD), Punta Gorda, Florida, about 0941. The airplane flew on a generally northwest heading at 10,500 ft mean sea level (msl), then descended to 9,500 ft msl as it continued toward Anderson Regional Airport (AND) for about 1 hour 50 minutes. ATC cleared the pilot for an RNAV approach to runway 5 and instructed him to switch to the non-towered airport common traffic advisory frequency.

At 1211, the pilot executed a missed approach and contacted ATC and requested another RNAV approach. The controller issued instructions to join the approach course and cleared the pilot for the approach; however, the pilot began to descend and maneuver, and was unable to join the final approach course. The controller asked if he needed assistance; the pilot responded negative and that he needed to “get reset.” The pilot was issued instructions to hold an altitude of 4,000 ft msl and to fly a heading of 090°, but he turned to a heading of 270° instead. The controller asked if he was having trouble with the autopilot or gyros; he responded, “I think the gyro might be an issue here.” The controller then offered the ILS approach to runway 5, and the pilot accepted. At 1230, the pilot advised the controller that he was on a 120° heading and the controller responded that he showed him on a 100° heading. The pilot acknowledged the transmission and then the controller confirmed that he was now established on a heading. The controller cleared the pilot for the approach and instructed him to turn right to heading 310°, but he did not intercept the localizer. The controller then instructed the pilot to stop his turn and maintain 3,000 ft msl. No further communications were received from the pilot.

According to ADS-B flight track data, at 1235 the airplane was at 3,975 ft msl; about 30 seconds later, the airplane began a right turn. The airplane completed two right turns and descended to 1,900 ft. The airplane briefly climbed to 2,750 ft msl and began a left turn. The last track data was observed at 1237, as the airplane descended through 1,825 ft msl, about 1,165 ft above ground level (agl). The airplane impacted Lake Hartwell about 9 nautical miles south of the AND airport. (See figure 1.)

Figure 1. ADS-B Flight Track Overlay

Figure 2. Final segment of the accident flight track with time, altitude, ground speed, and heading information.

The pilot’s logbook was not located.

The airframe and engine logbooks were not located.

Observations from Anderson Regional Airport (AND) in Anderson, South Carolina, which was at an elevation of about 780 ft and located 10 miles northeast of the accident location, reported ceilings between 800 ft and 1,000 ft agl surrounding the accident time. Light rain and mist were also observed.

A model sounding for near the accident site identified a saturated environment and clouds between about 1,500 ft and 5,200 ft. Clouds may have also existed outside these boundaries. Wind at 3,000 ft was from the east at about 15 knots.

The weather radar imagery from the accident time depicts what likely amounts to light precipitation at the accident location. Satellite imagery depicts clouds across the region, and infrared data identifies the cloud top heights at about 8,000 ft.

There was no record of the pilot accessing weather briefing services from Leidos Flight Services (LFS) and 3rd party vendors utilizing the LFS system on the day of the accident.

The airframe and engine logbooks were not located.

The airplane was recovered five days after the accident and transported to a facility for examination. The fuselage was intact and had upward crushing on the bottom of the fuselage; both wings and horizontal stabilizers were pushed upward. Flight control cable continuity was established from the control inputs to the bellcranks, and then to the control surfaces. The propellers remained attached to their respective engine crankshaft flange, and minor scratches were present along the blade tips. The right and left flap actuators were both in the retracted position, and the handle was in the UP position. The nose and main landing gear were all retracted.

The instrument panel was intact. The tachometer indicated 3,693.0 hrs. The left ignition switch was in the RIGHT position. The right ignition switch was in the LEFT position. The left fuel selector handle was in the LEFT position. The right fuel tank selector handle was out of position, pointed to the upper right. The throttle, mixtures, and propeller controls were mid-position. The heading aid was on 174°. A Garmin G5 and King KFC 200 autopilot was installed; the autopilot select push switch labeled HDG/GPS was in the HDG position.

The engines were partially separated from the airframe consistent with impact, and they were removed to facilitate recovery. The engines were manually rotated and internal geartrain continuity was confirmed, and thumb compression was obtained on all cylinders. The oil sump pans were crushed upward. The oil filters and their screens were removed and examined, they were free of debris and non-ferrous material. The fuel screens were removed, and were free of debris. The left and right magnetos remained attached to both engines; all produced spark on all leads. All spark plugs were removed and were light grey in color and in normal condition when compared to the Champion Check-A-Plug Chart.

The cylinders were examined with a lighted borescope and no anomalies were noted with the piston faces, cylinder walls, or valves. The left and right engine-driven vacuum pump drive shafts were intact and expelled air when rotated, and the carbon veins were intact.

A Garmin GTN 750 was recovered from the airplane and sent to the National Transportation Safety Board (NTSB) Vehicle Recorder laboratory. The SD card was removed and determined to be a supplemental data card that contained navigational information; no data was recovered from the Garmin GTN 750.

A J.P. Instruments EDM-790 was recovered from the airplane and sent to the NTSB Vehicle Recorder laboratory. The event flight was the last flight of the recording, and its duration was about 3 hours and 7 minutes. In addition to the engine parameters, the unit also recorded GPS altitude, position, and ground speed. The EDM showed an increase in GPS altitude, consistent with takeoff, about 09:40. The aircraft began descending about 12:00, to an altitude of about 2,500 ft during its initial approach, before climbing back to 3,000 ft. The aircraft descended again to about1,600 ft before climbing back to 4,000 ft. The aircraft’s final recorded descent began at 12:35:45. The recording ended at 12:37:05. No engine abnormalities were noted.

A KI 256 Flight Director Indicator (attitude indicator), KH 102A Directional Gyro, and KI 525A Pictorial Navigation Indicator HSI (horizontal situation indicator) were retained for further examination. The flight director was impact damaged, which precluded functional testing. The gyro capsule rotated smoothly; the fast erect vanes were dislodged from the capsule due to impact forces. The gyro capsule and rotor assemblies contained water and were corroded. The rotor and capsule bearings rotated smoothly. No rotational scoring was detected on the rotor and capsule assemblies. No preimpact anomalies were observed.

The directional gyro was impact damaged, which precluded functional testing. The gyro capsule rotated freely. The rotor assembly was removed from the rotor capsule and the rotor turned freely on the bearings. Water and corrosion was present in the gyro assembly. No rotational scoring was noted in the rotor and capsule assembly. A potentiometer was broken off the top circuit board, and impact witness marks were present.

The HSI was impact damaged, which precluded functional testing. The rear electrical connectors were damaged. The internal gearing was intact and there were no missing teeth. Water and corrosion were present in the assembly. The photodetector was tested and functioned normally.

Spatial Disorientation

The FAA Civil Aeromedical Institute's publication, "Introduction to Aviation Physiology," defines spatial disorientation as a “loss of proper bearings; state of mental confusion as to position, location, or movement relative to the position of the earth.” Factors contributing to spatial disorientation include changes in acceleration, flight in IFR conditions, frequent transfer between visual flight rules and IFR conditions, and unperceived changes in aircraft attitude.

The FAA’s Airplane Flying Handbook (FAA-H-8083-3B) describes some hazards associated with flying when the ground or horizon are obscured. The handbook states, in part, the following:

The vestibular sense (motion sensing by the inner ear) in particular can and will confuse the pilot. Because of inertia, the sensory areas of the inner ear cannot detect slight changes in airplane attitude, nor can they accurately sense attitude changes that occur at a uniform rate over a period of time. On the other hand, false sensations are often generated, leading the pilot to believe the attitude of the airplane has changed when, in fact, it has not. These false sensations result in the pilot experiencing spatial disorientation.

The Georgia Bureau of Investigation, Division of Forensic Sciences, performed the pilot’s autopsy. According to the pilot’s autopsy report, his cause of death was multiple blunt impact injuries and his manner of death was accident. No significant natural disease was identified.

Postmortem toxicological testing by the Federal Aviation Administration (FAA) Forensic Sciences Laboratory identified ethanol at 0.045 g/dL in the pilot’s cavity blood. Ethanol was not detected in the pilot’s urine. N-propanol was also detected at a low level in cavity blood and was not detected in urine.

Ethanol is the intoxicating alcohol in beer, wine, and liquor, and, if consumed, can impair judgment, psychomotor performance, cognition, and vigilance. FAA regulation imposes strict limits on flying after consuming ethanol, including a prohibition on piloting a civil aircraft while having a blood ethanol level of 0.04 g/dL or greater. Alcohol consumption is not the only possible source of ethanol in postmortem specimens. Ethanol can sometimes be produced by microbes in a person’s body after death.

N-propanol is another alcohol that can be produced by microbes in a person’s body after death. Detection of n-propanol in a postmortem specimen is potentially indicative of postmortem microbial activity in the specimen.