ERA24FA053

The pilot’s decision to descend below the minimum decision altitude of the instrument approach without having the appropriate runway visual references distinctively identified and with the visibility and ceiling below the minimum that was prescribed for the approach, which resulted in controlled flight into terrain.

The pilot was on an instrument flight rules (IFR) flight and had performed several instrument approaches to two different airports near the departure airport. After performing the practice approaches, the pilot returned to his home airport to perform a final instrument approach and landing. The pilot reported to air traffic control (ATC) that he would cancel his IFR clearance after he descended below the cloud layer surrounding the airport. The pilot never made any emergency declarations to ATC throughout the flight. ADS-B data revealed that the airplane descended toward the runway, and track data was lost about 4,350 ft short of the runway and right of the runway centerline. A video surveillance camera captured the fireball of the impact, as well as audio, which indicated that the engine was operating at a high rpm just before impact. The instrument approach the pilot attempted had a minimum decision altitude (MDA) between 384 and 424 ft above ground level (agl) at the airport; the exact MDA was dependent on the type of equipment the airplane had installed. The instrument approach also required 1 statute mile of visibility. The reported weather at the time of the accident had an overcast ceiling of 300 ft agl, which was below the MDA of the instrument approach. And while the latest reported visibility at the airport was 1.75 miles, the visibility from the surveillance camera was less than 1 mile. The camera visibility was below the minimum requirements for the instrument approach into the airport. Postaccident examination revealed the airplane was destroyed by post-impact fire. Further examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation; the condition of the airplane’s navigational equipment could not be determined due to the extensive fire damage. However, before the accident, the pilot had successfully performed four other area navigation (RNAV) approaches in the local area, indicating the navigational equipment was working correctly during the accident flight. The pilot’s toxicology results indicate he had used the sedating antihistamine medication diphenhydramine. The diphenhydramine level in postmortem iliac blood was low. While possible impairing effects related to diphenhydramine use cannot be entirely excluded, the toxicology results in this case provide no clear evidence that diphenhydramine effects contributed to the accident. The pilot’s elevated carboxyhemoglobin and the detection of cyanide in his blood can be attributed to effects of smoke inhalation during the post-crash fire, and do not constitute evidence of impairing pre-crash exposure.

According to FAA airman records, the pilot held a commercial pilot certificate with ratings for airplane single-engine land. The pilot also held an instrument airplane rating. According to the pilot’s training record for his instrument rating, the pilot had accumulated 81.2 simulated instrument hours, and 3.4 actual instrument hours. The last entry in the training record was on April 18, 2021. The pilot’s personal flight logbooks and any further training records were not located. According to the pilot’s last FAA medical examination, dated May 3, 2023, the pilot reported having a total flight time of 628 hours. An autopsy of the pilot’s remains was conducted by the Office of the Chief Medical Examiner, Northern Virginia District, Manassas, Virginia. According to the pilot’s autopsy report, his cause of death was thermal injuries and smoke inhalation, and his manner of death was accident. Mild coronary artery disease was present, with 30-40% narrowing of the right coronary artery by plaque, and 20-30% narrowing of the left main coronary artery and proximal left anterior descending coronary artery by plaque. Postmortem toxicological testing by the Virginia Department of Forensic Science measured carboxyhemoglobin at approximately 20% in iliac blood. Postmortem toxicological testing by the FAA Forensic Sciences Laboratory measured carboxyhemoglobin at 16% in iliac blood, and cyanide at 0.34 µg/mL in heart blood. FAA testing also detected diphenhydramine at a low level in iliac blood and at 16 ng/mL in urine. Alfuzosin, naproxen, and desloratadine were detected in iliac blood and urine. Valsartan was detected in urine and was not detected in iliac blood. Carboxyhemoglobin is formed when carbon monoxide binds to hemoglobin in blood, diminishing the blood’s ability to deliver oxygen to body tissues. Carbon monoxide is an odorless, tasteless, colorless, nonirritating gas that can be produced during hydrocarbon combustion. Carbon monoxide poisoning usually occurs by inhalation of smoke or exhaust fumes. Increasing levels of exposure may become impairing or incapacitating, progressing to death above carboxyhemoglobin levels of about 50% (or lower if other serious medical conditions exist). Cyanide is a fast-acting poison that interferes with cells’ ability to use oxygen. Cyanide may be produced as a byproduct of the combustion of nitrogen-containing polymers, which are found in a variety of goods including some plastics, upholstery materials, and synthetic rubbers. Cyanide exposure frequently occurs by inhalation during fires in which such goods are burning. Diphenhydramine is a sedating antihistamine medication widely available over the counter in multiple sleep aids and cold and allergy products. Diphenhydramine can cause cognitive and psychomotor slowing and drowsiness, and often carries a warning about driving and operating machinery. The FAA states that pilots should not fly within 60 hours of using diphenhydramine, to allow time for it to be cleared from circulation. In a typical living person, the elimination half-life of diphenhydramine is about 3-14 hours, and the concentration of the drug in plasma is about 1.3 times that in blood. Alfuzosin is a prescription alpha blocker medication commonly used to treat symptoms of an enlarged prostate. Naproxen is a non-steroidal anti-inflammatory medication available without a prescription and commonly is used for control of pain and fever. Desloratadine is a non-sedating prescription antihistamine medication that can be used to treat allergy symptoms and hives. Valsartan is a prescription medication that can be used to treat high blood pressure and heart failure. Alfuzosin, naproxen, desloratadine, and valsartan are not typically impairing. On December 3, 2023, about 1548 eastern standard time, a Beech C23 airplane, N76SB, was destroyed when it was involved in an accident near Midland, Virginia. The commercial pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. ADS-B track data revealed that the pilot departed from runway 15 at Warrenton-Fauquier Airport (HWY), Midland, Virginia, about 1308 and conducted three RNAV instrument approaches to Stafford Regional Airport (RMN) in Stafford, Virginia, and one RNAV instrument approach to Culpeper Regional Airport (CJR) in Culpeper, Virginia, before returning to attempt an approach and landing at HWY. According to information obtained from air traffic control, the pilot provided several PIREPs to Potomac (PCT) Terminal Radar Approach Control (TRACON) regarding cloud heights. The flight was cleared for the RNAV runway 33 approach to HWY with an intended full-stop landing. The pilot advised PCT TRACON that he intended to cancel his IFR clearance in the air once he descended below the clouds. ADS-B data revealed that the airplane descended toward runway 33, and track data was lost about 4,350 ft short of runway 33 and right of the runway centerline. The pilot made no distress calls over the radio during the approach. A witness who was hunting approximately 1 mile from the accident site reported hearing the accident. The witness reported that he did not hear any engine noises just before hearing the airplane impact the terrain. The accident was partially captured on a local surveillance camera about 0.5 miles from the accident site. In the video, the airplane was not visible; however, the airplane’s engine could be heard operating, followed by the sound of the airplane impacting trees, and a fireball could be seen in the distance. The airplane collided with 80-ft-tall hardwood trees on a 330° heading about 0.35 nautical miles east of the runway 33 threshold. There was a postaccident fire that consumed most of the forward fuselage and cockpit. The cockpit instruments were destroyed and no discernible instrument readings were found. The right wing separated during the impact with trees. The left wing remained partially attached to the fuselage and was folded under the cabin area of the fuselage. Flight control continuity was only partially established due to the extent of the thermal damage. The aileron control cable chains were wrapped in place around the control sprockets. The left direct cable was overload fractured at the point of the wing fracture. The control cables remained connected to the left wing aileron bellcrank. The right aileron control cables were fracture separated from the right aileron bellcrank. The control columns and wheels were consumed by fire. The elevator control cables were continuous from the cockpit yoke to the elevator. The rudder pedal torque tubes were partly consumed by fire, particularly in the area of the rudder control cable attach points. Portions of the rudder control cable cleave ends were observed still attached to the control cable ball ends. The rudder control cable was continuous from the cockpit to the rudder horns. The elevator trim control cables were continuous from the trim actuator to the cockpit. The position of the flap handle could not be determined. The majority of the airplane’s fuel system was consumed by fire. Both wing fuel tanks were breached and the fuel supply lines to and from the fuel selector valve were burned away near the valve. Both wing tank fuel pick-up screens were clear of any debris. The fuel strainer bowl was thermally damaged, and the strainer screen was exposed. The screen was examined and was found to be free of debris. Operation of the fuel selector valve was verified in the Left and Right positions, and the valve was free of obstructions. The engine remained attached to the airframe through the engine mounts, wires, cables, and hoses. The engine was impact and thermally damaged. The crankshaft was rotated manually, and continuity was established between the crankshaft, camshaft, connecting rods, and associated components. Cylinder compression and suction were observed on all four cylinders during