HISTORY OF FLIGHTOn June 17, 2024, about 1415 eastern daylight time, an experimental amateur-built Vans RV-6A airplane, N715PA, was substantially damaged when it was involved in an accident near Methuen, Massachusetts. The private pilot was fatally injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot’s friend, the pilot planned to practice takeoffs and landings in the airport’s traffic pattern. A review of air traffic control communications and radar data revealed the airplane departed runway 23 at the Lawrence Municipal Airport (LWM), Lawrence, Massachusetts, about 1411. After takeoff, the airplane climbed to 1,650 ft mean sea level (msl) before it made a wide right turn to enter the downwind leg of the traffic pattern (see figure 1). About 1411, an air traffic controller cleared the pilot to land, and the pilot acknowledged. Less than 1 minute later, the pilot said he was having a “problem”, and the controller cleared him to land on any runway. The pilot transmitted “oh, oh”, and there were no further communications from him. Figure 1. ADS-B flight track data for the entire flight (yellow line) with the wreckage area at the accident site annotated (orange square). Several witnesses reported that they thought the airplane was experiencing engine trouble after it took off. One witness was outside his office when he heard the airplane departing. The engine was at “full throttle” before it abruptly stopped. The witness said the airplane leveled and made a right turn (north to east) at an altitude of about 1,500 to 2,000 ft msl. He thought the pilot was having a fuel issue or he was practicing a simulated “engine out” in the traffic pattern. He never heard the engine restart. The witness said the airplane looked “in control” the entire time before it disappeared from his view behind trees and buildings. Another witness was working near the airport when he heard the airplane’s engine sputter and “quit” before it reached traffic pattern altitude. Less than 1 minute later the witness heard the engine restart, sputter and quit again. The airplane was flying east toward the Merrimack River before it disappeared from his view. A helicopter pilot, who had just landed at LWM, observed the airplane on downwind in a controlled descent over the Merrimack River. He told the controller that the airplane was not going to make it back to the airport. The helicopter pilot departed and located the airplane in the river. Fuel and engine performance data were recovered from the from the airplane’s Electronics International MVP-50 engine monitor, and showed that shortly after takeoff, the engine’s fuel pressure began to decrease to 0 psi. This was followed by a total loss of engine power shortly thereafter. The data indicated that when the pilot first started the engine prior to takeoff, the indicated fuel quantities were 18.6 gallons of fuel in the left tank, while the right fuel tank was empty. The engine monitor recorded data as far back as June 2021, and indicated the airplane was last refueled in July 2022, and the last flight prior to the accident flight was April 20, 2023. Prior to the accident flight, there were a number of power cycles and a few engine runs during which time fuel was used exclusively from the right fuel tank. By April 2024, the right tank was nearly empty, until the accident flight when it indicated it was completely empty. PERSONNEL INFORMATIONThe pilot, age 80, held a private pilot certificate for airplane single-engine land and repairman experimental aircraft builder. His most recent Federal Aviation Administration (FAA) third-class medical certificate (without limitations) was issued on October 5, 2023. At that time, the pilot reported 295 total hours of flight experience. The pilot’s flight logbook was not available for review. AIRCRAFT INFORMATIONThe airplane’s most recent annual inspection, along with the engine and propeller condition inspections, were completed by the pilot on May 7, 2023. No airframe or tachometer time was listed. There was a partially completed condition inspection report found with the maintenance records that was dated 2024. AIRPORT INFORMATIONThe airplane’s most recent annual inspection, along with the engine and propeller condition inspections, were completed by the pilot on May 7, 2023. No airframe or tachometer time was listed. There was a partially completed condition inspection report found with the maintenance records that was dated 2024. WRECKAGE AND IMPACT INFORMATIONThe airplane came to rest inverted on a sandbar in the Merrimack River in about 3 ft of water. There was no postimpact fire. The airplane was completely intact but sustained impact damage to the outboard section of the left wing, the canopy, and the engine cowling. The entire cockpit area, including the panel was undamaged. Flight control continuity was confirmed for each flight control surface to the cockpit. The engine and the two-blade propeller were relatively undamaged. Some longitudinal scoring was noted on the spinner. The cowling was removed to facilitate an engine exam/test-run. The engine’s crankshaft was rotated manually via the propeller. As the crankshaft was rotated, compression and suction were confirmed on each cylinder. Continuity for the throttle, mixture and carburetor heat cables was confirmed from the cockpit to the engine. The throttle lever was at the full throttle position, and the mixture lever was at the full rich position, which matched the control positions in the cockpit. Examination of the airplane’s fuel system revealed there were no breaches or evidence of preexisting leaks anywhere in the system. There was a 19-gallon fuel tank in each wing. About 18 gallons of 100LL fuel was drained from the left-wing tank. Some water was observed in the fuel. Less than a gallon of yellow/brown colored water was drained from the right tank and no fuel was observed. The fuel selector was found positioned to the right tank. The firewall fuel strainer was damaged, and a few ounces of liquid (half fuel, half water) were drained from the strainer bowl. The carburetor was intact. About 4.5 ounces of water and about 1 ounce of fuel were drained from the carburetor bowl. The fuel finger screen was absent of debris. The engine was test-run on the airframe using the airplane’s existing fuel system with the fuel selector remaining on the right tank. The engine started and ran without interruption through its full power band. Both magnetos were tested with the engine running. The engine ran rough when the right magneto was tested. The reduction of engine rpm observed when only the left magneto was selected was normal. Examination of the engine and fuel system revealed no evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. MEDICAL AND PATHOLOGICAL INFORMATIONThe Commonwealth of Massachusetts Office of the Chief Medical Examiner performed an autopsy of the pilot’s remains. According to the autopsy report, his cause of death was drowning and blunt force injuries of the head/neck and torso, and his manner of death was accident. The autopsy identified some evidence of hypertensive and atherosclerotic cardiovascular disease. His heart was described as enlarged, with mild narrowing of the coronary arteries by plaque. There was moderate plaque in the aorta. The kidneys exhibited some tissue changes of the type that can be seen in chronic high blood pressure. The pilot’s postmortem toxicological testing by the FAA Forensic Sciences Laboratory detected glipizide, pioglitazone, losartan, atorvastatin, and tamsulosin in heart blood and liver tissue. Glucose was measured at 965 mg/dL in urine and was not detected in vitreous fluid. Blood HbA1c was 7.4%. HbA1c is an indirect measure of a person’s average blood glucose over approximately the preceding 3 months. An HbA1c of 6.5% or higher diagnosis diabetes. Urine glucose does not directly reflect blood glucose but may increase due to high blood glucose and/or altered kidney function. Vitreous glucose generally is lower than blood glucose during life and decreases early after death. The FAA Forensic Sciences Laboratory considers postmortem glucose levels to be abnormal above 100 mg/dL in urine or above 125 mg/dL in vitreous fluid. Glipizide and pioglitazone are prescription oral medications commonly used in the treatment of diabetes. Glipizide is not typically impairing but may pose some risk of causing low blood glucose, symptoms of which may adversely affect concentration and performance. Pioglitazone is not typically impairing but can increase the risk of low blood glucose when used in combination with glipizide. In the US, pioglitazone also carries a boxed warning about increasing the risk of heart failure. For pilots who report using glipizide and pioglitazone to treat diabetes, FAA medical certification is subject to case-by-case FAA review of the underlying condition and response to treatment. Losartan is a prescription medication commonly used to treat high blood pressure. Atorvastatin is a prescription medication commonly used to help control cholesterol and reduce cardiovascular risk. Tamsulosin is a prescription medication commonly used to treat symptoms of a large prostate. Losartan, atorvastatin, and tamsulosin are not typically impairing. At the time of the pilot’s last third-class FAA medical examination in October 2023, 8 months prior to the accident, he did not report the use of any medications or any active medical conditions and was issued a third-class medical certificate.