- Location: Clinton, Michigan
- Accident Number: CEN24FA215
- Date & Time: June 10, 2024, 13:11 Local
- Registration: N1039X
- Aircraft: Piper PA28
- Aircraft Damage: Substantial
- Defining Event: Fuel starvation
- Injuries: 1 Fatal, 1 Serious
- Flight Conducted Under: Part 91: General aviation - Instructional
https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/194430/pdf
https://data.ntsb.gov/Docket?ProjectID=194430
On June 10, 2024, about 1311 eastern daylight time, a Piper PA-28-140 airplane, N1039X, was
substantially damaged when it was involved in an accident near Clinton, Michigan. The flight
instructor was fatally injured, and the student pilot sustained serious injury. The airplane was
operated as a Title 14 Code of Federal Regulations Part 91 instructional flight.
The flight instructor and student pilot were conducting an instructional flight in the singleengine airplane. ADS-B data and an NTSB performance study showed that, after completing
training maneuvers south of the departure airport, there was a possible reduction in engine
power. The flight instructor contacted air traffic control to return to the airport, but did not
report any difficulties. Shortly after, the airplane was on a heading toward the airport in a
descent consistent with the best glide prescribed by the airplane manufacturer’s Pilot’s
Operating Manual. The airplane then turned about 270° to the left toward a local road and field,
consistent with the pilots maneuvering for a forced landing. While about 200 ft above ground
level (agl) and at an airspeed higher than the wings-level, flaps-retracted stall speed, the
airplane began a right turn away from the road. The wreckage and impact signatures, including
initial right wingtip contact followed by nose impact, were consistent with a loss of airplane
control while maneuvering at a low altitude during the forced landing.
Postaccident examination of the airframe and engine revealed no evidence of any preimpact
mechanical malfunctions or failures that would have precluded normal operation. The
examination also showed that the right fuel tank was intact and there was no evidence of
blighting or moistened soil beneath the right wing at the accident site that would indicate fuel
leaking from the wing tank. The left fuel tank was intact and contained some amount of usable
fuel after the accident. In addition, the left fuel cap was secure and intact, and no water was
detected in the fuel. The fuel selector handle and valve were found between the Left Tank and
Off positions, which would have prevented fuel flow. The entire fuel system forward of the fuel
selector contained either no or trace amounts of fuel.
Fuel records and the airplane’s flight history indicated that the airplane had been fueled to 36
gallons (18 gallons per fuel tank) two days before the accident flight. Only one 1.2-hour flight was completed after the airplane was refueled and before the accident flight. At an estimated
fuel consumption of 7.6 gallons per hour (gph) and assuming the fuel was evenly distributed
between the tanks, this would have resulted in 27 total gallons for the accident flight when it
departed the airport (13.5 gallons per fuel tank). Fuel calculations suggest that the engine was
operated between 60 and 75% power during the accident flight, consistent with a fuel
consumption rate between 6.8 and 8.4 gph. Assuming the flight departed with evenly
distributed fuel tanks, this fuel consumption for the 1.7-hour accident flight is consistent with
the airplane having been operated on one fuel tank for the entire accident flight was completed after the airplane was refueled and before the accident flight. At an estimated
fuel consumption of 7.6 gallons per hour (gph) and assuming the fuel was evenly distributed
between the tanks, this would have resulted in 27 total gallons for the accident flight when it
departed the airport (13.5 gallons per fuel tank). Fuel calculations suggest that the engine was
operated between 60 and 75% power during the accident flight, consistent with a fuel
consumption rate between 6.8 and 8.4 gph. Assuming the flight departed with evenly
distributed fuel tanks, this fuel consumption for the 1.7-hour accident flight is consistent with
the airplane having been operated on one fuel tank for the entire accident flight.
The lack of fuel in the downstream fuel system components, the fuel selector valve’s as-found
position, the remaining usable fuel in the left tank, and the lack of evidence of fuel leakage or
contamination were consistent with a total loss of engine power due to fuel starvation. It is
likely that, after the selected fuel tank was depleted, the fuel selector was inadvertently moved
past the Left Tank detent toward the Off position during an attempt to restore engine power,
which prevented fuel in the left tank from reaching the engine. The fuel selector was located
on the left side of the cockpit, next to the student pilot’s left leg. The student pilot did not recall
the flight or accident sequence. Therefore, the investigation could not determine when the fuel
selector was moved or which occupant moved it.
The flight instructor’s autopsy findings revealed some evidence of heart disease that increased
the risk of an impairing or incapacitating cardiac event; however, there was no autopsy
evidence that such an event occurred. Toxicology results also indicated that the flight
instructor had used a cannabis product. The measured levels of delta-9-THC and its
metabolites indicated a possibility that, at the time of the accident, the instructor pilot may
have been experiencing acute psychoactive effects of cannabis. However, delta-9-THC levels
as high as those found in this case may persist well beyond the time window of acute
psychoactive effects in frequent cannabis users. Whether the pilot was a frequent cannabis
user is unknown. Accordingly, the toxicology results alone do not establish whether the pilot
was experiencing significant cannabis-related cognitive or psychomotor impairment at the
time of the accident or during preflight preparations.
A long-lived non-psychoactive metabolite of delta-9-THC was detected in the student pilot’s
blood, indicating that he likely had used a cannabis product sometime in the days before the
accident. FAA testing did not detect delta-9-THC or psychoactive metabolites of delta-9-THC in
his blood collected about 1.7 hours after the accident. These toxicology results provide no
specific evidence that the student pilot was experiencing impairing cannabis effects at the
time of the accident or during preflight preparations.
Therefore, the available evidence was insufficient to determine whether impairment
contributed to the accident.
- Probable Cause: The flight instructor’s failure to maintain airplane control while maneuvering for a forced landing. Contributing to the accident was the student pilot’s or flight instructor’s inadvertent positioning of the fuel selector valve between the Left Tank and Off positions, which resulted in fuel starvation and a total loss of engine power. Also contributing to the accident was the flight instructor’s inadequate fuel monitoring.
