Flight Crew’s Improper Fuel Management, Which Resulted In The Airplane’s Right Engine Being Starved Of Fuel 

Location: Claxton, Georgia Accident Number: ERA23FA274
Date & Time: June 25, 2023, 12:32 Local Registration: N7240Y
Aircraft: Piper PA-30 Aircraft Damage: Substantial
Defining Event: Fuel starvation Injuries: 3 Fatal
Flight Conducted Under: Part 91: General aviation - Instructional

Analysis: The pilot, flight instructor, and a pilot-rated passenger had planned an instructional flight in the multiengine airplane to prepare the pilot for a proficiency check with an FAA inspector the following day. They were not able to fuel the airplane before departure and flew to a nearby airport to obtain fuel before the instructional flight; however, while refueling the airplane, the fueling equipment malfunctioned and they obtained less than 1 gallon of fuel. They subsequently departed, and the airplane impacted trees and terrain less than ½ mile from the end of the runway.

ADS-B data showed that, during the accident flight, the airplane was in close proximity to the ground just beyond the departure end of the runway for about 8 seconds. The altitude data did not depict an appreciable climbing trend during that time. The distance between the final ADSB position and the accident site was less than 700 feet, and the track line between these two points was about 30 degrees right of the departure runway’s heading.

The results of toxicological testing revealed the pilot had used alprazolam and methadone. Both medications have the potential to impair cognitive and motor function. However, because measured levels of the drugs in cavity blood cannot be used reliably to predict effects, whether the pilot was experiencing impairing effects from alprazolam and methadone use could not be determined.

The results of toxicological testing revealed the flight instructor had used warfarin. Reviewed records did not indicate the reason for the flight instructor’s warfarin use. Warfarin itself is not typically impairing; however, some underlying conditions for which it is used increase the risk of sudden impairing medical events such as stroke or unstable arrhythmia. There was no autopsy evidence that such an event occurred, but such an event may not leave reliable autopsy evidence.

Examination of the wreckage revealed that, while some fuel was present in the right wing’s auxiliary fuel tank, no quantifiable fuel was found in the right main fuel tank. Some fuel was observed draining from the left-wing fuel tanks during recovery from the accident site. The left engine fuel selector was found set to the left main tank, while the right fuel selector was found positioned between the auxiliary and off positions. Additional examination of the fuel system revealed that the components associated with the right engine and its fuel supply were generally absent of fuel, while the left engine’s fuel system components contained trace amounts of fuel. The left engine’s propeller displayed signatures that were consistent with powered rotation at impact, while the right engine’s propeller displayed no evidence of powered rotation at impact. Neither engine displayed evidence of a preimpact mechanical malfunction or failure. The landing gear were found extended.

While there was not sufficient evidence available to determine the airplane’s fuel state before the accident takeoff, given that the flight crew’s attempt to fuel the airplane was unsuccessful, it is likely that they departed with less fuel than anticipated, and that they may have been attempting to use fuel from the auxiliary fuel tank during the takeoff, contrary to the manufacturer’s guidance. It is also possible that the pilots were manipulating the fuel selector in response to a loss of engine power, which resulted in the fuel selector’s as-found position. 

Regardless, the lack of fuel found in the right engine fuel system components downstream of the fuel selector suggest that the right engine lost engine power due to fuel starvation. Additionally, because the airplane had been flying for fewer than 10 seconds before impact, and given that the landing gear remained extended and the right propeller remained unfeathered, the flight crew likely did not configure the airplane quickly enough for successful, sustained single-engine flight before it impacted trees and terrain. 

Probable Cause and Findings: The National Transportation Safety Board determines the probable cause(s) of this accident to be -- The flight crew’s improper fuel management, which resulted in the airplane’s right engine being starved of fuel and its subsequent total loss of power.

FMI: www.ntsb.gov