Improper Installation Of The Fuel Line That Connected The Fuel Pump To The Four-Way Distributor

Location: Seffner, Florida Accident Number: ERA24LA163
Date & Time: April 4, 2024, 15:37 Local Registration: N469JA
Aircraft: Evektor-Aerotechnik A S Harmony LSA Aircraft Damage: Substantial
Defining Event: Sys/Comp malf/fail (non-power) Injuries: 1 Serious, 1 Minor
Flight Conducted Under: Part 91: General aviation - Positioning

Analysis: The airplane was on the final leg of a flight to reposition it to its home base. This was the fourth flight since the airplane had been reassembled after it was manufactured, disassembled, and shipped. The pilot reported a normal takeoff, and during the initial climb the airplane performed normally. Upon reaching 2,200 ft mean sea level (msl), the airplane lost all engine power. The pilot turned back toward the airport and attempted to restart the engine multiple times without success. At 800 ft msl, the pilot deployed the whole airplane parachute system. The airplane descended under the parachute canopy until it impacted a tree, became inverted, and impacted the ground. The impact resulted in substantial damage to the  fuselage, vertical stabilizer, and both wings.

A postaccident examination of the airplane revealed that the fuel line going from the electrical fuel pump outlet to the four-way distributor was disconnected at the four-way distributor and was leaking fuel. The factory-installed clamp remained attached to the disconnected fuel line and was observed to be further down the fuel line than the other fuel lines that  remained attached to the four-way distributor. If the fuel line was seated properly, the clamp would have only been at the last ridge on the fitting. After examining the fuel line, the line was reinstalled onto the four-way distributor, and a new clamp was installed. An engine test run was performed, and the engine operated normally at all rpm settings except for idle, which was to be expected due to the propeller blades having been shortened to facilitate the test run. Except for the disconnected fuel line, no anomalies or mechanical failures were found with the airframe or engine that would have precluded normal operation of the engine.

Given this information, it is likely that during the climb the fuel line slipped off the four-way distributor valve and starved the engine of fuel. This is consistent with, and a likely result of, the fuel line and clamp being installed too low on the four-way distributor valve fitting, which resulted in the line being able to slide off the fitting during engine operation. There were no logbook entries documenting that the fuel line or the four-way distributor valve had been adjusted or reinstalled since the airplane was manufactured; however, there were minor differences between the condition of the fuel system as found after the accident vs. the condition of the system as documented by pre-delivery photographs taken by the airframe manufacturer. Given the lack of maintenance documentation, it could not be determined when any maintenance, modification, or other alterations of the fuel system could have occurred between when the airplane was manufactured and the accident flight.

Probable Cause and Findings: The National Transportation Safety Board determines the probable cause(s) of this accident to be -- The improper installation of the fuel line that connected the fuel pump to the four-way distributor, which resulted in fuel starvation when the line became disconnected.

FMI: www.ntsb.gov