MIAMI – This week, the National Transportation Safety Board (NTSB) released the final report of the investigation into the Dynamic International Airways (2D) Flight 405 accident.
The probable cause was determined to be the separation of the fuel line due to missing lockwire.
The Boeing 767-200ER, N251MY, was taxiing to the runway when a significant fuel leak and fire occurred. There were 90 passengers, and 11 Crew on board.
On October 29, 2015, at 12:28 pm, 2D405 was being pushed back from the gate when the Flight Crew had noted that there was an anomaly with the fuel gauge about 20 minutes to departure.
A few minutes later, the aircraft was taxiing to the runway. Another aircraft reported to Air Traffic Control that there was a large amount of fluid leaking from the left wing of 2D405.
Less than a minute later, the left engine was on fire.
When alerted to the fire, the Flight Crew pulled the fire handle for the left engine. Within two minutes of the aircraft had stopped, the firefighting equipment arrived to put out the flames.
Passengers and Crew evacuated mainly through the front two doors and rear right door. While the Cabin Crew alerted the Flight Crew via the emergency signaling system in the cockpit, there was no response from the flight crew.
As per the Flight Attendant Manual, the Cabin Crew started the evacuation.
While the left engine had its fire handle pulled, the right engine was still running at the time of the evacuation. This meant that the first passengers who exited door 2R found themselves in the direct path of the engine exhaust.
The engine exhaust blew one passenger over, suffering serious injuries. There were other minor injuries among 21 other passengers.
There was no overwing evacuation. On the left side, there was fire, and the slide on the right side did not deploy.
The Fuel Line
The NTSB found that a fuel coupling on the left-wing fuel system had become separated. They also found no evidence of a safety lockwire in the compartment.
The Boeing aircraft maintenance manual requires the use of a lockwire on the fuel coupling.
Boeing recommended replacing these couplings, which the maintenance provider completed in 2012. They also conducted a general visual inspection in the zone in 2015. The aircraft flew 240 with the replaced couplings until the accident.
It was understood that the heat from the active engine was enough to cause the leaking fuel to ignite.
According to the NTSB Final Accident Report DCA16FA013, June 8, 2020, the probable cause of the incident was determined to be:
“… the separation of the flexible fuel line coupling and subsequent fuel leak due to the failure of maintenance personnel to install the required safety lockwire.”
“Contributing to the severity of the accident was the initiation of the evacuation before the right engine was shut down which led to the passenger’s injury.”