Icelandic investigators have discovered an incorrectly-fitted fuel-line coupling on an Air Atlanta Icelandic Boeing 747-300 which was severely damaged by an engine fire shortly after landing at Dhaka in Bangladesh.
The aircraft had been operating for Saudi Arabian Airlines and, on 25 March this year, had landed on Dhaka Zia International Airport's runway 14 following a flight from Medina.
While exiting the runway the crew received a fire indication for the inboard starboard Pratt & Whitney JT9D engine. Attempts to extinguish the fire were unsuccessful and the crew shut down the engines and ordered an evacuation.
Only minor injuries were sustained among the 309 passengers and 19 crew members but the Icelandic air accident investigation board Rannsoknarnefnd Flugslysa (RNF) says the jet was "damaged beyond economic repair" by the blaze.
Inspection of the affected area revealed that a main fuel-line coupling, at the entry point to the front spar of the engine, was missing a retaining ring and that an accompanying O-ring was not in the correct place on the fuel line.
"It is considered that the O-ring was not working to seal as it should," says RNF, adding that inspectors saw fuel leaking from the coupling.
Maintenance logs show that the coupling was opened, and the O-rings replaced, during a C-check on 27 August last year.
Malaysia Airlines' maintenance centre is assisting the inquiry, states RNF: "Investigation is focusing on maintenance issues and procedures for the replacement of O-rings on the aircraft fuel system."
The aircraft involved, registered TF-ARS with serial number 22996, was a 25-year old example.
Saudi Arabian Airlines is a strong Air Atlanta 747 customer. In June it agreed a long-term wet-lease agreement for a 747-300 and has also taken leases on two 747-200 freighters, bringing its Air Atlanta-operated 747 fleet to six aircraft.
Source: Flight International
