On 13th February, 2018 at about 22:51 h, an Airbus A330-223 aircraft with nationality and registration marks N858NW owned and operated by Delta Air Lines Inc. departed Murtala Muhammed International Airport Lagos, Nigeria for Hartsfield-Jackson International Airport, Atlanta, Georgia, United States of America, as a scheduled flight DAL55, operated on an Instrument Flight Rules (IFR) flight plan. The flight had 234 persons on board comprising two captains and two first officers; nine cabin crew members and 221 passengers including two infants.
During climb, at 22:52 h and at an altitude of about 1,700 ft, the fire warning on engine No. 1 activated (ON indication). At 22:52:25 h, the crew contacted ATC, declared an emergency, and requested a return to the airport and for the emergency services to be on stand-by. The aircraft turned back to the airfield.
At 22:53:50 h, DAL55 was cleared for landing on runway 18R. At about 22:59 h, the aircraft landed safely.
The Airport Rescue and Fire Fighting Services (ARFFS) reported observing a fire in engine No. 1 and attempted to extinguish it. ATC confirmed there was fire at the tail end of the engine No.1 exhaust pipe, the Captain then ordered an evacuation. The passengers were evacuated using the emergency slides on the Right-Hand side of the aircraft. One passenger was seriously injured, and 11 passengers sustained minor injuries during the evacuation.
The incident occurred at night.
The investigation identified the following Causal and Contributory factors:
An overtemperature condition and localized fire within the No. 1 engine cowling triggered a fire warning. The overtemperature and fire were caused by the ignition of fuel from a hairline crack on the fuel manifold supplying fuel nozzle 1.
The fuel manifold cracking can be attributed to high vibratory stresses due to coupling of an acoustic combustor mode and a fuel manifold structural mode.
One Safety Recommendation was made.