The Nigerian Safety Investigation Bureau (NSIB) has released a preliminary report detailing extensive damage to an Arik Air aircraft following an in-flight engine anomaly.
On February 11, an Arik Air Boeing 737-700 aircraft operating a Lagos–Port Harcourt flight diverted to Benin Airport after the crew “heard a loud bang from the left engine.”
The aircraft, operating flight W3-740 with registration 5N-MJF, was descending into Port Harcourt International Airport, Omagwa, when the incident occurred.
The aircraft had seven crew members and 80 passengers on board, bringing the total number of occupants to 87.
According to the report, the aircraft was climbing from flight level (FL) 260 to FL 290 when the crew heard a loud bang followed by excessive vibration from the number one (left) engine.
A post-occurrence inspection conducted by NSIB on the aircraft at the apron of Benin Airport revealed significant damage to the engine and other parts of the aircraft.
NSIB said the engine inlet cowling was missing, while the number six fan blade of the engine had broken off, with only the root remaining attached.
“The remaining 23 fan blades were all chipped and damaged. The inboard and outboard engine cowling covers were folded upward, exposing the engine accessories, while the engine-driven pump (EDP) clamp was found loose,” the report said.
“A deep cut about 0.6 inches long on the containment case was observed at the 2 o’clock position. A long, deep cut about 7.2 inches on the containment case was observed at the 1 o’clock position. Cracks were also observed on the exterior of the engine containment case.”
The NSIB said the outlet guide vanes (OGV) at the five, six, and seven o’clock positions were missing, while the engine-driven pump and exhaust assembly sustained visible damage.
The bureau also found that the engine oil tank filler cap was missing and the anti-ice duct was broken, with part of it missing.
Other affected components included the left-hand vortex generator and the integrated drive generator (IDG) oil cooler, according to the bureau.
“There were dents and punctures at various locations on the airframe, damage to the inner and outer thrust reversers, cuts on the left wing leading edge, and damage to the left-wing air-conditioning bay fairing,” the NSIB added.
The bureau said more damage was recorded on the left horizontal stabiliser leading edge and the upper surface of the stabiliser, which had large cuts.
The report also showed that the vertical stabiliser leading edge and the rudder surface were damaged.
The report classified the aircraft as substantially damaged, noting that no injuries were recorded among the occupants.
Despite the incident, the NSIB said communication between air traffic control and the flight crew remained effective.
The bureau added that post-occurrence medical examinations were conducted on the flight crew, and they tested negative for alcohol, drugs, and other psychoactive substances.
NSIB said further investigative actions will include metallurgical examinations of the broken number six engine fan blade root and the remaining 23 fan blades, as well as a teardown of the number one engine as part of the ongoing investigation.
