AIB releases report on four plane crashes
• Seeks prompt report of incidences
• NCAA to monitor engine replacement in sector
The Accident Investigation Bureau (AIB) has released another four reports on past air mishaps with various recommendations made to the Nigerian Civil Aviation Authority (NCAA) and concerned operators.
Besides, the AIB has redoubled its efforts to fast-track easy reportage of serious and minor incidences in the aviation industry with the launch of an application for both operators and the public.
The mobile app, launched in Lagos yesterday, is to avail better access to news and updates, enhance convenience and live reporting by eyewitnesses in the event of accidents or incidents. Pictures can also be uploaded on the app to assist greatly in investigations.
Meanwhile, the NCAA, in response to one of the AIB’s recommendations, is considering issuing an All Operators Letter (AOL) to make mandatory the issuance of notice on engine replacement in aircraft prior to the completion of the exercise. The rule is to curb negligence and mishap on the part of the engineering team.
According to the AIB report, on June 5, 2015, Aero Contractors Company of Nigeria Ltd scheduled commercial flight NIG181, a Boeing 737-500 aircraft with registration number 5N-BLE from Lagos to Kaduna, took off at 1828hours with 108 passengers and five crew members on board. The First Officer was the pilot flying. The flight operated on an Instrument Flight Rules (IFR).
The Air Traffic Control (ATC) cleared the aircraft for take-off and to climb and maintain Flight Level (FL) 350. Normal cabin rate of climb (300ft/min) was observed during the initial climb. During climb at approximately 23 minutes, the cabin altitude warning horn sounded and the cabin altitude warning light came on.
The Captain took control of the aircraft, passenger announcement was made and emergency descent initiated to an altitude of 10,000ft.
The flight diverted to Abuja with a distance of about 120nm to go. The aircraft made a safe landing in Abuja at 1932hrs and all passengers and crew disembarked normally and without injuries. The incident occurred at night.
The investigation, according to the Chief Executive Officer of the AIB, Akin Olateru, identified the following causal and contributory factors: “The inadvertent failure to discover that the Pressure Regulating Shutoff Valve (PRSOV) was in the ‘locked closed’ position after the engine change. And failure to recognise that the number two bleed pressure was zero after engine start and subsequent failure to monitor the pressurisation system during climb.”
The bureau, therefore, recommended that NCAA should ensure that the activities of flight operations and maintenance departments of Aero Contractors Company of Nigeria Limited are carried out in compliance with the Nig.CARs.
In the second incident, involving NCAT’s turboprop training aircraft, investigation submitted the causal factor as the decision of the crew to depart Nnamdi Azikiwe International Airport (NAIA), Abuja, with the knowledge of weather forecast, and failure to follow the guidance provided by the weather radar advisory to avoid the impending adverse weather.
Though the two occupants sustained minor injuries, AIB issued six safety recommendations, including more oversight on all private and special categories of aircraft in operation.
Olateru, who said the number was a partial fulfilment of his earlier promise to release a backlog of 27 reports that had been pending at AIB, said six more accident reports would be released by the first quarter of 2018.
