Negligence, human errors cause four air accidents – AIB

The Accident Investigation Bureau on Wednesday released four more air accident reports, having released six others in the last few months.
One of the reports was on the incident involving a Boeing 737-500 with registration 5N-BLE belonging to Aero Contractors Company of Nigeria Limited. The airplane was on a scheduled commercial flight from Lagos to Kaduna with 108 passengers and five crew members on board, with the incident occurring on June 5, 2015.
Others are on the accident involving the Nigerian College of Aviation Technology’s Socata TBM 850 aircraft near the Kaduna airport on May 21, 2013; Gitto Construczioni Generali Nigeria Limited’s Bell 407 helicopter accident at the Uyo airport on October 21, 2009; and the International Aviation College’s Diamond DA42 aircraft accident at the Ilorin airport, on August 18, 2014.
The Commissioner, AIB, Mr. Akin Olateru, said the accident involving Aero Contractor’s aircraft, which made the flight to be diverted to the Abuja airport, was caused by the pilot’s failure to discover that the PRSOV (Pressure Regulating Shutoff Valve) was in the ‘locked closed’ position after the engine change as well as failure to monitor the pressurisation system during the aircraft’s climb.
On the incident involving the NCAT, Olateru explained that the decision of the crew to depart the Nnamdi Azikiwe International Airport, 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 caused the accident.
The Uyo incident, according to him, was caused by improper maintenance of the oil system, which led to oil starvation and resulting in the failure of the No. 6, 7 and 8 bearings in the power turbine section of the engine, leading to power loss.
He added that the decision of the pilot to continue with the flight from Uyo to the Port Harcourt International Airport without identifying the cause of the transmission chip detector indication was also a major problem.
Olateru said the major cause of the IAC Ilorin incident was the failure of the pilot to adhere to the main wheel installation procedure.
He explained that recommendations had been made on the four incidents to the companies involved, the Nigerian Civil Aviation Authority and the aircraft manufacturers, and that appropriate actions had been taken.
According to him, on Aero’s incident, the AIB recommended that the NCAA should ensure that the activities of flight operations and maintenance departments of the airline are carried out in compliance with the Nigerian Civil Aviation Regulations.
“The NCAA’s response to Aero’s investigation was that due to the frequent engine changes, the authority is considering issuing an All Operators’ Letter requiring operators of aircraft to mandatorily inform it of any engine changes prior to accomplishment. This will enable the NCAA to monitor the processes,” he added.
Olateru said the AIB had published 10 reports this year, while 35 safety recommendations had been made, adding that the bureau was working on six more reports, which would be released in the first quarter of 2018.
“Our statutory obligation is to investigate air accidents and serious incidents, and by our safety recommendations, mitigate them in order to forestall reoccurrence,” he added.
He said the bureau had also launched a mobile application known as the AIB app, as part of strategies to reposition the agency and ensure its relevance on the international scene.
“The app will simplify the process of reporting incidents and accidents. The development of a mobile application is essential to our processes as it extends our relationship with users by providing better access to news and updates, convenience and live reporting by eye witnesses in the event of accidents or incidents, among others. Pictures can be uploaded on the app. This can assist greatly in investigations,” he said.