The Commissioner, Accident Investigation Bureau, AIB, Mr. Akin Olateru has attributed the crash of Vice President Yemi Osibanjo’s helicopter crash in Kogi State on 2nd February, 2019 to ‘brownout’.
He said the brown out caused the crew to lose visual as well as misjudge distance from the ground to air.
At the release of the four final accident Investigation Reports, during a virtual news conference, the AIB commissioner said the Bureau was able to issue two safety recommendations with regards to the Augusta crash of 2nd February, 2019, including one to the NCAA and another to the Office of the National Security Adviser.
While listing the causal and contributory factors of the crash, the AIB boss said the flight crew encountered a brownout condition during hovering to land, which led to the loss of external visual references, spatial disorientation and loss of situational awareness resulting in a misjudgement of distance and ground clearance.
Mr. Olateru listed the contributory factors to include inappropriate landing technique used, non-adherence to company procedures for known or anticipated brownout condition during landing and lack of risk assessment, limited landing site preparation and planning prior to commencement of the flight.
The safety recommendations urged the Nigeria Civil Aviation Authority, NCAA to conduct a Safety Management System (SMS) audit of Caverton Helicopters.
“The SMS audit by the NCAA should ensure that Caverton Helicopters has implemented the Immediate Safety Recommendation 2019-003, the NCAA All Operators Letter (FSG 002), and the recommendations documented in the Caverton Helicopters internal SMS investigation of this accident.
It also says that the NCAA audit should also ascertain that the Caverton Helicopters internal SMS processes in the maintenance activities require the establishment of the reasons/causes of equipment failure/malfunction (reference is made to the failures of the Multi-Purpose Flight Recorder (MPFR).
Other accident reports released includes incident involving an AeroContractors Bombardier Dash 8-Q-400 with registration 5N- PBU and the two International Aviation College, IAC aircraft Diamond DA-42 5N-BNH and Diamond DA-40 aircraft Registration Marks 5N-BRM which occurred both on Runway 23, ilorin International Airport.
According to the AIB, the Aerocontractor aircraft, while cruising at FL240, 80 NM inbound Lagos from Port Harcourt, experienced bluish smoke which gradually increased in density within the cabin.
“The smoke progressed into the cockpit. The lavatory smoke detector aural warning activated, and the AFT baggage light illuminated on the Fire Panel but there was no burning smell perceived.”
It identified causal factor as engine oil leaked onto a hot surface of the engine causing fumes which mixed with the engine bleed air supply to the air conditioning system, resulting in smoke in the aircraft cabin, cockpit and lavatory/ cargo compartments.
The AIB says two Safety recommendations made urged Aero Contractors Company of Nigeria Limited to ensure that Cockpit and Cabin Crew are alive to their responsibilities during emergencies vis-à-vis establishing effective two-way communication.
“While the second, Safety Recommendation 2019-025 : Nigerian Civil Aviation Authority should ensure that operators utilize the New Oil Analysis Technology made available by Pratt & Whitney Canada in order to identify impending failure of the carbon seals on PW150A engines that are yet to comply with SB 35342R1.”
While it issued 5 recommendations for the IAC incidents both for the NCAA and the College.
According to the commissioner safety recommendations for Diamond DA-42 5N-BNH are: “Safety Recommendations 2019-026: NCAA should intensify its oversight on International Aviation College (IAC) and ensure that it adheres strictly to the use of Checklists and appropriate procedures during all training sessions and phases of flight.”
Iremide Jonathan