The Accident Investigation Bureau (AIB), has released preliminary report involving Vice-President Yemi Osinbajo ‘s AgustaWestland AW139 helicopter crash in Kabba, Kogi State which occured on February 2, 2019.
The report showed that Caverton Helicopters Limited did not conduct site survey of the landing field prior to this flight.
The helicopter experienced a hard landing on the right main landing gear and rolled over to the right after another helicopter with advanced party of the Vice-President raised huge dust after landing which blurred the vision of the crew ferrying Osinbajo and his team.
The Captain immediately shut the engines while the Co-Pilot shut off the fuel. The flight crew could remember executing the emergency landing procedures, which included switching off fuel, battery and generators.
But for the experience of the crew which shut fuel off and switched off battery and generator, the airplane would have been engulfed in fire on landing. That would have been disastrous for the occupants of the ill-fated aircraft.
Weather was ruled out as the cause of the accident which contradicted the position of the Managing Director of Caverton Helicopters, Capt. Josiah Choms who disclosed same day of the accident that the crash was caused by ‘bad weather’.
Weather report obtained by Nigerian Airspace Management Agency (NAMA), the prevailing weather at the stadium was good (CAVOK).
On February 2, 2019 at about 07:26 hour, an AgustaWestland (AW139) helicopter with nationality and registration marks 5N-CML owned and operated by Caverton Helicopters Limited departed Murtala Mohammed International Airport Lagos, for Nnamdi Azikiwe International Airport Abuja, to conduct a chartered VIP flight from Abuja to Okene via Kabba and then return to Abuja.
The report shows that the positioning flight to Abuja was uneventful. At about 13:46 h, the helicopter departed Abuja runway 22 for Kabba, Kogi State on a VIP chartered flight Nigeria 002 (NGR002), on a Visual Flight Rule (VFR) Flight Plan with 12 persons onboard, including the Vice President of the Federal Republic of Nigeria, his entourage and three crew members (Captain, Co-Pilot and an Engineer).
The fuel on-board was 1,268 kg. A squawk code of 1301 was given by the Air Traffic Control (ATC) for radar monitoring. The Captain was the Pilot Flying (PF) while the Co-pilot was the Pilot Monitoring (PM).
Reading out the report at AIB’s headquarters at the Murtala Muhammed Airport, Lagos, Commissioner AIB, Akin Olateru, an aircraft engineer said initial findings also shows that Caverton Helicopters Limited did not also carry out safety and risk assessment of the landing area prior to dispatch of the flight. The report equally hovered to land in a brownout condition.
A brownout is a condition generated during landing in a dry, sandy environment
According to Olateru, during the landing, at about 50 feet to touchdown, a heavy brownout enveloped the helicopter and the crew lost visual contact with the ground. 13.
According to the report, “The Co-Pilot called out radio altimeter 35, 30, 25, 20, 15 and no more. 14. At about 14:34 hour, the helicopter touched down hard on the right main landing gear and rolled over to the right. 15. The crew carried out Emergency Landing Procedures which included immediate engines shutdown, fuel shut OFF, battery switch OFF, and generators switch off”.
In its safety recommendation to the Nigerian Civil Aviation Authority (NCAA), the accident investigation bureau directed the NCAA to issue an advisory circular to all helicopter operators flying in Nigeria to be alert of the possibility and the effect of brownout, stressing that appropriate procedures should be put in place to mitigate its effect.
It also recommended that Caverton Helicopters Limited should ensure that flight operations are carried out in accordance with the company’s approved operations manual, vis-a-vis site survey and proper safety risk analysis to be done before dispatching any helicopter to unapproved landing pads.
The report indicated that the Flight Data Recorder (FDR) data indicated that the take-off and climb out phase was normal; and the helicopter levelled off at a cruising altitude of 5,000 feet flying with autopilot coupled.
During cruise at 14:20 hour, the Multi-Purpose Flight Recorder (MPFR) light came on indicating that the recorder had stopped recording and the Crew Alerting System (CAS) displayed FDR and CVR Fail.
Subsequently, the Caverton Helicopters Quick Reference Handbook (QRH) procedures were accomplished which advised that the flight should continue. The helicopter was monitored on Abuja Approach Radar until 55 NM to Kabba, when the helicopter began descent.
Further explaining the history of the flight before the crash, another helicopter, (Bell 412) with nationality and registration marks 5N-PEJ operated by the Nigeria Police Force (NPF) conveying the advance party, established radio communication with NGR002 just before the MPFR failed.
The police helicopter landed in the stadium at 14:30 hour ahead of NGR002. The crew of NGR002 stated that they sighted the stadium as a result of the brown dust generated by the downwash of the police helicopter main rotor. The crew further stated that the approach was normal.
After identifying the stadium, both flight crew members agreed on the selected landing spot within the stadium.
The NGR002 got into hover to land and at 50 feet above ground level, a brown-out set in. The crew lost visual contact with the ground and elected to use the Instantaneous Vertical Speed Indicator (IVSI) and Radio Altimeter (RAD ALT) to control the descent. The Co-Pilot began RAD ALT Callouts “35, 30, 25, 20 and 15”.
After the RAD ALT 15 Call-out, neither the Co-pilot nor the Captain could remember making or hearing further callouts. At about 14:34 h, the helicopter experienced a hard landing on the right main landing gear and rolled over to the right.