Louis Ibah

The Accident Investigation Bureau (AIB) over the week released the final report on what led to the crash of the Associated Airlines aircraft, an Embraer 120ER with registration number 5N-BJY, on October 3, 2013 in Lagos.

The AIB report said the aircraft was destroyed by the impact of the crash and the post-crash fire that engulfed it. Of the 20 passengers on board the aircraft, 16 of them died while four survived. The AIB linked the crash to human errors on the part of the pilots and regulatory officials from the Nigerian Civil Aviation Authority (NCAA).

The report reinforces the thinking within the industry that 98 per cent of air accidents are caused by human errors and not necessarily the airworthiness of the aircraft. The report relied on recordings of conversations on the black-box between the chief pilot, co-pilots, engineer on board the aircraft as well as physical examination of the wreckage of the aircraft.
Synopsis

According to the AIB report, on  October 3, 2013, the Embrear aircraft, which was on a charter flight to convey the remains of former Ondo State Governor, Dr. Olusegun Agagu, as well as friends and family members was scheduled to depart Lagos for Akure on an Instrument Flight Rules (IFR), meaning the aircraft crew were not to rely on visual aids to operate the flight but were to be guided by instruments on the aircraft and from the control tower.

The Captain was the Pilot Flying (PF) and the First Officer (or co-pilot) was the Pilot Monitoring (PM) the flight. The AIB report said the flight into destruction started at 9.03am when the co-pilot established radio communication with Lagos Airport Ground Control and requested for engine start on the twin-engine aircraft.

The crew started engine number two first and followed it up by igniting engine number one.  The first problem with the flight started with disagreements among crew on the state of engine number one. Aircraft, just like cars, are built with indicators that show the performance of various parts, and they also warn about dangers ahead. Once engine number one was ignited, the co-pilot  noticed that the engine torque indicator was stuck at 76 per cent meaning that all was not well with the engine.

It should have been 100 per cent. The co-pilot therefore invited the engineer who was a crew member on board the aircraft into the cockpit to ascertain the job done on the Electronic Engine Control (EEC) tests to be sure that they got accurate readings from the indicator. But the engineer said he could not ascertain the job as he was not part of the team that worked on the aircraft. The engineer then requested that the co-pilot test the electronic engine control again to be sure it was working, but the pilot responded that this had been done several times. Nonetheless, the co-pilot repeated the test in the presence of the engineer, the reading did not change either. It was at this stage that a decision should have been taken by the crew to abort the flight and fix whatever problem that was associated with the engine. But this was never done.

Instead, at 9.20am, the co-pilot called the control tower and requested for clearance for take-off. The AIB report said that during the taxi for take-off, the crew continued with further discussions on the state of the aircraft, but without referring to any document considering that the torque indicator remained stuck at 76 per cent. The crew sensed danger but opted to risk the flight instead.

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At 9.29am, the aircraft received its final nod from the control tower to take-off on runway 18L. The wind was calm. However, as the co-pilot set power to commence the take-off there was an aural warning, which consisted of three chimes followed by “take-off flaps”. The aural warning changed after a few seconds to “take-off flaps…auto feather” The AIB said in its investigations, it discovered that after take-off power was set, the flap position did not agree with the selection. The aircraft as a mechanical and electronic device was doing its function of alerting the crew of danger, but they just didn’t heed the warning.

The co-pilot then noticed that the second propeller of the aircraft was rotating very low and raised concerns.  He was similarly concerned that in addition to the warnings from the engine and flaps, the aircraft thrust required to airlift it into the comfortable cruising altitude was slow and he advised the pilot-in-command  to abort the take-off. If that was done, the crash would have been avoided.

However, the pilot-in-command opted to go ahead. After lift-off, the co-pilot cautioned “gently” and called out to the captain-in-command “aircraft not climbing” and almost immediately cautioned “don’t stall”. It was a desperate call on the chief pilot to do all he could to ensure that the aircraft keeps climbing and doesn’t stall – suddenly stops working. At this point, the stall warning sounded in the cockpit and the co-pilot advised the pilot-in-command to lower the nose of the aircraft a bit.

A few seconds after, the pilot-in-command requested “full power” and the co-pilot maintained that the aircraft was no longer climbing. Thereafter, the aircraft, which had attained an altitude of 118 feet, drifted to the right and crashed immediately in a nose-down position with a steep roll to the right. The accident occurred at about 9.30am as the aircraft crashed into the Joint Users Hydrant Installation (JUHI), close to the airport, with the landing gears in the down position. The aircraft was destroyed by the impact of the crash and post-crash fire. There were 16 fatalities and four serious injuries.
Causal factors

In its summary of the report, the AIB blamed the decision of the crew to continue the take-off despite the flaws and warnings on the abnormalities on the propeller and engine. It also linked the crash to the decision of the pilots to perform a low altitude stall as a result of low thrust at start of roll for take-off from engine number two, which was caused by an undetermined malfunction of the propeller control unit.

The AIB also faulted the decision of the pilots to continue the take-off with flap configuration warning and auto- feather warning at low speed. “Poor professional conduct of the flight crew, inadequate application of Crew Resource Management (CRM) principles, poor company culture, inadequate regulatory oversight by officials of NCAA – all these human factors led to crash of the Associated Airlines aircraft,” AIB said.

Pilots incompetence
The AIB also queried the competence of the pilots, noting that “it was the pilot-in-command that conducted the last proficiency test on the co-pilot and that there was no documented evidence to substantiate that the pilot-in-command was an NCAA authorised type-rated instructor or examiner to certify the co-pilot.”

“No evidence was also available to the AIB that he fulfilled any of the required crew checks in 2013 including the Crew Resource Management (CRM) training which certifies him fit to manage a co-pilot. The co-pilot’s most recent flight before the accident was July 31, 2013 (the accident occurred October 3, 2013 (three months without flying an aircraft) and there was no evidence of a CRM training. All other NCAA recommended trainings and mandatory checks were mot performed,” the AIB concluded. The summary of the report hinged the crash to the incompetence of the pilots and the negligence on the part of the regulator, the NCAA.