Description

On 20 February 2018, a Boeing MD-83 (5N-SRI) being operated by Dana Airlines on a scheduled domestic passenger flight from Abuja to Port Harcourt as DAN36A3 veered off the side of the landing runway after touching down at night in reduced runway visibility during heavy rain and ended up 300 metres beyond the end of the runway. None of the 49 occupants were injured in the accident or the subsequent emergency evacuation but damage to the aircraft was substantial and there was impact damage to ground lighting and navigation aids.

The AFRS arrived whilst the evacuation was taking place and it was completed without any injuries. As well as “substantial” damage to the aircraft, some runway 03 approach lights were broken as was the ILS LOC antenna and the “ILS light stand”.

Relevant Circumstances Other than Flight Crew Performance

A calculation of the landing performance for the accident flight with the aircraft as configured was made and it confirmed that made by the crew. It showed that even in the environmental conditions which had been present (including a 19 knot tail wind component) and assuming a runway with at least the minimum required surface friction, if the aircraft had crossed the threshold at 50 feet agl and then touched down firmly in the TDZ, that it should have come to a stop 2,070 metres past the threshold leaving 930 metres of runway ahead of the aircraft.

The pilots stated that “the runway had experienced recent rain before arrival, and after touchdown looked and felt contaminated with flood of water that did not drain well”. In the usual absence of any hard evidence as to what the water depth might actually have been, the possible effect of the condition of the runway surface was examined and it was noted that although the responsible authority, the Federal Airport Authority of Nigeria (FAAN), claimed that necessary monitoring and maintenance had been taking place, they had not provided any detail on this and stated only that it was “supervised by the airport authorities and conducted by field engineers and other airfield operations personnel”.

The Investigation found that runway friction testing at Port Harcourt was carried out by a contractor and noted that a 2018 CAA Audit of the airport had recorded that “the FAAN claimed to have conducted the last friction test on runways 03/21 in 2012” but did not provide any documentary evidence to support this claim. It was found that “there was no record of any corrective maintenance action on the runway” prior to the accident although the most recent validation of the extent of rubber deposits on runways 03/21 as “satisfactory” had been made in December 2017.

During their initial inspection of the flight deck, the Investigation Team discovered that two overhead panel CBs were tripped, those protecting the anti skid test and COM 2 which was taken to indicate that both were therefore likely to have been inoperative during the landing. The tripped COM 2 CB would have explained the First Officer’s inability to communicate with TWR but no evidence was found as to why it had tripped. The absence of anti skid on a rain-soaked runway was likely to have contributed to the difficulty of stopping the aircraft on what remained of the runway after touchdown and it was surmised that since the anti skid self-test operates automatically when the main landing gear extends, this is when it had most likely occurred.

The loss of directional control near to the end of the runway was noted as having been potentially a consequence of viscous aquaplaning which “often occurs […] where rubber deposits are present, usually in the touchdown area where (even) a thin water film can significantly reduce the coefficient of friction”. In such circumstances, it was observed that “the effects of even minor differential manual braking are likely to be greater” and that any reduction in nose landing gear wheel adhesion “directly limits both steering input options and the usual directionally-stabilising effect of the nose landing gear”. It was also noted that “transverse scuff marks found on some of the tyres also indicated that they had been subjected to a skid” and that the offset between these marks on the nose gear and main gear confirmed the aircraft had been in a slight yaw to the left as it left the runway centreline.

Flight Crew Performance

Relevant guidance on approach and landing in the MD80 FCOM and the Dana Airlines OM Part ‘B’ was reviewed and it was concluded that the conduct of the final stages of the approach and the landing in the observable conditions had been contrary to a range of applicable SOPs. It was also noted that and the accident had occurred in the presence of ineffective CRM in a situation where the Captain had been overloaded and the very inexperienced First Officer was a less effective PM than greater experience might have facilitated. However, it was also observed that “in the absence of information and training about un-grooved and wet/contaminated runways, there is a risk that the flight crew will not carry out the appropriate landing techniques under these conditions”.

Overall, it was considered likely that the flight crew had not considered that the situation warranted a go around, had “believed that the entire approach was stabilised” and with the runway in sight had simply “disregarded the presence of high winds and the other deteriorating metrological conditions”.

The Investigation took the view that on encountering a situation which required the flight crew to “adapt to rapidly changing weather conditions”, a series of active and latent failures related to flight management which had been “multiple and interactive” could be identified.

Active failures identified included the following:

• Underestimation of weather conditions due to lack of information from ATC.
• Wrong pairing of crew using a First Officer who was yet to be released to operate unsupervised on a Public Transport flight with a Line Captain.
• The Captain was overwhelmed by open discussions with the First Officer relating to the flight, approach and landing procedures.
• Non-adherence to company SOP.
• Non-implementation of proper cockpit resource management (CRM) procedures.

Latent failures were identified as including:

• Inadequate risk management strategy by the flight crew as a result of deficient airline procedures and training for landings under wet/contaminated runway conditions.
• Deficiencies in airline organisational processes regarding effective and efficient monitoring of the implementation of appropriate procedures.

The Cause of the Accident was determined as “an underestimation of the degradation of weather conditions (heavy rain, visibility and strong wind on short final and landing) and the failure by the crew to initiate a missed approach which was not consistent with the company’s SOP”.

Three Contributory Factors were also identified as follows:

• Non-compliance to SOP in meeting crew competency and complement.
• Ineffective two-way communication between the ATC and DAN363 during final approach prevented the flow of technical information on runway surface condition and other relevant meteorological information essential to safety.
• Failure of the crew to crosscheck the prevailing wind and also to obtain landing clearance from the ATC during final approach after contact with ATC was restored.

Nine Safety Recommendations were made as a result of the Investigation as follows:

• that Dana Airlines should review the guidelines for developing, implementing, reinforcing, and assessing CRM training programmes for both flight and cabin crew members as contained in the DANA Airline Operations Manual Part D (Training) sections 2.9.5 - 2.9.5.5 and ensure that the CRM programme conforms to the provisions contained in the Nigerian CARs at Part 8.10.1.12. [2019-011]
• that Dana Airlines:
  1. Amend its Operations Manual Part D section 2 “Flight Crew Training and Checking Programme”, subparagraph 2.5.2.4 Line Training Under Supervision, to state that:
     • All flight crew members will operate a minimum number of sectors and/or flying hours, whichever comes later, under the supervision of a nominated Check Pilot shall be part of the operating crew and be in command..
     • The normal minima for Line Flying under supervision (in addition to any base training) will be:
       • Captains and First Officers on type 50 hours (minimum 20 sectors).
       • Captains and First Officers non-reducible transiting to a new aircraft type 100 hours (minimum 30 sectors).
  2. For pilots with more than 500 hours on type and recent experience of an equivalent jet in the area of operations, the above criteria may, at the Flight Training Manager’s discretion, be reduced by up to 40%.
  3. A risk identification, assessment and reduction processes should be conducted in a structured proactive and systematic way so that it cuts across all relevant personnel, rather than relying on the crew decision-making abilities when it comes to complying with SOP. [2019-012]
• that the Federal Airports Authority of Nigeria (FAAN) should conduct Friction Tests and de-rubberisation of all active runways under their control in compliance with Part 12.6.4(d) of the Nigerian CARs 2007 in accordance with NCAA advisory circular NCAA-AC-ARD014 issue No.1. [2019-013]
• that the Federal Airports Authority of Nigeria (FAAN) should monitor surface friction test schedules on all operational runways on a more frequent basis, including the build-up of rubber on all runways, and perform rubber removal operations as required, in accordance with Part 12.6.4(d) of the Nigerian CARs 2007. [2019-014]
• that the Federal Airports Authority of Nigeria (FAAN) should ensure that a comprehensive maintenance plan for runways in all airports under its control is developed and ensure that there is effective record keeping for every detail of maintenance carried out. [2019-015]
• that the Nigerian Airspace Management Agency (NAMA) should amend the Manual of Air Traffic Control (MAT-C) Vol. 1, 2nd edition Chapter 4, “Windshear” Section 1, sub section 1.5 to include “Low Level Windshear Advisory,” to state that Tower controllers should issue the LLWAS advisory “Low Level Windshear Advisories in Effect” whether or not the facility is equipped with an ATIS. The advisory should continue to be transmitted by ATC, relative to all runways in operation at the airport, until either the information is confirmed to be on the ATIS, or the prescribed 10-minute time limit from the time the alert was issued has been reached. [2019-016]
• that the Nigerian Airspace Management Agency (NAMA) should ensure that the Manual of Air Traffic Control (MAT-C), Chapter 4, “Windshear” Section 1, sub section 1.5 is appropriately revised to include “Low Level Windshear Advisory” to require controllers to select for display all sensors on the LLWAS (if installed at the airport) when adverse weather conditions, such as thunderstorms, are forecast or present in the terminal area to improve controller and pilot perception of wind conditions affecting the entire airport. [2019-017]
• that the Nigerian Civil Aviation Authority (NCAA) should review the pilot training record keeping systems of DANA Airlines to determine the quality of information contained therein and require the airline to maintain appropriate information on the quality of pilot performance in training and checking. [2019-018]
• that the Nigerian Civil Aviation Authority (NCAA) should ensure that all airport operators in Nigeria conduct Runway Friction Tests regularly in accordance with Nigerian CARs Part 12. [2019-019]

The Final Report of the Investigation was published on 25 April 2019.

Related Articles

• Runway Excursion
• Landing on Contaminated Runways
• Runway Surface Friction
• Aquaplaning
• Low Level Wind Shear
• Wind
• Touchdown Zone (TDZ)
• Cumulonimbus (Cb)
• Runway Surface Condition Reporting
• Crew Resource Management (CRM)
• Continuation Bias
• Authority Gradients
• Missed Approach
• Standard Operating Procedures (SOPs)