Incident Overview

Description
An Airbus A319-111 operated by Cebu Pacific sustained damage in a runway veer off accident at Manila-Ninoy Aquino International Airport in the Philippines. Flight 5J448, departed from Iloilo Airport for its scheduled flight to Ninoy Aquino International Airport with 101 persons on board. The aircraft was vectored for ILS approach to land on runway 24. At 1000 ft Radio Altitude the aircraft was stabilized and configured for landing with winds at 140 degrees/9 knots and moderate rain over the field. The aircraft was cleared to land on runway 24 with caution on a wet runway and deteriorating visibility. Before reaching 90 feet RA the wind was calm. From 80 feet RA to 35 feet RA, the wind was already at left cross to tail-cross (left rear quadrant) and at variable direction from 160 degrees – 060 degrees momentary at 013 degrees with wind speed variably increasing from 1 knot to 6 knots. At 70 feet RA, the auto pilot was disengaged and the aircraft was manually flown by the captain until touchdown. From 35 feet RA until before touchdown the wind shifted direction within the left rear quadrant and this time coming from 060 degrees to 112 degrees at increasing speed from 05 knots to 12 knots. Two seconds before touchdown the aircraft’s true heading, which was initially at 240 degrees, changed to 230 degrees with groundspeed decreasing to 119 knots, drift angle increasing from +1 degree until +9 degrees just before touchdown. The left cross-tail wind from 122 degrees to 112 degrees showed an increasing wind speed from 16 knots to 22 knots. The aircraft touched down with a heading of 230 degrees, changing further left to heading 220 degrees. Meanwhile the right hand main landing gear hit five runway edge lights with the wheels momentarily treading a portion of soft ground near the right runway edge. At the moment when the nose wheel settled on the ground and the wind speed dissipated to a low of 7 knots, the spoilers and reversers were successfully deployed and the aircraft was steered back to the runway at heading 240 degrees. Lateral control was regained by pilot. Without any ECAM fault indication, the pilot continued taxiing towards Terminal 3 for passenger disembarkation. Maintenance personnel conducted an inspection on the landing gears and discovered several cuts on both right hand tires. PROBABLE CAUSE The Aircraft Accident Investigation and Inquiry Board determined that the probable cause of this accident was: – Primary Factor: a. Inadequate Pilot skill/technique applied on unusual aircraft attitude during landing IFR with unpredicted abnormal wind shift effect. (Human Factor. Psychological. Learning. Motor conditioning) The Pilot was overconfident and dependent on the auto system of the aircraft for adjustment on shifts of wind direction and drift effect and failed to make adequate and effective corrective actions (motor skills/techniques) on the instant changes of wind direction and speed at time just before touchdown. – Contributory Factors: a. Abrupt shifts of wind direction and speed at the critical moments just before touchdown. (Environmental. Natural Environment. Wind condition) The sudden change in wind direction from the left forward quadrant to the left rear quadrant induced aircraft positive drift with late pilot response that resulted in critical skidding of the aircraft to the right with gears momentarily departing the runway pavement. The pilot was overtaken by events in making timely recognition and corrective actions to prevent entering into such dangerous situation. b. Lack of aerodrome advisory on surges of wind. (Environmental. Man-made Environment. Real time wind information) The non-availability of aerodrome information on the developing and shifting wind direction and speed that exceeded aircraft/flight limits resulted in delayed recognition and action by the pilot. – Underlying Factors: a. Inadequate Training of pilot in the probable critical scenarios at the different ladders of approach and landing. (Human Factor. Psychological. Learning. Motor conditioning) The pilot was overtaken by event during the instantly developed changes and shifts in wind condition during landing and failed to make necessary judgment or application of appropriate motor skill/technique for recovery from such unusual environmental condition. b. Inadequate aerodrome capability to provide real-time wind advisory to aircraft on landing approach. (Environmental. Man-made environment. Aerodrome Weather Radar) The aerodrome capability (radar) needs enhancement to be able to determine surges in aerodrome wind that affect landing flight path especially in the area below MDA and until touchdown and pre-warn/advise pilots on the landing approach. Adequacy of equipment such as LLWR to detect wind shear or microburst and infrastructure support can be looked into.
Primary Cause
A. Inadequate Pilot Skill/Technique ? Human Factor. Psychological. Learning. Motor conditioning: The pilot exhibited overconfidence and reliance on auto-pilot, failing to adequately adjust to the sudden and unexpected wind shift. The pilot’s response was delayed in recognizing and correcting the shift, leading to critical skidding.A. Inadequate Pilot Skill/Technique ? Human Factor. Psychological. Learning. Motor conditioning: The pilot exhibited overconfidence and reliance on auto-pilot, failing to adequately adjust to the sudden and unexpected wind shift. The pilot’s response was delayed in recognizing and correcting the shift, leading to critical skidding.Share on: