On 23 October 2020, a Bombardier DHC8-400 (JA845A) being operated by Oriental Air Bridge for All Nippon Airways on a scheduled domestic passenger flight from Fukuoka to Fukue as OC93 touched down at destination in day VMC with an excessive pitch attitude and the resulting runway contact caused substantial structural damage to the airframe but none of the 54 occupants were injured.
The accident aircraft - the tailstrike damage was just aft of the rear door. [Reproduced from the Official Report]
After prompt notification, the Japan Transport Safety Board (JTSB) began an Accident Investigation the following day. Recorded data from the FDR and CVR were downloaded and included useful information. Relevant data were available from the QAR. Relevant meteorological data and recorded R/T communications between the flight and the Remote Tower location were also available.
It was noted that the 67 year-old Captain, who was acting as PF for the accident flight, had a total of 18,157 hours flying experience including 947 hours on type. The 31 year-old First Officer had a total of 3,587 hours flying experience including 1,866 hours on type.
What happened and why
It was established that the visual approach to runway 03 had been conducted in somewhat turbulent conditions in accordance with applicable SOPs including those relating to Route Manual weather-related restrictions for flight into Fukue, the general requirement for a stabilised approach to be flown with cautionary speed variation calls from the PM First Officer and specifications related to the handling pilot’s aircraft type experience.
The AP was disconnected as the aircraft passed about 700 feet agl. However, FDR data showed that once the aircraft was over the runway and the flare had been commenced (at a suitably low height for the circumstances of 20 feet agl), the instantaneous headwind component had reduced. This required an appropriate flight path control response to compensate for reduced aircraft forward speed and increased rate of descent but instead of responding primarily by adding power, the Captain began to increase pitch attitude. When he continued to do so as pitch increased above the 6° threshold notified in the AOM as likely to result in a tailstrike, this became inevitable. When the tail initially struck the ground at a point 152 metres from the beginning of the runway, a corresponding warning was annunciated on the flight deck and the Captain’s subsequent visual inspection confirmed this. FDR data showed that the aircraft pitch attitude had reached a maximum of 9° during runway contact.
An engineer’s inspection of the damage subsequently confirmed that skin abrasion (including cracks) was present on the lower fuselage over an area approximately 2.1 metres long and up to 0.6 metres wide with the associated internal structure “damaged and deformed”.
An annotated ground track of the investigated approach. [Reproduced from the Official Report]
The Probable Cause of the Accident was recorded as the excessive nose-up attitude of the aircraft causing the lower side of its tail to contact the runway because the Captain continued the nose-up operation until moments before the touchdown when the aircraft did not stop descending due to the airspeed reduction caused by turbulence during the landing flare.
Safety Action taken by Oriental Air Bridge as a result of the Accident and known to the Investigation was noted as having included but not been limited to the following actions:
- in order to maximise monitoring and assertion by the PM, procedures have been revised to require that the PM should call ‘PITCH’ if the pitch angle exceeds 5° after passing the runway threshold.
- meteorological characteristics at remote island airports (such as Fukue) have been documented for operational awareness.
- pilots with little experience of operations at remote island airports served by the operator have been made aware of relevant meteorological characteristics of each such destination.
The Final Report was adopted by the JTSB on 5 August 2022 and published on 25 August 2022. No Safety Recommendations were made.