Japanese investigators believe a trainee pilot’s excessive nose-down input during landing caused damage to a Bombardier de Havilland Dash 8-200, but that this went undetected until a touch-and-go instruction session had ended.
The Oriental Air Bridge aircraft landed heavily on the fourth touchdown as it conducted a series of seven approaches at Nagasaki on 12 February 2014.
This approach – which included an engine-out simulation – had been carried out to runway 32, in a 17kt crosswind, by a first officer under instruction from a training captain.
Japan Transport Safety Board says the trainee probably changed from a crab approach to a wing-low attitude to counter the crosswind, and that the aircraft initially contacted the runway with its right-hand main gear.
The Dash 8 bounced and pitched up slightly, says the inquiry, and the trainee pushed on the control column – a decision which “abruptly” caused the aircraft to pitch to 4.57° nose-down.
JTSB says the trainee had thought the nose of the turboprop was “taking longer” to lower than it should have.
He had also been influenced by the captain’s observations that he tended to pitch the nose too high while switching from crabbing to a wing-low attitude, and that he also needed to push harder on the control column to maintain direction during take-off.
As a result of the nose-down input, the aircraft landed hard, with both the main landing-gear and nose-gear hitting the runway at the same time. JTSB says the recorded impact was 2.016g, and this caused the shock strut brace of the nose-gear to contact the runway surface.
Despite the pilots’ concerns about the impact, the touch-and-go exercise continued, and the Dash 8 completed three more approaches before the session ended.
Only after the aircraft was parked did an inspection reveal that it had been “substantially” damaged, says JTSB. Damage was discovered on the shock strut and tyres, and fuselage skin panels aft of the nose-gear had been deformed.
JTSB says the aircraft’s nose had been lowered “excessively” during the landing, and the instructing captain had “failed to [apply] an appropriate corrective operation”. The captain had been appointed as an instructor three months before the accident.
Source: Cirium Dashboard
