Aircrew Captain not only clearly violated the prescribed procedures for circling approach, but also did not at all adhere to FCOM procedures of displaying reaction / response to timely and continuous terrain and pull up warnings (21 times in 70 seconds) - despite these very loud, continuous and executive commands, the Captain failed to register the urgency of the situation and did not respond in kind (break off / pull off).
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The captain (61, ATPL, 25,497 hours total, 1,060 hours on type) was pilot flying, the first officer (34, CPL, 1,837 hours total, 286 hours on type) was pilot monitoring.
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5nm north of the aerodrome a first EGPWS caution "TERRAIN AHEAD" sounded. The first officer told the captain "this Sir higher ground has reached, Sir there is a terrain ahead, Sir turn left.
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The investigation commission commented at that point: "By now the Captain had become very jittery in his verbal communication and displayed frustration, confusion and anxiety resulting in further deterioration in his behaviour."
Tower inquired whether they were visual with the airfield, no reply from the captain, the first officer queried "what should I tell him?"
The tower controller queried whether they were visual with the ground. Both captain and first officer responded confirming they were visual with the ground. The first officer again pointed out: "Sir terrain ahead is coming", the captain responded "we are turning left". The heading bug was rotated left, however, the aircraft did NOT turn. Two "TERRAIN AHEAD" aural caution messages sounded.
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From that point multiple "TERRAIN AHEAD PULL UP" EGPWS alerts sounded until impact.
The first officer begged twice in succession "Sir, turn left, pull up Sir! Sir, pull up!"
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The first officer begged another time "Sir, pull up, Sir!"
6 seconds prior to impact the first officer exclaimed "TERRAIN, SIR"... 3 seconds prior to impact the EGPWS alerted "PULL UP", the first officer exclaimed "Sir, we are going down! Sir, we are going down!"