By Simon Hradecky, created Saturday, Feb 4th 2012 21:41Z, last updated Saturday, Feb 4th 2012 21:41Z Japan's Transportation Safety Board (JTSB) released their final report in Japanese concluding:



During the descent to the destination airport Asahikawa under guidance by air traffic control the aircraft descended towards terrain until the EGPWS sounded an alert that prompted the crew to respond according to required procedures and initiate the correct evasive maneouver. The aircraft had been vectored below minimum vectoring altitude (MVA) because the air traffic controller had forgotten to check the MVA before providing vectors that took the aircraft into the mountaineous region east of the aerodrome. The check was forgotten because air traffic control was working a number of other aircraft in frequent transmissions and lost awareness. The crew did not cross check and challenge the descent instruction by the controller. The crew thought MVA had been applied by the controller. Although the first officer used the navigation display with its vertical situation display (VSD) showing the mountaineous terrain and recognized the approach to danger, he did not advise the captain.



The controller was working high and low center controlling aircraft up to FL400 as well as approach to Asahikawa. A second aircraft was on approach to Asahikawa as well and requested to abort the approach because of some minor trouble, another aircraft requested higher due to turbulence. The controller changed the approach sequence and instructed the aircraft aborting the approach to enter the holding at Asahikawa VOR at 8000 feet and acknowledged the request for higher by "Standby". The controller subsequently advised NH-325 of now being number one for the approach, instructed the aircraft to turn onto a heading of 090 degrees for being vectored onto the ILS approach, then instructed the aircraft to descend to 5000 feet (MVA 10,000 feet, MSA 9,600 feet). About one minute after the instruction to descent the crew requested to turn right towards Asahikawa VOR and were cleared to turn onto a heading of 200 degrees, 43 seconds later "resume own navigation direct Asahikawa VOR". 7 seconds after that instruction the EGPWS issued a terrain alert, audible on the ATC frequency as the crew was just about to call ATC, the controller repeated "resume own navigation direct Asahikawa VOR". The crew reported they had a terrain alert and were climbing to 10,000 feet, then indicated they were evading terrain. The controller acknowledged instructing the aircraft to maintain 10,000 feet at a heading of 200 degrees.



After the crew reported clear of terrain the crew, now in Japanese after all ATC communication had been done in English so far, requested to turn towards Asahikawa VOR and to be cleared for the approach.



The controller instructed the aircraft again to descend to 5000 feet, after readback however changed to descend to 7000 feet (still below MVA of 9000 feet MSL for that sector), and turn to Asahikawa VOR to enter the holding pattern at the VOR, advising NH-325 that another aircraft was holding at Asahikawa VOR at 8000 feet.



The captain (34, ATPL, 4,058 hours total, 1,225 hours on type) had been promoted to be captain three months prior to the incident and was still under supervision. He was pilot flying. The right hand seat was occupied by a training captain (48, ATPL, 14,484 hours total, 10,776 hours on type) assuming the role of the first officer and pilot monitoring. Instrument Meteorologic Conditions prevailed during the approach.



On approach the crew had been cleared to descend to 9000 feet and subsequently turn onto a heading of 090 degrees. The aircraft was subsequently cleared to descend to 5000 feet and turn onto a heading of 200 degrees. While turning onto 200 degrees and descending through 7200 feet MSL the EGPWS issued a terrain caution. The first officer changed his ND to a range of 20nm about 5 seconds later. 10 seconds after the terrain caution the EGPWS issued a terrain warning together with "Pull Up!", radio altitude (height above terrain) at that point was 3200 feet. The autopilot was turned off, nose up inputs were provided by the crew and the wings were rolled level. The autothrottle was disengaged and the thrust levers pushed forward. The aircraft began to climb 3 seconds after the first "Pull Up" aural alert, the pull up alerts ceased 15 seconds after the terrain warning, radio altitude was 2200 feet at that point, the pitch angle that had reached 18 degrees nose up started to reduce. 9 seconds after the Pull Ups had ceased the aircraft rolled right to continue the turn, the throttle levers were moved backwards to reduce thrust according to the reducing rate of climb.



16 seconds after the pull ups had ceased the EGPWS, now sensing the conflict with the Pippudake peak, 2197 meters/7208 feet of height, issued another terrain warning immediately followed by another nose up inputs and the thrust levers being pushed forward. The aircraft increased its climb and the Pull Ups ceased 5 seconds later after the aircraft had overflown the peak with a radar altitude of 713 feet. The crew continued the climb to 10,500 feet, above the minimum vectoring altitude of 9500 feet.



The training captain serving as first officer stated in interviews that when they were descending through 8500 feet in cloud, he thought by himself any lower than that would be dangerous already while watching his ND/VSD. The captain then requested to turn directly to Asahikawa and they were instructed to turn onto heading 200, almost immediately followed by the EGPWS caution and warnings.



The air traffic controller said, that he could not vector NH-325 to proceed directly to Asahikawa VOR as a vertical separation was not possible with the aircraft entering the holding at 8000 feet. He therefore decided to use lateral separation of 10nm taking NH-325 to the east, but forgot to check for the minimum vectoring altitude before providing such vectors.



The JTSB seriously criticised the cooperation between the two crew members as well as communication of the first officer with ATC in their analysis. The JTSB stressed that the principle of crew resource management require each crew member to voice any thoughts concerning the safe conduct of the flight as well as the crew to cross check ATC instructions. Although following ATC instructions is main principle the crew should have checked the instructions and queried any instruction that would be in conflict with the safe conduct of the flight. The first officer/training captain, responsible for communication with ATC and assuming the role of the pilot monitoring, should have recognized the instruction to descend below minimum safe altitude (MSA) and thus should have queried the controller's instruction. He later should have immediately voiced his concern when he thought by himself in view of the vertical situation display that a further descent was unsafe.



The first officer's navigation display including vertical situation display before the conflict (Photo: JTSB):





The captain's navigation display upon terrain alert (Photo: JTSB):





The controller's two screens, left radar, right flight strips (Photo: JTSB):





The critical flight trajectory (Photo: JTSB):





The conflicting flight trajectory (Photo: JTSB):



