Findings (continued)
71. The PF made a blind Mayday call on 121.5 MHz at 15:21UTC.
72. The PF had to relay all VHF communication throughother aircraft. The radio communication relay between the PF, the relayaircraft and the ANS stations resulted in confusion communicating the natureand intent of the PF’s request for information with the required level ofurgency.
73. The PF requested from the relay aircraft immediatevectors to the nearest airport, radar guidance, speed, height and otherpositional or spatial information on numerous occasions to gauge the aircraft’sposition relative to the aerodrome and the ground due to the persistent andcontinuous smoke in the cockpit.
74. The relay aircraft did not fully comprehend orcommunicate to the BAE-C controller the specific nature of the emergency andassistance required, particularly towards the end of the event sequence.
75. There was a multi-stage process to complete astandard request for information between the accident flight and thedestination aerodrome via the relay aircraft and the ATCU.
76. The flight crew did not or could not enter thetransponder emergency code 7700, however all ATCUs were aware that the airplanewas in an emergency status.
77. DXB controllers were aware that the flight was in anemergency status, however were not aware of the specific nature of theemergency or assistance required, due to the complex nature of the relayedcommunications.
78. There was no radar data sharing from the UAE toBahrain ATC facilities. Bahrain had a direct feed that goes to the UAE butthere was no reciprocal arrangement. This lack of data resulted in the BAE-CATCO not having radar access the SSR track of the accident flight.
79. The ATC facilities are not equipped with tunabletransceivers.
80. The accident aircraft transmitted on the Guardfrequency 121.5 Mhz. The transmissions were not heard by the EACC or DXB ATCplanners due to the volume of the 121.5 Mhz frequency being in a low volumecondition.
81. The PF did not respond to any of the calls from theACC or the relay aircraft on 121.5 MHz, which were audible on the CVR, afterthe Mayday transmission.
82. During the periods when direct radio communicationsbetween the pilot flying and the controllers was established, there was nonegative effect. Therefore it is likely that if direct 121.5 contact had beenestablished the communications task could have been simplified.
83. The relay aircraft hand off between successiveaircraft caused increasing levels of frustration and confusion to the PF.
84. All Dubai aerodrome approach aids and lightingfacilities were operating normally at the time of the accident.
85. There is no requirement for full immersion smoke,fire, and fumes cockpit training for flight crews.
86. The PF selected the landing gear handle down. Thelanding gear did not extend, likely due to loss of cable tension.
87. The flaps extended to 20°. This limited the autothrottle power demand based on the max flap extension placard speed at 20°Flaps.
88. The PF was in radio contact with a relay aircraft,who advised the PF through BAE-C that Sharjah airport was available, and a lefthand turn onto a heading of 095° was required.
89. The PF made an input of 195° into the MCP for anundetermined reason when 095° was provided. The aircraft overbanked to theright, generating a series of audible alerts. It is probable that the PF, inthe absence of peripheral visual clues, likely became spatially disorientatedby this abrupt maneuver.
90. The aircraft acquired 195°, the AP was selected off.The throttle was retarded and the aircraft began a rapid descent.
91. The PF was unaware of the large urban area directlyin the airplane’s path. The aircraft began a descent without a defined landingarea ahead.
92. Spatial disorientation, vestibular/somatogyralillusion due to unreliable or unavailable instruments or external visualreferences are a possibility. The PF was unaware of the aircraft locationspatially. The PF may have been attempting an off airfield landing, evidencedby numerous control column inputs.
93. The control column inputs to the elevators had alimited effect on the descent profile. The pilot made a series of rapid columninputs, in response to GPWS warnings concerning the sink rate and terrain. Theinputs resulted in pitch oscillations where the elevator response decreasedrapidly at the end of the flight
94. The available manual control of pitch attitude was minimal,the control column was fully aft when the data ends, there was insufficienttrailing edge up [nose up] elevator to arrest the nose down pitch. Control ofthe aircraft was lost in flight followed by an uncontrolled descent intoterrain.
95. The aircraft was not equipped with an alternativeviewing system to allow the pilot(s) to view the instruments and panels in thesmoke filled environment.