decision altitude การใช้

• This call was made about 100 ft below the " decision altitude ".
• While on approach to Sofia Airport in heavy snow, the crew failed to make visual contact with the ground as they descended below decision altitude.
• Due to increased azimuth error associated with the use of VORs and lack of vertical guidance ( Glide Slope ), the MDA is therefore much higher than a DA ( Decision Altitude ) for an ILS.
• Apparently, the pilots had difficulty in sighting the runway and should have carried a missed approach on the Decision Altitude of 307 ft instead of continuing descent below 204 ft . The flaps were retracted and the gear was extended.
• ICAO defines decision altitude / decision height as a specified altitude or height ( A / H ) in the precision approach at which a missed approach must be initiated if the required visual reference to continue the approach has not been established.
• Embraer offers an enhanced flight vision system constituted by the Rockwell Collins HGS-3500 Head-up display combined with the EVS-3000 Infrared camera, permitting a decision altitude necessitating visual references of 100 ft above touchdown at a projected price of $ 515, 000.
• A DH / DA denotes the altitude in which a missed approach procedure must be started, it does not preclude the aircraft from dipping below the prescribed DH / DA . A decision height is measured AGL ( above ground level ) while a decision altitude is measured above MSL ( mean sea level ).
• From the FDR data, it was revealed that the flight was uneventful until its final approach . 30 seconds before the crash, the aircraft descended for 7 seconds and leveled off at an altitude of 204 ft, which is below the Decision Altitude of 307 ft . The airspeed then decreased to 145 knots.
• A decision height ( DH ) or decision altitude ( DA ) is a specified lowest height or altitude in the approach descent at which, if the required visual reference to continue the approach ( such as the runway markings or runway environment ) is not visible to the pilot, the pilot must initiate a missed approach.
• Further study by the Interstate Aviation Committee regarding the cockpits voice recordings revealed that there was never a direct command for the pilot to go through with the landing, but the report did show that the pilot was under a " cascade of stress much of it emanating from his powerful passengers, as Captain Protasiuk slipped below the decision altitude ".
• The final report stated that the accident resulted from the pilots lack of a common action plan during the approach, the final approach being continued below the Minimum Decision Altitude without ground visual reference being acquired, the inappropriate application of flight control inputs during the go-around and after the activation of the Terrain Awareness and Warning System, and the flight crew s lack of monitoring and controlling of the flight path.
• The controller remained silent for about 12 seconds after the aircraft passed the 100 m mark, and, even at that point, he did not order a go-around, but, rather issued an instruction to transit from a descent to a horizontal flight . ( The decision to go around was apparently reached in the cabin of the aircraft within a few seconds of that instruction . ) In addition, according to some interpretations of the radio exchange between the ground and the aircraft, the crew was instructed by the ground control to descend to and either to wait for clearance to land or request one explicitly, or to inform the ground control regarding their decision whether to land or to go around . ( According to MAK's report, it meant that the crew was supposed to inform the ground control of their decision to land before passing the decision altitude, and that the ground control was supposed to allow the landing as long as the runway and the airspace were clear . ) None of this ever happened, with the aircraft continuing the descent through the 120 m mark while the ground control remained silent.