In September 2017, an Emirates A380 carrying 448 passengers and crew was descending through the nighttime darkness to land at Moscow’s Domodedovo Airport. Nothing unusual about that. What gave this flight a certain edge was that it was just 504ft above the ground and descending at 1,600 feet per minute. It was also over seven nautical miles out of Domodedovo.
Airbus A380 gets as low as 395 feet above the ground
In what the UAE’s General Civil Aviation Authority (GCAA) is classifying as a serious incident, A6-EEZ was operating EK131 from Dubai to Moscow on 10 September 2017. According to the GCAA’s final report into the incident, the aircraft got as low as 395 feet above the ground before the ground-proximity warning system activated, and the crew pulled the plane up.
The report states that A6-EEZ was on a runway 14R ILS approach while on the base leg. Before establishing on the localizer, the plane descended below its cleared altitude of 500 meters QFE. The aircraft was alerted to stop the approach and perform a go-around. It was at this time that the plane was just 395 feet about the ground, and the alerts were activated.
On the second landing attempt, A6-EEZ dropped off the flight management system screens. The Captain selected the UUDD14R waypoint with the direct-to function in the flight management system. This caused the plane to level off at 2,600 feet QNH, and another go-around was performed. The aircraft landed on the third attempt without injury to passengers or crew.
It was found that in the first approach, there was poor communication between the flight crew and that they erred by believing that the plane would capture the three-degree glideslope from above. Having carried out the glide interception from above procedure, one of the pilots focused on the horizontal position of the aircraft to establish on the localizer. Neither pilot had a correct awareness of the aircraft’s vertical position. Consequently, A6-EEZ was descending below its cleared altitude.
On the second approach, the investigation found other issues. There was no flight plan on the navigation display. After the first go-around, the flight management system was not reconfigured by re-sequencing the flight plan as per standard operating procedures. There was also aircraft oscillation around the localizer course. This caused the pilots to select the waypoint using the DIR TO function.
The investigation notes several contributing factors
The GCAA’s investigation found the following issues were contributing factors. The first was the co-pilot’s belief that radar control might not provide them with vectors to intercept the localizer at an angle of 45 degrees or less when the plane was on its base leg. Second, the glide interception from above procedure was underway before the aircraft had established on the ILS localizer for runway 14R.
Third, between performing the glide interception from above procedure and the go-around, the plane’s position was initially outside the azimuthal coverage of the ILS glideslope signal. When the aircraft was within coverage, it was outside the elevation coverage of the glideslope signal. As a result, the displayed glideslope deviation indications were incorrect.
Fourth, before performing the first glide slope interception from above procedure, the crew’s false representation of the aircraft’s position led them to believe that they were being vectored to a tight approach and that the plane would capture the glideslope from above.
As a result, the pilot referred only to the glideslope deviation indication to establish the aircraft’s vertical position rather than considering other indicators such as pressure altitude, vertical, and navigation displays. It also caused the pilot to drop below the cleared height and to modify the ATC vector headings.
Fourth, there was some criticism of the radar controller’s language as non-standard considering the urgency of the situation.
On the second approach, a real-time computer issue caused an automatic reset of FMS1. When that was complete, the pilots did not reconfigure the flight management system by inputting the runway 14R ILS approach. The pilots did not believe their doing so would jeopardize the capture of the localizer by the automatic flight system.
The Emirates response to the incident
As a result of the incident, Emirates has taken the following steps.
First, they have reviewed the procedure to intercept the glideslope from above and current differences between fleets. Emirates is harmonizing the procedure and aligning it with the best industry practice.
Second, a new flight safety update was published in 2018. This update makes crew aware of the problems of using ILS outside the certified envelope.
Finally, additional and recurrent training is now provided to crews to highlight awareness of the issue.