A Thai Airways Airbus A350 was involved in a serious landing incident, on January 1st 2020; which involved the aircraft descending below 670 feet, whilst still nearly 6.5 nautical miles from the airport.
The aircraft, an Airbus A350-900 registered HS-THF, was performing flight TG-926 from Phuket when the incident occurred. Although at night, conditions and visibility were good.
During descent, the pilots increased their descent rate while passing through 7,300 feet; as instructed to do so by air traffic control. Not long after clearance was provided to descent to 3,000 feet, at a heading of 040 degrees with a speed of 170 knots or higher. The aircraft was set up and cleared for an ILS approach into Frankfurt.
At 6,000 feet the flaps were extended, with the landing gear being deployed at around 5,100 feet. By this time the descent rate was 2,000 feet per minute, just as the aircraft intercepted the localiser to begin its final approach sequence.
With the ground proximity warning system (GPWS) calling out 2,500 feet, the autopilot system was disconnected. However, approximately nine seconds later another two GPWS call outs were made, this time alerting the crew of the sinkrate before calling out 1,000 feet.
Noticing the issue, the pilot monitoring notified Frankfurt air traffic control; which was the first actual contact with the tower during approach. At this point the German Federal Bureau of Aircraft Accident Investigation states that the aircraft was at an altitude of 668 feet above ground level, 6.5 nautical miles from the airport runway.
A go around was performed, with the aircraft climbing out of the near-disastrous situation without further incident. During the second approach the correct altitude for the distance to the airport was achieved, being approximately 2,100 feet.
To compare the approaches another illustration was published for the investigation, highlighting the serious vertical flight path deviation.
On board the flight were three first officers and a captain. The German Federal Bureau of Aircraft Accident Investigation says that the first officer, that was flying the aircraft at the time, was 36 years old, held an airline transport pilot license (ATPL) and had a total of 4,000 hours of flying experience; with 1,500 of these hours being on the A350.
The 43 year old captain monitoring the first officer holds 8,000 flying experience, with 400 hours on the A350. The two other first officers that were on board at the time were not in command positions. Each had their ATPL and were not undergoing training.
Due the seriousness of the incident, the German Federal Bureau of Aircraft Accident Investigation has launched an in-depth investigation; this will likely focus on pilot awareness and fatigue, pilot mental state and how information is viewed during such a critical stage of flight.
It is also understood that the pilots are being investigated by Thai authorities, for a serious breach of procedure that put a large aircraft and the lives of passengers, crew and those on the ground at risk.