German Investigators Release Final Report for SQ 77W Runway Excursion
On the 17th of December, the Bundesstelle fur Flugunfallunstersuchung released the final report into 9V-SWQ runway excursion in November 2011. The crew was using the Autoland system for the landing, even though the ground conditions were not safe to conduct the landing.
The aircraft uses a signal called the Localiser to know how to fly the approach. However, the signal was interrupted by a departing BAE146, resulting in a left deviation.
Upon landing, the autopilot remained on meaning that the pilots could not perform a go-around. The autopilot also steers the aircraft on the ground, trying to keep it on centreline. The autopilot was only disengaged after rudder inputs from the pilots. The pilots were able to recover the aircraft and bring it to a stop parallel to the runway.
There was no damage to the aircraft and no passengers or crew were seriously injured upon landing. The aircraft was disembarked via side stairs.
Cause of the incident:
According to the BFU, the immediate causes of the incident were:
- Autoland landing in conditions on the ground not safe.
- Shortly before landing, the LOC signal was interupted by a departing BAE 146.
- Pilots unable to control plane upon landing as the autopilot was still on ‘Roll-Out’ mode.
- The crew were unable to perform a go-around as this mode was disabled when the left main gear touched the ground.
Systemic causes were:
- The flight crew operation manual (FCOM) from Singapore Airlines allowed for an autoland landing without considering the weather conditions on the ground.
The BFU recommended that Singapore Airlines add additional guidelines for flight crews during training in regards to go-around procedures after the aircraft enters ground mode.