What happened
On 26 July, a search and rescue helicopter was conducting an operation near Ballintower, Northern Ireland. The crew was responding to a request for assistance, and the aircraft was approaching the coastline to facilitate a rescue. During the approach, the aircraft encountered a situation where the pilot was attempting to maintain position while managing visibility challenges.
While performing the approach, the aircraft experienced a sudden yaw towards the cliffs. The crew had to take immediate action to recover the aircraft and prevent it from impacting the terrain. The incident occurred during a period of low visibility, which complicated the crew's ability to maintain visual references to the coastline.
Investigation findings
The investigation revealed that the aircraft's automation, specifically the autopilot system, was involved in the sequence of events. The crew was attempting to hover or maintain a steady position near the cliffs, and a sudden change in the aircraft's heading occurred. This change was linked to the interaction between the pilot's manual inputs and the automation settings.
Crucially, the investigation found that the aircraft's heading changed because of the way the automation was configured. The crew was using a mode that was susceptible to sudden changes in heading if the aircraft's position relative to the terrain changed rapidly. The investigation also noted that the visibility conditions were challenging, which made it difficult for the crew to maintain a clear view of the coastline and the terrain.
Conclusion
The investigation concluded that the sudden change in the aircraft's heading was caused by the interaction between the pilot's manual inputs and the automation settings. The investigation also found that the visibility conditions were challenging, which made it difficult for the crew to maintain a clear view of the coastline and the terrain. The investigation recommended that the operator review its procedures for using automation in low-visibility conditions and that the manufacturer review the automation settings to ensure they are robust in challenging environments.