What happened
On 5 August 2017, a DHC-8-402 Dash 8, registration G-JECI, was operating a passenger flight from Inverness to Jersey. While cruising at 25,000 feet, the aircraft commander noticed the co-pilot exhibiting signs of physical distress, including muscle tension and an unresponsive state. Upon realizing the co-pilot had become incapacitated, the commander attempted to alert the cabin crew via the public address system, though the message was inadvertently sent over the intercom.
The Senior Cabin Crew Member (SCCM) responded immediately and arrived at the flight deck to find the co-er pilot experiencing a seizure. During the incident, the aircraft experienced sudden movements that caused a cabin attendant to fall. As the co-pilot underwent a second, more violent seizure, his movements caused unintended rudder pedal inputs, which resulted in the autopilot disconnecting. The commander took control of the aircraft as the pilot flying, carefully managing the controls to avoid any sudden reversals caused by the fluctuating rudder pressure.
A diversion to Manchester Airport was declared. To manage the high workload and the physical demands of restraining the co-pilot, the crew utilized an able-bodied passenger to assist the SCCM. Despite the distractions in the cockpit, the commander successfully executed a stabilized approach and landed the aircraft safely. The co-pilot was met on the ground by paramedics and transported to a hospital.
The investigation
The investigation examined flight data from the Flight Data Recorder and the Quick Access Recorder, which confirmed that the uncommanded rudder inputs were the direct cause of the autopilot's disconnection. The investigators also reviewed the operator's established procedures for pilot incapacitation. It was noted that the crew's actions—including the decision to divert, the use of passenger assistance, and the management of the flight path—were consistent with the safety protocols designed for such emergencies.
Findings
- The primary cause of the incident was the medical incapacitation of the co-pilot due to a seizure.
- The aircraft commander and cabin crew effectively managed the emergency by distributing tasks, allowing the pilot to focus on flying while the crew addressed the medical situation.
- The crew proactively addressed potential hazards, such as the risk of control reversal and the need for additional physical assistance during the landing phase.
- The co-pilot had shown no prior symptoms that would have indicated an impending medical event.