What happened
On July 27, 2018, a high-risk situation developed at Amsterdam Airport Schiphol involving an Embraer ERJ 190-100 STD, registered PH-EXV, and a Boeing 737-800, registered PH-BXI. The Embraer was stationary at the start of runway 18C when it was granted take-off clearance. Simultaneously, the Boeing 737 was cleared to line up for an intersection take-off using high-speed exit W4 on the same runway.
As the Embraer began its take-off roll, the crew of the Boeing 737 stopped past the hold short line and notified air traffic control that they were positioned on the runway. Upon hearing this, the runway controller issued a take-off clearance to the Boeing 737. The Embraer crew noticed the Boeing 737 and aborted their take-off. The Runway Incursion Alerting System (RIASS) triggered an alarm only after the Embraer had already begun to decelerate. The two aircraft eventually passed each other, with the Embraer passing the stationary Boeing 737 at approximately 85 knots, maintaining a separation of roughly 19 meters.
The investigation
The investigation examined the operational complexities at Schiphol, specifically the use of intersection starts and the workload of the runway controller. The investigation noted that the controller was managing multiple active runways (18C, 09, and 22) and was dealing with increased complexity due to non-standard runway features. Furthermore, the controller had been involved in two other air traffic incidents earlier in the same shift, which may have impacted mental resilience.
Findings
- The primary cause of the potential collision was the simultaneous issuance of take-off clearances for two aircraft on the same runway section.
- The use of intersection starts via high-speed exits increased the risk, as it makes it difficult for crews to see approaching traffic from the runway start.
- The Runway Incursion Alerting System (RISS) failed to act as an effective early warning, as the alarm sounded only after the Embraer had already initiated its abort sequence.
- Increased controller workload and the complexity of managing multiple runways and non-standard procedures contributed to the error.
- The controller's decision to allow an intersection start, rather than instructing the Boeing 737 to line up behind the Embraer, increased the operational risk.