Loss of Separation Incident Involving Two Jets Due to Mistaken Instruction at Portland Airport

On October 16th, 2023, an incident involving two aircraft occurred at Portland Airport due to a mistaken instruction.

An Alaska Airlines Boeing 737-800 (Registration: N508AS) performing flight AS-1299 from Santa Ana, CA to Portland, OR was on its final approach to Portland’s runway 28L. Due to adverse weather conditions, the crew opted for a go-around at a low altitude of approximately 100 feet AGL. The control tower provided instructions to the Boeing to maintain its runway heading and to ascend to an altitude of 3,000 feet, which was read back by the crew confirming receipt.

Simultaneously, a Skywest Airlines Embraer ERJ-175 (Registration: N304SY) operating on behalf of Delta Airlines and performing flight DL-3978 from Portland, OR to Seattle, WA was initiating its takeoff from Portland’s runway 28R.

After the Embraer was airborne, the control tower issued an instruction meant for it: “Skywest 3978, when able start your right turn 340”. However, this was mistakenly acknowledged by the Boeing’s crew, leading them to initiate a right turn. Recognizing the error, the control tower immediately issued corrective instructions to the Boeing: “AS-1299, fly runway heading”, soon followed by “Alaska 1298, fly heading 270”, repeated twice. Despite these clarifications, the Boeing began a leftward turn.

Realizing the potential danger, the control tower swiftly alerted the Boeing crew about the nearby Embraer. After acknowledging the traffic information, the Boeing received another set of instructions to “fly runway heading, maintain 3,000 feet”. The crew read back this directive and proceeded to align the aircraft with the extended runway centerline.

The incident concluded with the Alaska Boeing 737-800 diverting and making a safe landing in Redmond, OR, while the Skywest Airlines Embraer ERJ-175 continued its journey, landing safely in Seattle.

This incident underscores the paramount importance of clear communication and immediate responses in air traffic control, particularly in situations where multiple aircraft operate simultaneously. Subsequent investigations and preventive measures will likely be implemented to prevent similar occurrences in the future.

Sources: AirGuide Business airguide.info, bing.com, avherald.com