Visual Approach goes wrong Envoy Embraer lands on Wrong Runway

September 25, 2024 — Envoy Air Flight ENY3936, Embraer 170 N772MR — Chicago OHare

The Envoy crew was cleared for an ILS approach to runway 10C at Chicago O'Hare. The expected localizer information did not provide the guidance the crew expected, and the approach shifted into a visual one. The aircraft then lined up with runway 10L and landed there. The NTSB later identified runway misidentification and plan-continuation bias, while also finding that the controller did not warn the crew after seeing the wrong alignment.

The final investigation identified continuation bias and missed ATC intervention

The final investigation found that Envoy 3936 misidentified the intended runway and landed on Runway 10L instead of the cleared Runway 10C. The airplane carried 68 people and landed without injury or damage.

The approach began as an ILS procedure, but the expected localizer identification for Runway 10C was not available. The crew attempted to troubleshoot the navigation setup and then continued visually. The investigation found that continuing without the correct ILS frequency in the flight-management system contributed.

The Board also identified planned continuation bias. The crew had already committed to completing the approach and continued toward the expected runway even after the normal instrument confirmation was unavailable.

ATC was a separate part of the finding. The controller observed the aircraft aligned with the wrong runway but did not notify the crew, despite FAA directives requiring intervention in that circumstance. The final finding therefore involved both cockpit decision-making and a missed controller intervention.

The final investigation is significant because it does not stop at the wrong runway. It identifies why the crew continued after the expected ILS confirmation was unavailable and why the controller's observation did not produce an intervention. The crew's continuation bias kept the approach moving toward the expected runway, while the absence of the correct ILS frequency removed an independent navigation check. The controller then failed to warn the aircraft that it was lined up with 10L. The result was a normal-looking landing on the wrong runway with no injuries or aircraft damage.

The incident is especially useful as an investigation story because the wrong runway was not caused by a runway closure or a loss of aircraft control. The airplane was capable of making a normal landing, and the crew had an approach clearance. The failure occurred in the verification chain: the expected ILS information was unavailable, the approach continued visually, the runway was misidentified and the controller did not intervene.

“The flight crews misidentification of the intended landing runway, which resulted in an approach to and landing on the wrong runway due to their planned continuation bias.”

Accident Facts

Timeline

Sources