What happened
During a busy period involving an instrument landing system (ILS) approach sequence, a significant loss of separation occurred among the participating aircraft. The incident involved eight out of the nine airplanes in the approach chain. These separation breaches were not confined to a specific geographic segment; they manifested both inside and outside the outer marker zone along the final approach path.
The investigation
Air traffic control records indicated that the local controller was aware of the situation prior to assuming full responsibility for the sequence. Specifically, the controller had been informed by TRACON (Terminal Radar Approach Control) that the separation between the aircraft was "tight" during the handoff process. Despite this awareness, the spacing issues persisted.
Upon recognizing the critical nature of the situation, the local controller attempted to implement remedial actions. These measures included notifying a supervisor about the tight spacing and issuing missed approach instructions to two of the involved airplanes to break up the formation and restore safe separation standards.