Case Studies
Augmenting & Reinforcing Incident Data
NOSS findings
For several months, there were dramatic spikes and decreases in incidents pertaining to discrepancies of cleared altitudes and what was expected / coordinated with the next sector. The factors behind these incidents, and the reasons why they ebbed and flowed over a several month period was not understood. The NOSS data also detected differences in this group of sectors relative to other sectors at
the facility. Specifically, there was a tendency amongst some controllers to “pre-load” the data block – changes were made to the altitude in the data block prior to instructions being issued to aircraft. This appeared to be the underlying behavioral practice that was leading to the incidents (and believed to be an adaptation to the high number of interactions required with the automated system).
Response to findings
Educational efforts were made to underscore the importance of coupling the act of issuing the altitude instruction (and receiving a correct readback) and making changes to the data block. These efforts were backed up by the supervisors and auditing regime
