Although Airservices Australia used applied operational risk assessments to high-level threats, it did not formally assess and manage the risk of specific threat scenarios. As a likely result, Airservices did not formally identify and risk manage the threat of separate aircraft concurrently carrying out the MARUB SIX standard instrument departure and a missed approach from runway 34R at Sydney Airport, even though it had been a known issue among controllers generally.
The occurrence flight used a distance measuring equipment (DME) arrival to establish a visual approach in unsuitable visibility conditions. The investigation identified a number of similar approaches conducted by the operator in marginal visibility conditions.
