Runway separation, Boeing 737-800, VH-VXR, British Aero Plc BAe 146-300, VH-NJN

On 24 January 2006 at 0644 Western Standard Time, a Boeing Company 737-800 (737) aircraft, registered VH-VXR, was lined up on the threshold of runway 06 at Perth Airport, WA, when the aerodrome controller (ADC) issued the crew a clearance for the aircraft to take off. The crew reported that at about the same time, a British Aerospace Plc 146-300 (146) aircraft, registered VH-NJN, crossed runway 06 in the vicinity of taxiway Charlie. The 737 copilot, the non-flying pilot, advised the ADC that '…we'll just wait for the 146 crossing the runway'. The crew delayed the aircraft's take-off until the 146 had vacated and was taxiing away from the runway.

The ADC and Coordination controller considered that a runway separation standard would exist prior to the 737 commencing take-off. The 737-crew reported that they were concerned at the taxi speed of the 146 and delayed the commencement of their take-off until it had vacated the runway.

The incident highlighted the use of a Manual of Air Traffic Services (MATS) procedure for a situation for which it was not designed. The use of the adapted procedure by controllers has possibly reduced safety when used for runway crossing situations.

As an outcome from the investigation Airservices Australia has advised the Australian Transport Safety Bureau that it intends to:

• review the use of take-off/landing clearance procedures during runway crossing situations, by aircraft and vehicles
• review runway crossing procedures with a view to assessing the need for a specific runway standard for situations involving aircraft or vehicles crossing a runway during landing/take-off operations
• review the use of memory prompts or aids by tower controllers in situations involving aircraft taxiing across a runway during landing/take-off operations.