Philip Argy
12th February 2009, 07:28 PM
The ATSB has today issued its final report on the May 2007 separation breakdown between a B767-300 inbound to 34L and a SAAB 340B outbound off the same runway.
Here is the abstract:
On 8 May 2007 at about 1858 Eastern Standard Time, a Boeing Aircraft Company 767-338 (767), registered VH-OGI, was inbound to Sydney, NSW from Melbourne, Vic. on descent to 6,000 ft and a SAAB Aircraft Company 340B (SAAB), registered VH-OLL, was departing Sydney for Moruya, NSW on climb to FL140. The distance between the aircraft reduced to 1.5 NM horizontal and 400 ft vertical separation. Separation standards as specified in the Manual of Air Traffic Services (MATS) required the provision of either 3 NM horizontal or 1,000 ft vertical separation between the aircraft. There was a breakdown of separation.
The apparent distraction of the controller by his involvement in a non-operational control room discussion would probably have adversely affected his mental 'air picture' and traffic planning. That included unintentionally clearing the flight crew of the SAAB to climb through the assigned level of the inbound 767, rather than the routinely-assigned intermediate altitude of 5,000 ft. The traffic manager's preoccupation with administrative duties meant that the monitoring and control of the distraction risk and operational activities in the control room was ineffective.
Action by the controllers to issue traffic information to the flight crew of the 767 and a radar vector and altitude limit to the flight crew of the SAAB quickly re-established the required separation standards.
It's not clear what operational changes have been made in the Tower but the consequences of distraction-causing discussions seems to me to be rather muted in the ATSB report. I appreciate that it is not its role to apportion blame, but I'd have liked to see rather stronger language about the need to prevent distractions and an explanation of how close 1.5 NM horizontal and 400 ft vertical really is in terms of flying time - too me that is way too close for comfort and represents a very serious breakdown of separation within 19 km of our largest airport. Perhaps the a/c projected flight paths were never going to intersect but the report does not explain that either.
Here is the abstract:
On 8 May 2007 at about 1858 Eastern Standard Time, a Boeing Aircraft Company 767-338 (767), registered VH-OGI, was inbound to Sydney, NSW from Melbourne, Vic. on descent to 6,000 ft and a SAAB Aircraft Company 340B (SAAB), registered VH-OLL, was departing Sydney for Moruya, NSW on climb to FL140. The distance between the aircraft reduced to 1.5 NM horizontal and 400 ft vertical separation. Separation standards as specified in the Manual of Air Traffic Services (MATS) required the provision of either 3 NM horizontal or 1,000 ft vertical separation between the aircraft. There was a breakdown of separation.
The apparent distraction of the controller by his involvement in a non-operational control room discussion would probably have adversely affected his mental 'air picture' and traffic planning. That included unintentionally clearing the flight crew of the SAAB to climb through the assigned level of the inbound 767, rather than the routinely-assigned intermediate altitude of 5,000 ft. The traffic manager's preoccupation with administrative duties meant that the monitoring and control of the distraction risk and operational activities in the control room was ineffective.
Action by the controllers to issue traffic information to the flight crew of the 767 and a radar vector and altitude limit to the flight crew of the SAAB quickly re-established the required separation standards.
It's not clear what operational changes have been made in the Tower but the consequences of distraction-causing discussions seems to me to be rather muted in the ATSB report. I appreciate that it is not its role to apportion blame, but I'd have liked to see rather stronger language about the need to prevent distractions and an explanation of how close 1.5 NM horizontal and 400 ft vertical really is in terms of flying time - too me that is way too close for comfort and represents a very serious breakdown of separation within 19 km of our largest airport. Perhaps the a/c projected flight paths were never going to intersect but the report does not explain that either.