Loss of separation Schiphol

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On Friday 27 July, in the approach area of Amsterdam Airport Schiphol, a sports aircraft crossing this area and an aircraft departing from the so-called Zwanenburgbaan (18C) came closer to each other than was intended. LVNL (Air Traffic Control the Netherlands) conducts an investigation into this incident itself and reported it to the Onderzoeksraad voor Veiligheid (Dutch Safety Board).

 

Occurrence investigation

 

LVNL's primary function with regard to safety is to keep aircraft at a safe distance from each other (including aircraft being towed by ground vehicles). Any occurrences that may occur in practice are reported to LVNL by the air traffic controllers to ensure lessons can be learned and to minimize the risk of similar occurrences occurring in the future. All reported occurrences are investigated within LVNL in order to continually optimize safety in the aviation sector.

 

 

Separation near airports

Visual separation is the method used within the local airspace around an airport (known as the control zone) provided that the air traffic controllers can see both aircraft or both pilots can see each other's aircraft.

 

More information about loss of separation can be found here.

 

Situation description

A Diamond DA-40 aircraft was approaching Schiphol from the east and requested clearance from air traffic control to cross the local control zone from east to west. The tower controller granted him permission to do so. Upon approaching the control tower, the Diamond pilot requested permission to perform a 360 degree turn around the tower. This request was granted on the condition that the Diamond remained well clear of the Zwanenburgbaan (runway 18C-36C) and the Buitenveldertbaan (runway 09-27).

 

On runway 18C-36C, a Boeing 767-300 was ready to take off in a southerly direction and requested take-off clearance from the control tower. Before receiving take-off clearance, the pilot of the Boeing was informed of the fact that he may see a small private aircraft to the left of his expected take-off route and that the aircraft would remain clear of this route.

 

The Diamond pilot then requested permission to continue his flight in a westerly direction. This request was granted by the control tower provided that the Diamond remained behind the Boeing during its take-off. Despite confirming these instructions, the pilot proceeded to fly in front of the Boeing at an altitude of 1,000 feet (over 300 meters) as the Boeing was proceeding with its take-off.

 

The supervisor informed the controller of the Diamond pilot's failure to comply with the instructions issued. Due to the reaction times and the positions of the aircraft in question, no additional action was taken. According to the radar information, the Diamond was flying approximately 500 meters to the west of runway 18C-36C at an altitude of 1,000 feet at the moment that the Boeing's nose wheel left the ground.

 

Both aircraft completed their flights without further incident.

 

 

Conclusion

 

The occurrence was caused by the Diamond pilot failing to follow the course specified by the air traffic controller. Due to the positions of the aircraft, additional instructions were not required. Despite this, the minimum horizontal and vertical separation between the two aircraft and the fact that the Diamond crossed the flight path of the Boeing just after the Boeing started its take-off mean that this situation must be classified as a serious incident.

 

Classification: serious incident