On Thursday 7 September 2017 an aircraft type Dakota C53 entered the control zone of Amsterdam Airport Schiphol without permission. It flew short behind an aircraft type Boeing 747 controlled by air traffic control, approaching the Polderbaan runway for landing.
The two aircraft came closer to each other than is allowed by the separation minima. LVNL is investigating the occurrence and has reported the occurrence to the Dutch Safety Board.
What is an airspace infringement?
Internationally, an airspace infringement is defined as: “A flight into notified airspace without previously requesting and obtaining approval from the controlling authority of that airspace in accordance with international and national regulations.”
LVNL’s primary task with regard to safety is to keep aircraft separate from one another (including aircraft combined with vehicles on the ground). Air traffic control reports all occurrences that take place in practice within LVNL, in order to learn from them and to reduce the risk of such occurrences in the future. Within LVNL, all reported occurrences are investigated in order to be able to continuously improve safety.
The Dakota was flying from Groningen to Goodwood in the UK. This was a so-called VFR flight - a flight executed according to the visual flight rules (VFR). The planned route was from Groningen via Spijkerboor, a navigation beacon in the province of Noord-Holland, to Zeebrugge in Belgium and further.
As the Dakota approached the control area of Schiphol Tower Control, aircraft were landing in a southerly direction on the Polderbaan and the Zwanenburgbaan.
Without establishing contact with Schiphol Tower Control, the aircraft entered this control area at an altitude of 900 feet (approximately 300 meters). It crossed the line extending from the Zwanenburgbaan, passing beneath and behind a Boeing 737-800 which was approaching for a landing on this runway.
Efforts by air traffic control to establish contact with the crew at the time were unsuccessful. The approach controller for the Zwanenburgbaan and the tower controllers for the Zwanenburgbaan and the Polderbaan could see the Dakota on their radar screens. The aircraft was not visible from the towers.
One minute after crossing the line extending from the Zwanenburgbaan, the Dakota passed behind a Boeing 747 which was approaching the Polderbaan. The minimum distance was approximately 0.7 nautical miles (approx. 1,300 meters) laterally and 500 feet (approx. 160 meters) vertically.
A few minutes after crossing the line extending from the Polderbaan, the Dakota established radio contact with Tower Control. Tower Control pointed out to the crew that they had entered the Schiphol control area without permission and had crossed the approach area of two active landing runways.
The Dakota continued its flight without further incidents.
Results of the investigation
The investigation has shown that, after take-off in Groningen, the crew of the Dakota established contact with the flight information service of the military air traffic control - as is customary for a VFR flight. The military air traffic control provides flight information and advice in that area. However, the pilot himself is responsible for staying out of the way of other air traffic.
The border between the operating area of the military and civilian air traffic controls is halfway across the IJsselmeer. As they approached the border the crew of the Dakota should have switched to the civil air traffic control frequency. This was not done. The crew had expected the military air traffic control to advise them to avoid the control area of Schiphol Tower Control. This is not, however, one of military air traffic control’s tasks.
As the Dakota approached Schiphol’s control area, the crew requested the military air traffic control to switch to the civil air traffic control. The military air traffic control transferred the flight to the flight information service of the civil air traffic control. By this time the Dakota was flying through the Schiphol control area.
Immediately after the civil flight information service established contact with the Dakota, the crew received instructions to switch to the Schiphol Tower Control frequency. At that time, the aircraft had already passed through the approach areas of the Zwanenburgbaan and the Polderbaan.
Conclusion and follow-up actions
The incident occurred as a result of the Dakota entering the control area of Schiphol Tower Control without permission. The crew was aware of the fact that they were flying close to Schiphol, but had expected a warning from the military air traffic control. The crew switched to the civil air traffic control after the incident had already occurred.
In order to prevent incidents like these in the future, the results of the investigation will be incorporated in the further improvement of the observation of air traffic flying according to VFR in or near controlled airspace. The purpose is to ensure that measures can be taken sooner in the event of airspace infringements or impending airspace infringements. This might involve providing support to the air traffic controllers of the civilian flight information service for the monitoring of flights on the radar.
Classification: major incident