What happened
On July 30, 1998, at approximately 10:25 local time, a serious air traffic safety incident occurred approximately 18 km west of Kuopio Airport at an altitude of roughly 1,700 meters. The incident involved three aircraft: a Gates Learjet 35A (registration V-01), which was performing a navigation flight from Turku to Kuopio carrying the President of the Republic of Finland and their entourage, and two F-18C/D Hornet fighter jets (registrations HN-422 and HN-464) conducting a training mission from Kuopio.
The aircraft crossed paths on intersecting flight paths at a very close distance. Radar data indicates that at the moment of closest approach, the lateral separation between the aircraft was approximately 1,300 meters, while the vertical separation was only about 40 meters. There were no injuries or damage to the aircraft involved.
The investigation
The investigation examined the coordination between different air traffic control units and the functionality of the EFES 2+ Pommery system, which is used to transfer flight information between the Tampere Area Control Centre and other units. Investigators reviewed radar recordings, radio communications, and flight plan data. The investigation also looked into the handling of flight information transfers between sectors, specifically regarding how aircraft information is updated in the local controller's system.
Findings
- The primary cause of the incident was a failure to properly hand over flight information for the V-01 Learjet to the Kuopio approach controller.
- The EFES 2+ Pommery system did not show the Learjet as an active flight in the Kuopio sector, meaning the controller had no prior information regarding its arrival or flight path.
- Because the flight information was not updated, the controller was unaware that the V-01 was entering the active military training area (MIL CTA).
- The two F-18 Hornet jets were appearing on radar only as unidentified tracks (without specific callsign labels) because their identification codes had changed during their mission, further complicating the controller's situational awareness.
- The controller had to manually search through paper flight plan files to identify aircraft, which delayed the recognition of the approaching Learjet.