On top of that, Air Force Headquarters was not informed of the exercise, according to the Swedish Accident Investigation Board (Statens Haverikommissionen) on Thursday.
Two Saab JAS 39 Gripen fighter planes were accidentally granted permission to fly through a training area outside the southeastern island of Öland on October 21st last year. At the time, the Swedish Armed Forces (Försvarsmakten) were shooting live ammunition from a ship. The mistake was discovered in time and the shooting stopped.
The board's report on the incident reveals serious shortcomings. A lack of routines at the Swedish Transport Agency (Transportstyrelsen), Swedish Civil Aviation Administration (Luftfartsverket, LFV) and the Armed Forces culminated in the event, according to the board's Agne Widholm.
The pilots of the planes received clearance from civilian air traffic control in Stockholm to fly over the military training area outside Öland. However, air traffic control was unaware of an exercise in the area.
The commanders of the exercise detected when the planes approached the training area with the help of radar. They immediately ordered the suspension of the live ammunition shootings and the planes were allowed to pass through the area.
The military training area was monitored by two flight control centres in Malmö and Stockholm.
"Malmö knew about the exercise, but not Stockholm. When the planes approached the exercise area, Stockholm took over and did not know an exercise was going on," said Widholm.
Investigators do not believe that the planes were at risk of getting shot down because the error was discovered in time.
During the investigation, it emerged that the incident outside Öland was not the first.
"There have been several other similar incidents and there is a potential risk every time it happens," said Widholm.
Over the last two years, there have been 26 reported cases of an aircraft or helicopter flying into a dangerous military training area.
The investigators have proposed that the Transport Agency, LFV and Armed Forces review their procedures and instructions in order to minimise or entirely eliminate these types of incidents.