Investigation
The Swedish Accident Investigation Authority (SHK) investigated an accident involving a Boeing 737-800 aircraft, registration SE-RRF, and two JAS 39 Gripen fighter aircraft flying in formation. The incident occurred in the airspace over Östergötland, Sweden, on 18 June 2025. The investigation was conducted in accordance with Regulation (EU) No 996/2010 and Annex 13 to the Chicago Convention.
Sequence of Events
The passenger aircraft was en route to Stockholm/Skavsta Airport while the two JAS 39 Gripen aircraft departed from Linköping-Saab Airport. In the airspace above Östergötland, the Traffic Collision Avoidance System (TCAS) on the Boeing 737-800 generated a Resolution Advisory (RA), instructing the crew to perform an evasive maneuver to avoid a potential collision with the fighter aircraft. The maneuver was executed as directed. All aircraft involved were being operated in accordance with applicable regulations and procedures, and the clearances issued by Air Traffic Control (ATC) were complied with. At no time was there any actual risk of collision.
Injuries to Persons
During the evasive maneuver, one cabin crew member was seriously injured. Other occupants were seated with seat belts fastened.
Damage to Aircraft
The source does not specify any damage to the aircraft.
Aircraft Information
The passenger aircraft was a Boeing 737-800, registration SE-RRF. The fighter aircraft were two JAS 39 C Gripen aircraft. The Boeing 737 was equipped with a TCAS collision avoidance system, which generated the resolution advisory.
Cabin Crew Actions
At the time of the maneuver, the cabin crew were in the process of securing the cabin for landing.
Meteorological and Communication Information
The source does not provide specific meteorological conditions. Communications between aircraft and ATC were part of the investigation, with deviations from standard phraseology noted as contributing to misunderstandings and ambiguities.
Analysis
The SHK analysis noted that the aircraft were maneuvered in accordance with regulations and clearances. The TCAS RA was triggered despite no collision risk, and the investigation examined whether air traffic controllers could prevent TCAS activation when fighter aircraft operate near civil aircraft. The analysis also addressed why the cabin crew member was injured, deviations in phraseology, and the need for expanded TCAS training.
Conclusions
The SHK report includes findings but does not explicitly state a probable cause. The investigation did not assign blame or liability.