Incident Details
On 14 January 2015, an Airbus A320 and a formation of four Polish Air Force F-16s were involved in a loss of separation incident in the vicinity of the Warsaw Flight Information Region (FIR EPWW). The A320 was climbing after departure, en route to flight level (FL) 320, and was in communication with a General Air Traffic (GAT) area controller. The F-16 formation, operating as Operational Air Traffic (OAT), was climbing from FL 300 to FL 310 on a heading of 270 degrees, having departed from the TSA 2 zone. As the A320 passed through FL 280, the radar system generated a Conflict Alert on the GAT controller's display, indicating a potential conflict with the F-16s. The GAT controller instructed the A320 crew to turn left 15 degrees and stop the climb at FL 300. Meanwhile, the OAT controller, after establishing contact with the F-16 formation at FL 300, ordered them to turn to a heading of 180 degrees and continue climbing to FL 310. The minimum separation between the aircraft reached 6 nautical miles horizontally and 1,700 feet vertically, against the required 10 NM or 2,000 feet.
Findings
The investigation, conducted by the air navigation service provider, revealed several contributing factors related to air traffic management. The GAT controller was on his first shift after two days off, the OAT coordinator was also returning after two days off, and the OAT controller was on his first day after one day off. The number of open sectors was deemed appropriate for the moderate traffic volume. A review of the controllers' qualifications found that all held valid licenses and medical certificates, with recent refresher training. The incident occurred while three groups of F-16s were simultaneously departing TSA 2. The lead F-16 pilot had requested a direct flight to base due to low fuel, and the OAT controller, influenced by the urgency, authorized a westerly heading. Upon recognizing the conflict, the OAT controller directed the formation to a southerly course. The separation loss happened while the F-16s were already turning to the west. The ACC controller correctly responded by instructing the A320 to turn west and stop its climb. Post-incident observations noted that during work on two sectors with high military and GAT traffic, radar displays became cluttered, increasing controller workload. The OAT position had a third sector available but unused due to staffing shortages. The color coding of GAT and military tracks on the same display was identical (pink), reducing readability. There was no Letter of Agreement (LoA) with the military to standardize coordination. OAT controllers handled multiple frequencies, and the inability to use offset capability complicated communications, sometimes requiring repeated transmissions. The OAT personnel requested simulator-based refresher training during periods of lower military activity.
Probable Cause
The probable cause of the incident was errors in ATM work.