What happened
On 20 March 2000, a Shorts SD3-60 100 series, registration G-OLAH, was conducting a scheduled passenger flight from Aberdeen to Newcastle. While descending through FL50 in Instrument Meteorological Conditions (IMC), the aircraft was operating under a Radar Advisory Service (RAS) provided by Newcastle approach. Simultaneously, a formation of three Tornado F3 aircraft was participating in a large-scale tactical training exercise in the same region.
As the G-OLAH crew followed radar vectors to avoid military traffic, one of the Tornado F3 jets, performing high-speed maneuvers at approximately 450 knots, passed extremely close to the commercial aircraft. The encounter resulted in a horizontal separation of roughly 300 feet and a vertical separation of only 100 feet. The crew of the Shorts SD3-60 did not visually identify the fighter until it had already passed in front of them, while the military crew only detected the conflict via onboard radar moments before the encounter.
The investigation
The investigation examined the coordination between the military exercise and civilian air traffic services. It was noted that the military formation was part of a major exercise notified via NOTAM and ACN. However, the investigation found that the Weapons Controller for the E3D aircraft (MAGIC 95) had provided tactical radar information to the Tornado F3 formation before the E3D was officially "on station" and before a formal flight information service was established. This may have inadvertently led the military crew to believe they were receiving a more formal radar service than was actually in place.
Furthermore, the investigation looked at the limitations of the Radar Advisory Service in Class G airspace. While the Newcastle controller attempted to provide avoiding headings to the G-OLA crew, the high speed and unpredictable nature of the military maneuvers made these instructions difficult to execute effectively in time to prevent the close approach.
Findings
- The Tornado F3 was performing high-energy maneuvers at 450 knots, making it difficult for the civilian crew to maintain visual separation.
- The Shorts SD3-60 was operating in IMC, which limited the crew's ability to visually scan for non-participating traffic.
- The high speed and unpredictable flight path of the military aircraft prevented the effectiveness of the radar advisory vectors provided by the controller.
- The military crew was not on the same radio frequency as the civilian aircraft and was not receiving a radar service from the Newcastle controller at the time of the incident.