Bulgarian and Romanian air force crews ran a joint flight drill called "Blue Bridge 2026" to work on coordination between the two countries in cross-border air policing, the defence ministry's press office says.

The drill had two phases. In the first, Romanian F-16 fighters took off under the air policing programme after a C-27J Spartan military transport plane strayed off its flight path. Once the Romanian pilots had the aircraft under control, they handed the target over to Bulgaria's duty air defence forces.

From there, a pair of Bulgarian air force MiG-29s took over and forced the C-27J Spartan to land at Graf Ignatievo airbase. In the second phase, the crews ran the same drill the other way round, with the "intruder" plane forced to land at a designated airport in Romania.

The drill has been held every year since 2012 and aims to help the Bulgarian and Romanian air forces work better together. In September 2026, the Bulgarian air force took part in a similar drill with Greece called "Green Bridge 2026", in which crews from both countries practised handing over and taking control of an intruder aircraft.