Unusual: an Italian Air Force Gulfstream E.550 CEW (reg. MM62293) returns to Pratica di Mare AB after a 8 hours surveillance mission in the Black Sea theatre.
Unlike the other times when it was possible to track the entire mission this time the ADS-B transponder was switched off over Bulgaria.
Hypothesis, that the mission took place over the Black Sea and not just on the Romanian coast?
Remember that four Italian Air Force Eurofighter Typhoon fighters are based at the Mihail Kogalniceanu airbase in Romania.