MOSCOW, November 11. /TASS/. A NATO reconnaissance drone once again lost contact with its base while on a flight over the Black Sea waters, an air traffic control source has told TASS.

"The NATO-owned and Italian Air Force-operated RQ-4D Phoenix reconnaissance drone took off from the Sigonella air base in Sicily and signaled communication problems while over the Black Sea," the source said.

He added that the drone is currently continuing to cruise in the southern part of the Black Sea from west to east and back at an altitude of nearly 16 kilometers.

The source did not clarify the possible cause of the communication failure. However, he recalled that similar incidents involving RQ-4D Phoenix drones have already taken place over the Black Sea on September 24 and 16, and also on July 21, when the aircraft ultimately managed to land at the Sigonella air base after several hours, following an extended period of cruising over the Mediterranean Sea as well.

The source said that one of the functions of the Northrop Grumman RQ-4D Phoenix is to collect images from large areas of land and transmit the data in real time.