Biden has sent the E-6B Mercury which is an American military strategic control and communications aircraft. It is a command center for the US Navy. It is also called “judgment day aircraft” because it is used for communication with nuclear submarines for the purpose to control any launch of intercontinental ballistic missiles. These are the submarines of the Ohio class. Each submarine can have up to 24 Trident II D5 missiles, capable of carrying nuclear warheads, on board.
I cannot verify that 365 attack planes were sent. It appears that only squadron 365 may have been sent. All I can verify is that the US has been sending Air Force F-35 fighter jets to Estonia, Lithuania, and Romania.
