What's behind the US-Russia Black Sea drone incident?

An unmanned US drone has crashed into the Black Sea after being pursued by Russian fighter jets.  It's the most serious incident involving the two superpowers directly since in the Ukraine war began. Is it just a one-off, or a more serious escalation?

Join host Laura Kyle.

Guests:

Pavel Felgenhauer - Defence and Military Analyst. 

Peter Lee - Author of 'Reaper Force: Inside Britain's Drone Wars'.

Alexander Titov - Lecturer in Modern European History at Queen’s University Belfast.