Incident involving HMS Prince of Wales fighter comes days after landmark joint drills on Japanese carrier and delivery of first F-35Bs to Japan Air Self-Defense Force

US Defense Security Cooperation Agency clears potential $4.1 billion order for the aircraft

A Bell and Boeing tilt-rotor aircraft belonging to the US Air Force crashed off the coast of Yakushima after potential material failure, according to a preliminary investigation

Air refueling aircraft is part of an order for four jets with Boeing and is the first delivered outside the US

The aircraft will be delivered to Japan Air Self-Defense Force (JASDF) in 2021 as part of an order for four units