Pictured in the foreground is a Royal Air Force CH-47 Chinook flying with two USMC CH-53 Sea Stallions during a twilight training sortie in Arizona. Two Royal Air Force Chinook CH-47 helicopters from 27 Sqn, RAF Odiham located in Hampshire (UK), deployed to Marine Corps Air Station Yuma in Arizona, USA to take part in a twice-a-year training a development programme known as WTI. WTI stands for Weapons and Tactics Instructor and is a course that aims to develop aircrew – both pilots and NCO’s – to an instructional level. It is conducted in the Marine Aviation Weapons and Tactics Squadron One (MAWTS-1) building and the vast amount of desert terrain training areas within Arizona. Following completion of this, they will then be able to transfer and disseminate these skills to those in their chain of command. Not only are the aircrew trained to instructional level, but they are also able to practise and develop niche skillsets that would normally only be developed in active conflicts. An example of this is deploying to a Forward Arming and Refuelling Point (FARP) in order to provide rapid refuelling and arming to other air and land assets in remote locations, often far from their main operating base. The CH-53 Sea Stallion operated by the US Marine Corps is a heavy-lift transport helicopter and has seen considerable use in warzones and served in various conflicts during its service.