The RAF is taking the lead on a large-scale military exercise to prepare air forces for peer adversaries.
Italian, German and US militaries are joining Exercise Cobra Warrior throughout September, led by the Air and Space Warfare Centre at RAF Waddington in Lincolnshire.
As Russia's invasion of Ukraine keeps worldwide security on alert, interoperability drills between allied nations take on even greater importance – this one involving several bases.
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Forces News watched some of the jets, which include Italian Typhoons, German Tornados and US F-16s, return from high-intensity, large force tactical training over the North Sea and spoke to those at the heart of the drills.
Mock operational airspace can include the border between Scotland and England, with a 'blue' and 'red' force formed of coalition pilots from different nations, with the blue side looking to "fight their way toward" surface-to-air missile systems (SAMs) belonging to the reds.
Typically, the SAMs will be located at RAF Spadeadam in Cumbria, with up teams of 50 aircraft taking on another team of 25.
"Today we were in the role of attacking a target, while the British Typhoons were defending us from air-to-air threats," said Major Marco Setini, Detachment Commander, Italian Air Force.
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Group Captain Andrew Burton, Deputy Commander of the Air Space Warfare Centre, RAF Waddington, said: "We, as the exercise staff, set challenging missions, we set a threat environment."
He said "interoperability doesn't come around by chance" and stressed that flying missions are vital to help nations work together, otherwise "on the day we need to, we won't be able to".
"Hopefully that sends a message out, that we're ready if we're called on," he added.
NATO has set itself in a defensive posture, and many of those taking part in Ex Cobra Warrior are also flying missions in support of the alliance as Russia's war against Ukraine continues.
Lieutenant Colonel Stefan Kollner, Detachment Commander, German Air Force, describes the drills as "the icing on the cake" for his personnel.
The three-week exercise happens twice a year and ends on 25 September, and also includes early warning aircraft and air-to-air refuel tankers.