The decade-long gap in providing 'long-range ears' for the Silent Service will be plugged with the arrival of the first new maritime patrol aircraft from 2020.
The first squadron to fly the P-8A Poseidon will begin forming at Lossiemouth next year as a £3bn investment in the new aircraft - a military version of Boeing's workhorse airliner, the 737.
Nine Poseidons are being acquired by the MOD under the 2015 Defence Review, with the principal aim of protecting the UK's nuclear deterrent and the nation's two new carriers, scouting for hostile submarines - and surface threats - using sonobuoys and radar respectively.
Armed with torpedoes and anti-ship missiles, the P-8As will also support search and rescue missions and gather general intelligence.
Although they will be operated by the RAF, firstly with 120 Squadron (successor to the most successful submarine hunting formation in the air force in WW2) and, from 2021, 201 Squadron (which traces its history back to the Royal Naval Air Service's 1 Squadron, formed two months into WW1), the Poseidons will also carry Royal Navy personnel.
Their entry into service fully plugs the gap left by the retirement of the Nimrod MR2, which last flew in March 2010, and the decision to scrap its horrendously over-budget and delayed replacement, the Nimrod MR4A.
To keep the flame of maritime patrols alive since 2010, British crews have been flying with similar squadrons in Australia, New Zealand, Canada an the USA.
And Whitehall has signed agreements with the US and Norwegian military to closely co-operate on operating their P-8As over the North Atlantic.
Around £400m will be invested in Lossiemouth to host the new jet, which will require more than 400 ground and air crew to support its operations.
