The contract will see an additional 10 Poseidon aircraft to add to the US Navy fleet, five to Norway, and four to the UK.
The US Navy are selling on the nine aircraft to the UK and Norway through the Foreign Military Sales process.
The UK will receive their first Poseidon P-8As this year, and Norway in 2021.
The P-8A is a variant of the Poseidon that is specifically designed and produced for the US Navy and is a ”long-range multi-mission maritime patrol aircraft capable of broad-area, maritime and littoral operations”, that is militarised with maritime weapons, as well as “modern open mission system architecture and commercial like support for affordability”.
The UK has ordered nine Poseidon aircraft in total and have sent the first set of Royal Air Force personnel to Jacksonville, Florida, to begin training at the US Naval Air Station to begin the “conversion” to the P-8A.
During the next three years, the RAF will train in Jacksonville, before handling all training in-house at RAF Lossiemouth.
CXX Squadron Officer Commanding wing commander James Hanson hailed the move by the RAF to purchase the aircraft.
“This is the best maritime patrol aircraft available, a potent deterrent to our adversaries and a dependable asset for the UK and our allies,” WGCDR Hanson said.
“The commencement of our training marks the start of a new chapter for the RAF and a vital enhancement to our military capabilities in the maritime environment.”