The Royal Air Force's new submarine hunter aircraft fleet is now complete after welcoming its ninth P-8A Poseidon jet.
The arrival of the final jet at RAF Lossiemouth means the RAF has a full maritime patrol fleet for the first time since 2010.
The RAF airfield in Moray, Scotland, has been undergoing an upgrade costing £360m in total ahead of the arrival of the Poseidon fleet.
It includes a major revamp to the airfield and the construction of a new facility.
Here's all you need to know about the aircraft.
Poseidon's role and capabilities
P-8As are equipped with sensors and weapons systems designed for anti-submarine warfare, and will also carry out surveillance and search and rescue missions, according to the RAF.
They fill the role left by the RAF's previous maritime patrol aircraft, the Nimrod, which was retired in 2010.
Based on the Boeing 737-800 airliner, the contract to develop the P-8A for the United States military was granted in 2004, and the first Poseidon flew in 2009.
Watch: An RAF Poseidon flies with the Red Arrows for the first time.
The US Navy began operating the P-8A in 2013 and variations of the aircraft are in service with the Indian Navy and the Royal Australian Air Force.
The RAF received its first P-8A in October 2019 during a ceremony in the United States.
Eight more aircraft have followed, with the fleet costing the UK £3bn in total.
The aircraft is equipped with a range of search and tracking systems, including:
- An APY-10 radar providing high-resolution mapping.
- An acoustic sensor system.
- An IR turret and electronic support measures (ESM).
It also carries torpedos.
Defence analyst Tim Ripley, from Jane's Defence Weekly, told Forces News in 2020: "For 10 years, the RAF has not had a maritime patrol aircraft so this is a major development.
"It is a different type of maritime patrol aircraft. It's not built in the way that the Royal Air Force has operated maritime patrol aircraft in the past.
"It's a converted airliner, so it's not designed to operate at a low level, which is the way that previous generations of British maritime patrol aircraft have operated," he added.
- Powerplant: two 27,000lb st (120kN) CFM International CFM56-7 turbofan engines
- Length: 129ft 6in (39.5m)
- Height: 42ft 9in (13.03m)
- Wingspan: 123ft 6in (37.7m)
- Maximum take-off weight: 189,200lb (85,820kg)
- Maximum speed: 490kt (907km/h)
- Ferry range: 4,500 miles (7,242km)
- Service ceiling: 41,000ft