Nimrod R1: 'Eyes and ears of RAF'
As the last two of the RAF's Nimrod R1 surveillance planes are decommissioned at RAF Waddington, BBC News looks back at their role.
The aircraft have been operated by 51 Squadron since 1974. They had recently been on operations in Libya with UK and Nato forces.
Their main role has been to support the RAF's reconnaissance and intelligence-gathering operations.
They have seen active service in conflicts including Afghanistan and Iraq, and during the Cold War.
The Nimrod R1 was operated by a four-man flight crew with 24 surveillance operators and a mission supervisor. It was developed from the Comet civilian airliner
There were also 24 reconnaissance crew working on the sophisticated surveillance equipment commanded by a mission supervisor.
The Nimrod could fly at high speed and spend time in operations for long periods at slower speeds while on surveillance. It could intercept electronic communications including those made by mobile phone.
It also had the capability of air refuelling, helping its long-range capabilities.
Air Marshal Cliff Spink, a former RAF pilot and ex-station commander at RAF Coningsby in Lincolnshire, said: "These aircraft have been the eyes and ears of all our operations.
"Having that vital intelligence, not only in the hot wars but also the cold wars, has been absolutely vital to us."