A pilot from 6 Squadron, RAF Lossiemouth in front of a line of Typhoon aircraft (Picture: Crown Copyright).
The runways at RAF Lossiemouth will be resurfaced as part of a £75m upgrade.
It is to prepare the Scottish base for the arrival of nine P-8A Poseidon Maritime Patrol Aircraft, the first of which is expected to arrive in 2020.
Home to four fast-jet squadrons flying the Typhoon, it has been some time since the Moray base has regularly operated a larger aircraft such as the Poseidon.
The contract for the work has been awarded to VolkerFitzpatrick Ltd by the Defence Infrastructure Organisation.
Other improvements include accommodation for personnel, a new Air Traffic Control Tower, upgrades to drainage and electrical supplies, and upgraded facilities for IX (Bomber) Squadron which moved to RAF Lossiemouth this year.
Group Captain Jim Walls, Station Commander RAF Lossiemouth, said: “The P-8A Poseidon aircraft and its crews will also be operating 24/7 to safeguard our seas.
"Poseidon is world-class in its roles of maritime surveillance and submarine hunting."
It is expected the work will be finished by spring 2021.