The crew of the UK Royal Navy's Elizabeth-class (QE) aircraft carrier, HMS Queen Elizabeth, has switched on the vessel's S1850M radar for the first time.
The flashing up of the long-range radar was part of ongoing preparations to ready the warship for sea next year.
Weapon engineers PO Ian 'Mac' McDonald said: "Having been a part of the long range radar programme since it was delivered to Rosyth back in October 2013, it's very satisfying to see it 'turning and burning' - a milestone nearly two years in the making.
"It shows both the progress of the ship's radar section in conjunction with mission systems, and that Queen Elizabeth is another step closer to becoming an operational warship."
Designed to provide a three dimensional and long-range picture, the radar can track up to 1,000 contacts up to a range of 400km from the vessel.
During the restricted operation, the radar compiled an air picture, tracking aircraft on approach to Glasgow airport, which is 40 miles to the west of Rosyth, as well as transatlantic traffic to and from the rest of the UK.
The radar has not been switched to full power yet due to the current power and safety limitations.
The 300m-long HMS Queen Elizabeth will boost sustained operations, and has an air-wing of up to 40 aircraft, in addition to AgustaWestland AW101 Merlin HM2 multi-role rotorcraft and Merlin HC4 amphibious support helicopters.
The navy is expected to begin sea trials for the carrier in August 2016, followed by commissioning in May 2017.
Image: The S1850M radar is a large black slab sitting on top of the HMS Queen Elizabeth's forward island. Photo: courtesy of UK Royal Navy.