The Royal Navy's new aircraft carrier HMS Queen Elizabeth has left Portsmouth for rotary wing trials.
The aim of the helicopter trials is to determine the conditions in which aircraft can safely operate while at sea on the carrier.
Information about landings, take-offs and manoeuvres will be taken during different weather conditions - this data must be taken in order for the ship to be declared safe to operate the aircraft.
The tests will be followed by F35B Lightning II trials later this year.
This is how the departure unfolded:
The largest and most powerful ship ever built for the Navy left the city's dockyard at 12:40pm local time.
Chinook helicopters landed on board the carrier for the first time during Friday morning.
These will be joined by two Merlin Mk2 aircraft.
Captain Jerry Kyd, Commanding Officer of HMS Queen Elizabeth, said: "After the excitement of our commissioning ceremony in December, my ship’s company and our industry partners are looking forward to taking the ship to sea to conduct first of class rotary wing flying trials.
"These trials will involve operating different types of helicopter from the ship in all weather conditions and fully testing the myriad of on board systems that are designed to support aviation.
"This is an important milestone in the ship’s progression towards embarking the F35-B Lightning jets later this year, and ultimately the achievement of carrier strike capability."
HMS Queen Elizabeth left her home port for the first time last May, returning last November after conducting "successful sea trials".
The Royal Navy confirmed this week that a sprinkler system on board the ship was "inadvertently triggered" on Sunday, however, causing some damage in one of its hangars.
The carrier's departure coincides with a final-ever visit by HMS Ocean in Portsmouth - the vessel which, it emerged last night, would not receive a reprieve from plans for it to be decommissioned.
Cover image: Royal Navy.
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