HMS Queen Elizabeth, a 280-metre, 65,000-tonne aircraft carrier is due to set out from Rosyth on the Firth of Forth - subject to final checks, tides and the Scottish weather.
The behemoth, which is set to be the nation’s future flagship, and her 700-strong ship’s company are ready to undertake her maiden sea trials over the summer.
However the vast vessel must first get out to sea - a major operation where timing is key.
After waiting until high tide to leave the naval dockyard, the carrier must then wait for the tide to lower to pass under the Firth’s famous bridges.
Weather conditions must also be favourable as the four-acre military operating base sets sail.
During her estimated 50-year working life, HMS Queen Elizabeth could be pressed into action for various work such as high intensity war fighting or providing humanitarian aid and disaster relief anywhere in the world.