Dave King was coxswain of Forth Ports’ existing vessel, the Calatria, and his widow Liz was asked to perform the honour of carrying out the naming ceremony of the new boat - which was blessed by the Port of Grangemouth’s chaplain, the Rev. Joe O’Donnell.
The nine-metre long vessel will be used to survey water depths within and on the approaches to the company’s five ports in the River Forth and at the Port of Dundee on the River Tay.
She will also monitor the depth of the shipping channels within both estuaries.
The Forth King has been fitted with the latest multibeam sonar equipment, which carries out bathymetric surveys which produce a 3D image of the riverbed, and with a Lidar (radar using laser beams).
She is said to be quieter, cheaper to operate and more environmentally friendly than preview survey vessels.
Port of Grangemouth chief harbourmaster Alan McPherson said: “It is fitting that the Forth King carries Dave’s name.
“He was a great loss to everyone who knew him, and his love of the river lives on in our new survey vessel.
“The Forth King will expand our surveying capabilities, not just in terms of the locations it can go to but in the range of services it can provide.”