Designed to be carried on the deck of larger ships for more distant work, RV Callista will spend most of its life in the Solent and along the south coast of Britain. It is capable of covering 400 nautical miles, or 40 hours of operating time between fuel stops.

Propulsive power for the 46 ton craft is supplied by twin 650hp Scania D12 engines, one in each hull driving an 890mm Radice S4 bronze propeller through a Twin Disc MGX 51124A gearbox with a ratio of 2.04:1. The electronic throttle control system is the multi-station Twin Disc EC300 with express mode and hand held remote control.

The vessel is capable of a maximum speed of 16.5 knots.

'From an operational point of view, Callista is exceptional, says Graham Etheridge. 'She performs extremely well and her sea keeping is particularly good. To allow for pinpoint accuracy when deploying or retrieving equipment we have five control stations located around the boat from maintains a constant engine speed and enables us to run extremely slowly by using valves in the transmission to vary the speed of the propshaft.'

RV Callista's one per hull engine layout pleases the boat's engineer, Andy Smith. He said, 'It's very good, well thought through, with everything in just the right place. That gives me particularly good access to the engines. The whole thing has been designed by people who obviously understand the issues from an engineering point of view. This makes routine maintenance very straightforward and, I'm delighted to say, gives me an easy life.'

Speaking of engine choice, Graham Etheridge added, 'There are a number of Scania powered workboats operating near to us and their owners speak very highly of them.

Also, Scania provides good service back-up both locally and internationally, which was another key factor for us.'

MJInformation No: 21911