May be old news but i only just found it...
http://www.avon-workboats.com/page/sr54id1
SR5.4
Inboard Diesel
The Avon 5.4m Searider is in service with the worlds leading Navies and Commercial operators. The Avon Searider has been specified because of the crafts excellent sea keeping, light all up weight to fit on ships with limited davit capacity and because of its compact size making on deck stowage trouble-free.
The supply and stowage of petrol for outboard engines on some classes of ships is now proving a challenge. To overcome this Avon has developed a version of the 5.4m Searider fitted with an inboard diesel engine.
The Searider 5.4m inboard diesel version can replace an outboard Searider stowed on ship in minutes as the overall weight and stowage arrangements are similar to the outboard craft eliminating the high cost of replacing davits, stowage cradles and handling equipment.
Length 17'10" - 5.43m
Beam 6'8" - 2.03m
Tube Diameter 20" - 0.5m
Chambers 5
Aprox. Weight (inc.fuel) 1760lbs - 800kg
Capacity 6 persons
Engine Yanmar 4JH3 TE Inboard Diesel
Drive Mercruiser Alpha 1
Speed 28 Knots