Catamarans 7m, 8m, 9m

DC 7, 8 and 9m range (designed for outboard engines)

Formerly Colne Catamarans, all existing guarantees and contracts on boats built by Colne Catamarans, will be honoured by Orwell Boats.

The DC 7, 8 and 9m range (formerly Colne Catamarans) is highly suitable for: Commercial Fishing, Aquaculture, Angling, Charter, Diving, Survey, Committee Boats, Sight-seeing and Passenger vessels, amongst many other uses.

What benefits could a new DC 7, 8 and 9m offer, compared to a mono-hulled vessel of a similar size?

  • Up to 40 times better stability compared to a mono-hull
  • Considerably less rolling around
  • Up to 50% more deck space
  • Increased and safer deck carrying capacity
  • Easier and safer when working on deck
  • Virtually unsinkable
  • Reduced running costs, maintenance and down time
  • Higher speeds compared to equivalent power from diesels
  • Reduced fuel consumption
  • Minimal through-hull fittings, reducing the risk of flooding
  • Much reduced survey fees
  • Low license requirements
  • Easy single-handed operation
  • Very shallow draft
  • Fewer aches and pains after a rough trip

Compared to our nearest competitor, DC 7, 8 and 9m are wider and therefore more stable, have a higher carrying capacity, are more competitively priced and have higher build quality.

If you would like a brochure and price list, a trip aboard one of these boats, to see the benefits for yourself, or a full written quotation to meet your specific requirements, please contact us.

Hull design

Why choose a DC 7, 8 and 9m over other catamarans?

These lighter catamarans are designed with little rake on the stem, a very full forefoot and a full hull dead rise, this gives a catamaran hull the required full buoyancy forward all catamarans need when heading into weather, or they will slam on the bridge deck badly.

Many designs on the market have a finer entry bow and weak forefoot to improve speed and this does work to a degree but only in very calm conditions, however as soon as any weather is experienced, the bows bury into the seas and bridge deck slamming starts, which reduces speed and sea keeping dramatically.

With the full hull design, some light slamming is experienced on the hulls as they are so full, but this is far more acceptable for maintaining average speed, fuel efficiency and comfort.

These catamaran hull design rules apply world over, so if any boat designers or builders suggests their catamarans do not slam in any way, we suggest there boats are tested out in poor weather conditions, so this can be experienced first hand before any purchase is made.

Outboards vs diesels fitted in small catamarans

​Andrew Craig has designed and built well over a 150 catamarans up to 16m, fitted with both inboard and outboard engines. He has shown that lighter boats fitted with outboard engines, as well as being faster, are considerably more fuel efficient, and less expensive to build. It is important to note that fitting diesel engines to a boat of this size can increase its weight by around 50%, as diesel engines are heavier, require engine beds, stern gear, steering gear, internal fuel tanks and require much more wiring and plumbing. While a diesel engine is more fuel efficient, when compared with an outboard engine of the same size, a lighter boat fitted with the same size outboard engines has an improved power to weight ratio.

Example: a DC 8m catamaran fitted with 2 x 75hp outboards will weigh around 3 tons, giving 50hp per ton with a top speed of around 23 knots. An 8m catamaran fitted with 2 x 75hp diesels will weigh at least 4.5 tons with just 33hp per ton, giving a top speed of around 12 knots.