Cal's Evals » OCEAN CAT 49

Release Date: 1/1/2007

Ocean Cat 49

The advertisement for the Ocean Cat 49 in Multihull Magazine says Fastest cruising catamaran on the market. Such a claim begs testing against the analysis capability of the Multihull Dynamics, Inc website. The numbers below are for comparison of the Ocean Cat 49 with the average values for the 60 other catamarans listed on the site with the length overall of 48 to 50.9 feet. Several racing cats in this size were not included. The Ocean Cat 49 numbers, followed in brackets by the average database values, are:

Displacement: 8.04 tons [8.50 tons]

Length Overall: 49.0 feet [49.46 feet]

Length at Waterline: 48.67 feet [47.98 feet]

Beam Overall: 24.33 feet [26.48 feet]

Sail Area (Main plus 100% fore-triangle): 1053sq.ft. [1306sq.ft.]

Sail Area Displacement Ratio: 24.53 [30.89]

Beam between hull centerlines: 20.33 ft. [22.08 ft.]

Base Speed 11.52 knots [12.16 knots]

Kelsall Speed Prediction: 8.90 knots

Texel Rating: 113 [105]

Bruce Number: 1.24 [1.38]

Stability Speed: 22.02 knots [19.92]

Kelsall Stability Index: 37.38 knots

Base Speed, the best indicator of sustained speed, shows the Ocean Cat 49 to be more than 0.6 knots slower than the average for all her peers. Giving her full credit for a large genoa, for a total of 1203 square feet of sail, her Base Speed will be 12.7 knots, just short of average. So it appears the fastest claim is commercial in nature, not technical.

The cat is lighter, with smaller sail area than average. The lower weight does not compensate for the smaller sail area in performance.

On the Ocean Catamarans website photos of the boat show it to be very sleek with streamlined topsides which may permit her to point higher than others, a factor we are not able to evaluate.

Bridgedeck clearance is not stated in the specifications on the site, but one photo shows the tunnel. This photo shows what appears to be sleeping ledges on the outside of the tunnel, perhaps to accommodate the berths in the aft portion of the boat. Opinions vary on the effect of wave slamming under the bridgedeck with this sort of protrusions. Sea trials would be needed to evaluate this.

The lighter weight compensates for the narrower beam such that the Ocean Cat 49 stability speed is higher than her peers.

Calvin H. Markwood

Engineering Analyst

Multihull Dynamics, Inc

Review Written 5/5/2007