The Islander 37 MS Sailboat
Specs & Key Performance Indicators

Built on the same hull as the Islander 37 sailboat, the Islander 37 MS was designed by American naval architect Bruce King and manufactured by Islander Yachts, a shipbuilding company located in Costa Mesa, California.

The boat was introduced in the 1960s and aimed to combine performance-oriented design elements with practical features necessary for extended voyages. A kit version was sold as the Yachtcraft 37.

The Islander 37 MS

Published Specification for the Islander 37 MS

Underwater Configuration: Fin keel & spade rudder
Hull Material: Fiberglass
Length Overall: 37 feet (11.28 meters)
Waterline Length: 28 feet (8.53 meters)
Beam: 11.17 feet (3.40 meters)
Draft: 5.5 feet (1.67 meters)
Rig Type: Masthead sloop
Displacement: 13,400 lbs (6,078 kg)
Designer: Bruce King
Builder: Islander Yachts
Year First Built: 1967
Year Last Built: 1970
Number Built: Approximately 55

Published Design Ratios for the Islander 37 MS

Sail Area/Displacement Ratio (15.8): This ratio falls just below 16, suggesting that the sailboat is somewhat underpowered. This means that, in terms of sail power relative to its weight, it may not perform as sprightly or responsively as boats with a higher ratio. Therefore, while it may handle moderate winds adequately, it could struggle in lighter conditions where more sail power would be beneficial.

Ballast/Displacement Ratio (33.6): At 33.6, this ratio is below 40, indicating that the boat is less stiff compared to boats with a higher ratio. This suggests a moderate ability to stand up to the wind without excessive heeling (leaning to one side under wind pressure). However, as mentioned, this does not account for the distribution of ballast, such as whether it's in a deeper fin keel or a shallow draft, which can significantly affect actual performance and stability.

Displacement/Length Ratio (268.3): Situated within the moderate displacement category, the Islander 37 MS promises sufficient stability and somewhat heavier handling characteristics. It won't be as nimble or accelerate as quickly as lighter displacement boats but offers a handy compromise between performance and comfort, especially in heavier seas.

Comfort Ratio (30.8): With a comfort ratio indicative of a moderate bluewater cruising boat, the Islander 37 MS is potentially suited for longer passages where comfort in varied sea conditions is a consideration. This suggests the boat is designed to handle moderate sea conditions with less motion discomfort for the crew, making it a good choice for extended cruising or liveaboard scenarios.

Capsize Screening Formula (1.8): The low score here implies good seaworthiness and a reduced likelihood of capsize in adverse conditions, reinforcing its suitability for offshore sailing. This is particularly reassuring for cruisers aiming for longer or more challenging voyages.

Limitations and Theoretical Considerations:

The Ballast/Displacement Ratio primarily reflects the boat's initial resistance to capsizing but does not indicate the final stability, which could be compromised depending upon the actual design and distribution of ballast.

Ted Brewer’s Comfort Ratio tends to favour traditional heavy displacement designs, and might not fully represent the comfort levels of more modern, light-displacement designs with different hull shapes and configurations. Thus, while indicative, it doesn't necessarily capture all elements affecting crew comfort, such as damping characteristics and dynamic behavior in varying sea states.

Read more about Design Ratios...

In summary, the Islander 37 MS appears to be a versatile sailboat that, while not particularly high-performing in terms of sail power, offers a good blend of stability and comfort suitable for both coastal cruising and longer voyages, assuming that the actual design and build qualities align with these theoretical indications.

The above text was drafted by sailboat-cruising.com using GPT-4 (OpenAI’s large-scale language-generation model) as a research assistant to develop source material; we believe it to be accurate to the best of our knowledge.