Ocean Bird 30 Information, Review, Specs

Sailing Performance & Handling

The Ocean Bird 30 was designed with a heavy emphasis on stability and safety over the raw, flighty speed often associated with modern racing trimarans. Unlike many multihulls that use a bridge-deck cabin, Westell utilized a webless steel-beam frame to connect the hulls, which minimizes windage and prevents the "aerofoil lift" that can lead to capsizes in extreme conditions. As noted in a classic report by Design Journal, the boat's design ensures that the leeward outrigger provides immediate righting moment as soon as the boat heels, a sensation described by early testers as more akin to a very stiff monohull than a typical catamaran.

Under sail, the masthead sloop rig is easily managed, though the vessel's displacement of approximately 10,000 lbs makes it relatively heavy for a 30-foot multihull. This weight, while limiting light-air performance, contributes to a predictable and seaworthy motion in heavy weather. The use of a daggerboard allows for excellent upwind tracking, while the wave-piercing design of the low-buoyancy amas helps the boat maintain momentum through chop.

Interior Comfort & Variations

Because the living quarters are entirely contained within the central hull, the interior of the Ocean Bird 30 feels remarkably similar to a narrow-beam 30-foot monohull. The layout typically features two V-berths in the forward cabin, followed by a heads compartment with a marine toilet and washbasin. The main saloon incorporates a dining area that can often be converted into additional berths, alongside a functional galley and a dedicated navigation station.

Variations of the design were refined through "Mark I" and "Mark II" iterations, with minor changes to the interior joinery and the folding mechanism's bracing. A larger sibling, the Ocean Bird 35, was later introduced to offer more voluminous living spaces and improved bridging between the hulls, but the 30 remains the most common model found on the secondary market.

Popular Mentions & Media

The Ocean Bird 30 gained significant credibility in the early 1970s when it participated in the Yachting World Rally for cruising yachts. It was notably the only multihull to finish in the top ten of that competition, proving that a folding trimaran could compete with established cruising monohulls in terms of reliability and offshore capability. This performance helped dispel some of the era's skepticism regarding the structural integrity of multihulls.

Known Issues & Buyer’s Checklist

Prospective owners should pay close attention to the boat's unique structural elements, which are now over 50 years old.

• Pivot Pin Wear: The "swing-wing" mechanism relies on large vertical pins and conical bearings. These should be inspected for play or seized movements, as repair requires significant specialized labor.
• Steel Beam Corrosion: The cross-beams are made of galvanized mild steel. While robust, any breakdown in the galvanization can lead to internal rust, particularly where the beams meet the GRP hulls.
• Rudder Assembly: Historically, the rudder has been cited as a weak point in the design. Check for play in the stock and signs of stress around the transom mounting points.
• Osmosis: As with many early GRP builds from the 1970s, the hulls—especially the amas, which are often foam-filled—should be checked for osmotic blistering.

Community & Resources

The legacy of these boats is preserved by a dedicated group of enthusiasts. The Ocean Bird Trimaran Association remains the primary source for technical drawings, historical documentation, and advice on maintaining the folding wing mechanisms.

The Verdict

The Ocean Bird 30 is a cult classic that offers the stability of a multihull without the "berthing penalty." It is a testament to John Westell's engineering foresight and Honnor Marine's build quality.

Pros:

• Revolutionary folding beam allows for standard marina berthing.
• Extremely stable and safe for coastal and offshore cruising.
• Deep-cockpit and heavy displacement provide a secure feeling in rough seas.
• Shallow draft with daggerboard up allows for creek crawling.

Cons:

• Maintenance of the folding mechanism and steel beams is critical and can be costly.
• Heavier and slower than modern, lightweight trimarans.
• Interior volume is limited compared to catamarans of the same length.