Tanton Offshore 39 Information, Review, Specs

Sailing Performance & Handling

The defining characteristic of the Tanton Offshore 39 is its unstayed cat-ketch sail plan. Unlike a traditional sloop, the Offshore 39 utilizes two masts of nearly equal height, positioned well forward and aft. This configuration eliminates shrouds and stay wires, allowing the sails to rotate 360 degrees. According to technical archives from Tanton Yacht Design, this design philosophy focuses on reducing windage and simplifying sail handling. By spreading the sail area across two smaller mainsails rather than one large one, the center of effort remains low, reducing heeling moments and making the boat exceptionally stable in heavy weather.

The handling is described by owners as "surgical" compared to the heavier full-keeled cruisers of the era. With a fin keel and a skeg-hung rudder, the Offshore 39 maneuvers more like a modern performance cruiser than a traditional double-ender. Because there is no forestay, there is no headsail to tack; the helmsman simply turns the wheel, and the sails find their own way across the wind. This makes the boat a favorite for solo circumnavigators. However, sailors used to traditional rigs may find the "bendy" nature of the freestanding masts disconcerting at first, as they are designed to flex and spill air during gusts—a built-in safety mechanism that prevents over-powering.

Interior Comfort & Variations

Inside, the Tanton Offshore 39 benefits from Ta Chiao’s expertise in joinery but applies it to a more contemporary, open-concept layout. The absence of a traditional mast step in the center of the main salon (due to the mast placements being at the extreme ends of the cabin house) creates an unusually spacious and airy living area. The interior is typically finished in high-quality teak, though it lacks the dark, cramped feel of earlier Taiwanese builds.

The Offshore 39 was often customized, but the most common configuration includes a large V-berth forward, a wrap-around dinette, and a sea-friendly galley located near the companionway. A notable sibling model is the Offshore 37, which utilizes a similar hull form but with a slightly truncated stern. Some versions of the 39 were also built with a traditional sloop rig for buyers wary of the cat-ketch concept, though these are rare and lack the design's original balance. The "Mark II" variants often featured upgraded keel profiles and modified interior cabinetry to allow for more storage during long-range passages.

Known Issues & Buyer’s Checklist

Prospective buyers should approach the Tanton Offshore 39 with a focus on its unique structural requirements. The most critical area for inspection is the mast partners and the "bury" (the section of the mast below the deck). Because the masts are freestanding, the leverage exerted on the deck and the mast step is immense. Inspectors should look for stress cracking in the fiberglass around the partner area or any signs of moisture ingress in the deck core where the masts penetrate.

The original masts were often built by TPI (Tillotson-Pearson Inc.) using early carbon fiber technology. While robust, these should be professionally surveyed for UV degradation or hairline fractures. Additionally, because many of these vessels were built by Ta Chiao during a period where teak decks were standard, the condition of the deck fastening system is a common concern. If the teak is original, there is a high probability of "weeping" screws, which can lead to core saturation. Lastly, the plumbing and electrical systems on Taiwanese yachts of this vintage often require a total overhaul to meet modern ABYC standards, as the original wiring was frequently undersized.

Community & Resources

The Tanton Offshore 39 occupies a niche within the broader cruising community. The most reliable technical resource for the model remains the designer himself; Yves-Marie Tanton continues to maintain an active design office and is known to provide original sail plans and technical advice to current owners. While there is no dedicated "Offshore 39" association, owners are frequently active in the "Freestanding Rig" groups and general Ta Chiao owner associations, where they share data on refitting the unique carbon fiber spars.

The Verdict

The Tanton Offshore 39 is an intellectual’s cruising boat—a marriage of Taiwanese craftsmanship and French-American naval innovation. It is ideal for the sailor who prioritizes ease of handling and "line-of-sight" simplicity over the raw power of a cutter rig.

Pros:

• Exceptional ease of handling due to the stayless cat-ketch rig.
• Spacious interior layout unencumbered by central mast steps.
• High-quality Ta Chiao interior joinery.
• Strong tracking and sea-kindliness provided by the double-ended hull.

Cons:

• Freestanding masts require specialized surveys and can be difficult to replace.
• The absence of a headsail limits performance in very light winds.
• Potential for core issues if the original teak decks have not been maintained.