Island Packet 31 Information, Review, Specs

Sailing Performance & Handling

The Island Packet 31 is a heavy-displacement cruiser that prioritizes stability and tracking over raw speed. Its Displacement to Length (D/L) ratio of approximately 338 confirms its status as a robust "tank" of the sea, while its Sail Area to Displacement (SA/D) ratio of roughly 15.6 suggests it requires a moderate breeze to reach hull speed. Central to its handling is the signature Full Foil Keel, which integrates the ballast into a long, shallow-draft foil. This design provides excellent directional stability, allowing the boat to hold a course with minimal helm correction, even in confused seas.

In terms of rigging, most IP 31s were delivered as cutters, featuring a staysail and a furling genoa. This configuration allows for various sail combinations, making it easy to depower the yacht in heavy weather without sacrificing balance. Owners often report that while the boat does not point as high as a modern fin-keel racer—typically tacking through 100 to 110 degrees—it excels on a reach or a run. The rack-and-pinion steering system, a staple of early Island Packets, provides a mechanical, connected feel that is notably more durable than cable-based systems.

Interior Comfort & Variations

The interior of the Island Packet 31 is frequently cited as its most impressive feature, offering a level of livability rarely found in a 31-foot hull. Boasting a headroom of 6'3", the layout is centered around a massive main saloon that utilizes the boat’s 11'6" beam. The craftsmanship involves extensive use of teak and high-pressure laminates, creating a warm, traditional aesthetic. According to technical documentation from the Island Packet Yacht Owners Association, the layout includes a large V-berth forward, a drop-down table in the saloon that converts to a double berth, and a unique "quarter-cabin" aft that provides more privacy than a standard quarter berth.

A notable variation in this model line is the transition from the IP 31 to its successor, the Island Packet 32. While the hull remained largely similar, the 32 introduced an integrated swim platform and a slightly altered stern section. The IP 31 itself remained remarkably consistent throughout its production run, though late-model hulls (1988–1989) often featured updated portlights and refined interior cabinetry. The galley is U-shaped and positioned at the base of the companionway, providing security for the cook while underway—a hallmark of Bob Johnson’s offshore-centric design philosophy.

Known Issues & Buyer’s Checklist

Prospective buyers of an Island Packet 31 should focus on three primary areas that are common to the era and the brand's specific construction methods.

1. Chainplate Corrosion: Like many older Island Packets, the 31 uses 304-grade stainless steel chainplates encapsulated in fiberglass. Over decades, moisture can become trapped against the steel, leading to crevice corrosion. Because they are glassed-in, inspection is difficult and replacement is a major labor-intensive project.
2. Aluminum Tankage: The original fuel and holding tanks were constructed of aluminum and placed deep in the bilge or under the cabin sole. If moisture or acidic waste has sat in these tanks for decades, pinhole leaks are common. Replacing the fuel tank often requires cutting out a section of the cabin sole, which is a significant "gotcha" for second-hand buyers.
3. Deck Core Moisture: While the hull is solid fiberglass, the decks are cored with synthetics or wood in some areas. Check for "soft spots" around the stanchion bases and the staysail track, where hardware bedding may have failed over time.
4. Propeller Shaft Alignment: Due to the long keel design and the specific angle of the shaft log, ensuring the engine remains aligned is critical to preventing excessive vibration and cutlass bearing wear.

Community & Resources

The Island Packet community is one of the most organized and technically proficient in the sailing world. The Island Packet Yacht Owners Association (IPYOA) serves as the primary technical hub, offering a vast library of owner-contributed manuals, modification guides, and replacement part sources. Another prominent resource is IP Home Port, a long-standing volunteer-run site that hosts extensive forums and technical wikis dedicated to maintaining the legacy of these Florida-built cruisers.

The Verdict

The Island Packet 31 is a quintessential "slow but steady" cruiser that offers an extraordinary amount of interior space and safety for its size. It is an ideal choice for a couple or small family looking to transition from coastal hopping to blue-water voyaging without the expense of a 40-foot yacht.

Pros:

• Exceptional interior volume and headroom for a 31-foot boat.
• Highly stable and predictable "Full Foil Keel" design.
• Cutter rig offers versatile sail plans for heavy weather.
• Extremely robust construction with a solid fiberglass hull.

Cons:

• Difficult and expensive chainplate and tank replacements.
• Sluggish performance in light winds (under 10 knots).
• Limited pointing ability compared to modern fin-keel designs.
• The rack-and-pinion steering lacks the "light touch" desired by some sailors.