Gulfstar 50 Kth Information, Review, Specs

Sailing Performance & Handling

The Gulfstar 50 Kth is characterized by its heavy displacement and a relatively high ballast-to-displacement ratio, which imparts a feeling of immense stability and "sea-kindliness." With a displacement of approximately 35,000 to 38,000 pounds, the boat is not a light-air performer; however, once the wind rises above 12 knots, the hull finds its stride. The ketch rig is particularly advantageous for short-handed crews; by "reefing from the ends"—dropping the mainsail and sailing under jib and mizzen—the boat remains balanced and easy to steer even in heavy weather.

The hull features a fin keel and a skeg-hung rudder, a configuration that offers a superior balance between tracking and maneuverability compared to the full-keel designs of previous decades. According to archival technical assessments by Practical Sailor, the boat’s performance was a revelation for the brand, moving away from the under-canvassed designs of the early 70s toward a more powerful sail-to-displacement ratio. Owners frequently report that the boat "sails on its feet," resisting excessive heeling and providing a dry, secure ride in offshore conditions.

Interior Comfort & Variations

The interior of the Gulfstar 50 Kth was designed during an era when live-aboard comfort was becoming a primary driver for the American cruising market. The vessel was offered in two primary configurations: a two-cabin "Owner's Version" and a three-cabin layout often used for charter or larger families. Both versions utilize the center-cockpit design to create a voluminous "Great Cabin" aft, featuring a queen-sized berth, private head, and, in many cases, a dedicated navigation station or vanity.

The walkthrough from the main salon to the aft cabin is a hallmark of the model, typically housing a linear galley that provides excellent bracing for the cook while underway. Earlier models (pre-1978) often featured Formica surfaces and darker wood tones, whereas later iterations transitioned to more traditional teak joinery and improved cabinetry. The main salon is notably wide, benefiting from the boat’s nearly 14-foot beam, with a large U-shaped dinette that can accommodate six to eight guests. Headroom is excellent throughout, rarely dipping below 6'4", making it a preferred choice for taller sailors.

Known Issues & Buyer’s Checklist

Prospective buyers should approach a Gulfstar 50 Kth with a focus on its structural and mechanical age, as these vessels are now decades into their service lives.

• Fuel and Water Tanks: One of the most significant "gotchas" involves the original iron or steel fuel tanks. These were often foamed into place or installed before the deck was joined to the hull. Over time, they are prone to corrosion from the outside in. Replacing them often requires significant joinery work or cutting through the cabin sole.
• Deck Core Integrity: Like many fiberglass boats of this vintage, the Gulfstar 50 uses a balsa or plywood core in the decks. Inspection should focus on areas around stanchion bases, chainplates, and the windlass, where moisture ingress can lead to delamination and soft spots.
• Chainplate Inspection: The chainplates on the 50 are massive but can suffer from crevice corrosion where they pass through the deck. A thorough survey should include pulling at least one or two for a visual inspection of the metal's condition hidden within the deck sandwich.
• Ballast Material: In some earlier hulls, Gulfstar used a concrete and iron slurry for ballast. While generally stable, if the fiberglass envelope around the ballast is breached, the iron can expand as it oxidizes, leading to "weeping" or cracks in the keel stub.
• Rudder Post and Skeg: The skeg-hung rudder should be checked for play in the bearings and signs of "wicking" moisture into the rudder blade itself, which can lead to internal structural degradation.

Community & Resources

The Gulfstar 50 enjoys a dedicated following, supported by the Gulfstar Owners Association, which maintains a repository of technical manuals, wiring diagrams, and historical brochures. Because so many of these vessels were used for circumnavigation, there is a wealth of "tribal knowledge" regarding offshore modifications and engine repowering (many original units were Perkins 4-236 or 6-354 diesels).

The Verdict

The Gulfstar 50 Kth remains one of the best values on the used market for sailors seeking a true "blue water" home. It successfully shed the builder's early reputation for mediocre performance, replacing it with a legacy of offshore reliability and immense interior volume.

Pros:

• Exceptional Liveability: The aft "Great Cabin" and wide salon provide comfort levels comparable to modern 55-footers.
• Rig Versatility: The ketch sail plan allows for easy sail reduction and balance in varying wind conditions.
• Solid Construction: Built during an era of heavy fiberglass layups, the hull is famously robust.
• Value: Offers significantly more interior space and offshore capability per dollar than many European counterparts of the same era.

Cons:

• Tankage Replacement: The difficulty of replacing original metal tanks is a major maintenance hurdle.
• Aesthetic Aging: Early models with heavy Formica use can feel dated without significant cosmetic overhauls.
• Light Air Performance: The heavy displacement hull requires a breeze to get moving, often necessitating engine use in light coastal winds.