Cobra 35 Information, Review, Specs

Sailing Performance & Handling

Under sail, the Cobra 35 is characterized by a "steady and sedate" demeanor, though it possesses a surprising degree of stiffness thanks to its generous ballast-to-displacement ratio, which typically hovers around 40 percent. The hull features a fine entry that transitions into a massive 12-foot beam, providing significant form stability. Most units were produced with a masthead sloop rig, which provides a simple, manageable sail plan for short-handed crews.

The boat was offered in both fin keel and bilge keel (twin keel) configurations. The bilge keel version, which allowed the vessel to dry out in tidal estuaries—a necessity for many UK sailors—was particularly well-regarded for its ability to track decently to windward, a feat achieved by Feltham’s "splayed" keel design that increased effective depth when heeled. While not a light-air performer due to its moderate-to-heavy displacement of approximately 12,500 lbs, the Cobra 35 excels when the wind picks up. Owners frequently report that the vessel feels most at home in a Force 4 or 5, where its weight and hull shape provide a "sea-kindly" motion that minimizes slamming in choppy coastal waters.

Interior Comfort & Variations

The defining characteristic of the Cobra 35 is its cavernous interior, which utilized the boat’s 12-foot beam to its full potential. For a yacht designed in the late 1970s, the use of space was revolutionary. The layout typically features a private forward V-berth, a large U-shaped dinette to port that converts into a double berth, and a linear or L-shaped galley. One of the primary advantages of the 35 over its sibling, the Cobra 850, is the increased headroom—exceeding 6 feet in most of the salon—and the addition of a dedicated navigation station.

Variations in the interior are common, as many Cobras were sold as "owner-finished" kits. This means that while the hull and deck were professionally molded, the teak joinery and cabinetry can vary in quality from one vessel to another. High-end builds feature extensive teak louvred doors and solid wood trim, creating a warm, traditional atmosphere. Later iterations often incorporated an aft quarter-berth or a small aft cabin, though the primary focus remained on a spacious central living area that could comfortably sleep six to seven adults.

Known Issues & Buyer’s Checklist

Prospective buyers should approach a Cobra 35 with the diligence required for any GRP vessel of its age. Technical areas of concern include:

• Rudder Construction: Like many David Feltham designs of this period, the rudder features a stainless steel shaft with internal mild-steel "tangs" welded to it. Over time, water can seep into the rudder core, causing the tangs to corrode and potentially allowing the rudder to spin on its shaft. A thorough inspection for "slop" or weeping rust is essential.
• Headlining Failure: The original foam-backed vinyl headlining is a common failure point. The foam degrades into a fine powder, causing the vinyl to sag. Many owners have replaced this with wood slats or new panels, which is a labor-intensive but necessary upgrade.
• Osmosis: While Cobra hulls are known for a heavy layup, they were built before the widespread use of vinylester resins. Instances of osmotic blistering are not uncommon, though they are usually considered cosmetic rather than structural given the thickness of the laminate.
• Chain Plate Security: Check for water ingress around the chain plates. If leaks are left unaddressed, the plywood bulkheads to which the chain plates are bolted can rot, compromising the structural integrity of the rig.

Community & Resources

The primary hub for technical support and historical data is the Cobra and Seawolf Owners Association. This organization maintains a repository of David Feltham’s original design notes and facilitates communication between owners of the 700, 750, 850, and 1050/35 models. While the association is less active than larger brand clubs, it remains the definitive source for cross-referencing parts and rigging specifications unique to the Cobra line.

The Verdict

The Cobra 35 is an exceptional "bang-for-your-buck" cruiser that offers the internal volume of a modern 38-footer with the rugged durability of the early fiberglass era.

Pros:

• Remarkable interior volume and 12-foot beam.
• Highly stable and forgiving in heavy weather.
• Versatile keel options (bilge keel versions are ideal for tidal drying moorings).
• Robust GRP construction that inspires confidence in coastal passages.

Cons:

• Underpowered in light winds due to weight.
• Interior finish quality can vary based on the original "kit" builder.
• Prone to typical era-specific maintenance issues (headlining and rudder tangs).