Allied Seawind Mk II Ketch — Information, Review, Specs

Thomas Gillmer·1975 – 1982·~130 hulls·Allied Boat Company Inc.
Allied Seawind Mk II Ketch drawingBuilder drawing
Hull type
Monohull · full
Rig
Ketch
LOA
31.58' · 9.63 m
Displ.
14,900 lbs · 6,759 kg
First year
1975

The Allied Seawind II, often referred to as the Seawind Mark II, represents a significant evolution of the vessel that famously became the first fiberglass sailboat to circumnavigate the globe. Designed by Thomas Gillmer and introduced in 1975, the Seawind II was not merely a revision of the original 30foot Seawind but a completely new hull and deck design aimed at providing more interior volume and improved offshore stability. While the original Seawind was a compact 30 feet, the Mark II grew to nearly 32 feet with a substantially wider beam of 10 feet 5 inches, making it a much more formidable longdistance cruiser. Built with the heavyduty scantlings Allied was known for, the Seawind II was primarily produced as a ketch, though a cutterrigged version was also offered to sailors who preferred a simpler sail plan.

Measurements

Dimensions 01

Length overall
31.58 ft
Length on deck
Waterline length
25.5 ft
Beam
10.42 ft
Draft
4.5 ft
Maximum headroom
Air draft

Construction & hull 02

Construction
Fiberglass (Balsa Core)
Hull type
Monohull
Keel type
Full
Rudder
1× Attached
Ballast
5,400 lbs (Lead)
Displacement
14,900 lbs
Water capacity
60 gal
Fuel capacity
40 gal

Rig & sails 03

Rig type
Ketch
Mainsail luff
33.83 ft
Mainsail foot
12 ft
Foretriangle height
38.78 ft
Foretriangle base
13.75 ft
Forestay length (estimated)
41.15 ft
Sail area
555 sqft

Calculations 04

Sail area to displacement ratio
14.66
Ballast to displacement ratio
36.24
Displacement to length ratio
401.16
Comfort ratio
37.15
Capsize screening formula
1.69
Hull speed
6.77 kn

Sailing Performance & Handling

The Seawind II is widely regarded as a quintessential "heavy cruiser," characterized by a motion that is predictable and comfortable in a seaway. With a displacement of roughly 14,900 pounds and a ballast-to-displacement ratio approaching 40%, the boat is stiff and excels when the wind picks up. According to technical assessments by noted delivery skipper and author John Kretschmer in Cruising World, the boat’s full keel with a cutaway forefoot allows it to track exceptionally well, a trait highly prized by single-handed sailors and those crossing oceans.

The ketch rig provides a versatile "sail locker" for various weather conditions. In heavy air, the ability to sail under "jib and jigger" (headsail and mizzen) keeps the boat balanced and the center of effort low, reducing heel and helm fatigue. While its Displacement/Length ratio (well over 300) suggests it is not a light-air performer, the Seawind II maintains momentum through chop that would stop lighter boats. Handling under power is typical for a full-keeled vessel; while it requires a firm hand in tight marinas, the large rudder provides enough authority once some wash is moving over it.

Interior Comfort & Variations

Unlike its predecessor, which was criticized for its cramped quarters, the Seawind II offers a surprisingly voluminous interior for a 32-foot boat. The 10' 5" beam is carried well aft, allowing for a layout that features a genuine navigation station and a functional galley. The standard arrangement includes a V-berth forward, a head with a shower, and a main saloon with a pull-out double berth to port and a single settee to starboard. With over 6 feet of headroom, the cabin feels airy, a sensation bolstered by the extensive use of warm teak joinery.

The primary variation of this model is the rig. While the ketch is the most common and iconic version, Allied also produced a Seawind II Cutter. The cutter variant utilizes the same hull but trades the mizzen mast for a taller mainmast and a bowsprit, appealing to those who prioritize upwind performance and reduced rigging complexity. Regardless of the rig, the build quality remains consistent, with Allied using substantial fiberglass laminates and through-bolted deck hardware.

Known Issues & Buyer’s Checklist

Prospective buyers should approach a Seawind II with a focus on age-related structural maintenance common to 1970s fiberglass builds.

  • Deck Core Integrity: Like many boats of this era, the Seawind II utilizes a balsa-cored deck. Moisture ingress around stanchion bases, chainplates, or the mizzen mast step can lead to delamination. A percussion test (tapping with a plastic hammer) is essential to identify soft spots.
  • Chainplates: The stainless steel chainplates are robust, but the seals where they pass through the deck are prone to leaking. If left unaddressed, this moisture can migrate into the plywood bulkheads, leading to rot and structural compromise.
  • Fuel and Water Tanks: Many Seawind IIs were equipped with aluminum or black iron tanks. Over four decades, these can suffer from internal corrosion. Replacing the fuel tank, located under the cockpit sole, often requires significant labor or engine removal.
  • Osmotic Blistering: While Allied used high-quality resins, some hulls have shown tendencies toward osmotic blistering. A haul-out inspection is necessary to verify the hull's condition below the waterline.

Community & Resources

The Allied Seawind II benefits from a dedicated and highly active community of owners who value the brand’s "overbuilt" reputation. The Allied Boat Owners group is the primary hub for technical exchange, providing digitized original manuals and advice on refitting Thomas Gillmer’s designs. Because many of these boats have completed multiple Atlantic or Pacific crossings, the community is a wealth of knowledge regarding offshore modifications and heavy-weather tactics specific to the Seawind’s hull shape.

The Verdict

The Allied Seawind II Ketch is a definitive choice for the sailor who prioritizes safety and sea-kindliness over modern racing speeds. It is a "purpose-built" voyager that remains one of the most affordable ways to acquire a proven blue-water vessel.

Pros

  • Exceptional build quality and solid fiberglass hull construction.
  • Versatile ketch rig allows for excellent balance in heavy weather.
  • Spacious interior for its length, featuring high-quality teak craftsmanship.
  • Excellent tracking and a comfortable motion at sea.

Cons

  • Languid performance in light winds (under 8-10 knots).
  • Propensity for deck leaks and potential core rot if neglected.
  • Challenging to maneuver in reverse due to the full-keel design.

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