Allied Seawind Sailboat Review, Specs, and Listings

Thomas Gillmer·1962 – 1982·~161 hulls·Allied Boat Company Inc.
Allied Seawind drawingBuilder drawing
Hull Type
Monohull · long
Rig
Ketch
LOA
30.5' · 9.3 m
Disp.
12,000 lbs · 5,443 kg
First year
1962

The Allied Seawind 30 is a longkeeled ketch designed by Thomas Gillmer and built in the United States by the Allied Boat Company Inc. from 1962 through 1982. As the builder's first model, it set the tone for a marque favoring conservative fiberglass cruisers. With 161 hulls built, it remains a recognizable small bluewater ketch.

Measurements

Dimensions 01

Length Overall
30.5 ft
Length on deck
Waterline Length
24 ft
Beam
9.25 ft
Draft
4.5 ft
Maximum Headroom
Air Draft
44 ft

Construction & hull 02

Construction
Fiberglass
Hull Type
Monohull
Keel Type
Long
Rudder
1× Transom-Hung
Ballast
4,200 lbs (Lead)
Displacement
12,000 lbs
Water Capacity
30 gal
Fuel Capacity

Rig & sails 03

Rigging Type
Ketch
Mainsail luff
31.83 ft
Mainsail foot
13 ft
Foretriangle height
35.58 ft
Foretriangle base
12.25 ft
Forestay Length (estimated)
37.63 ft
Sail Area
502 sqft

Calculations 04

Sail Area to Displacement Ratio
15.32
Ballast to Displacement Ratio
35
Displacement to Length Ratio
387.52
Comfort Ratio
36.91
Capsize Screening Ratio
1.62
Hull Speed
6.56 kn

Design and Construction

Gillmer's Seawind carries a long keel with a transom-hung rudder, trading tight-quarter agility for directional stability. The hull is solid hand-laid fiberglass with extra-thick laminates in the bilge. Lead ballast is encapsulated in the keel layup and glassed over, bypassing external keel bolts. The hull-to-deck joint uses outward-turned flanges through-bolted on five-inch centers with sealant, glassed inside, and capped by an aluminum rubrail. Bulkheads tab directly to the hull. Decks use a balsa core.

Rig and Handling

The original Seawind was primarily a ketch. The foretriangle is 217.93 sq ft on a 35'7" hoist and 12'3" base; mainsail 206.90 sq ft; mizzen 85.76 sq ft. Sail-area/displacement is 15.38, displacement/length 387.52, ballast/displacement 34.0%, capsize screening 1.62, comfort 36.91—a heavy, stiff cruiser not built for speed.

Accommodations

Pre-1979 boats have woodgrain Formica veneer; later ones carry natural wood finishes. Build year predicts the trim.

Known Issues

The balsa-cored deck is the principal vulnerability: leaks at through-deck fittings rot the core from inside with little surface sign. Encapsulated ballast means keel-impact repair requires cutting into the laminate rather than withdrawing bolts.

Refits and Ownership

Later boats gained natural-wood interiors without structural change. The twenty-year span yields same lines, differing only in trim era.

The Verdict

A conservative ketch prioritizing ballast security over pace; balsa deck is the caveat.

Pros

  • Encapsulated lead ballast, no external bolts
  • Robust hull laminate in bilge
  • Long-keel directional stability
  • Clear early/late interior distinction

Cons

  • Balsa deck rot if fittings leak
  • Keel repair needs laminate cutting

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