BoatsCape Cod Shipbuilding Mercury 15 FK

Cape Cod Shipbuilding Mercury 15 FK

Fractional Sloop · Fin w/transom Hung Rudder · First built 1940

A 1940 Sparkman & Stephens design featuring a fin keel and high sail-area-to-displacement ratio for nimble sailing

Designed by Sparkman & Stephens.

LOA
Beam
Draft (max)
Displacement
Ballast
Hull type
Fin w/transom Hung Rudder

Is it for you?

Character

Where this design lands on the numbers a shopper trusts — read straight from her own ratios.

TrailerableBeam 1.65 m — inside the 2.55 m no-permit tow width across most of Europe, and the 2.59 m US and Canadian limit. About 331 kg of hull, so roughly 950 kg on a trailer: check that against your own towing rating.Ramp-launchableAbout 331 kg of hull, with a keel that raises or a draught shallow enough to float off a trailer — she can go back on the trailer at the ramp, not only into the water.Shoal draughtDraws 0.74 m, board up where she has one — creeks, sandbars and thin anchorages most keels have to stay out of.
LivelySea-kindly

Her light displacement on a beamy beam gives 8 — a quick, lively motion that feels every wave.

Comfort ratio 8
CoastalBluewater

At 2.41 she sits above the 2.0 line — beamy for her weight, and happiest coastal.

Capsize screening 2.41
LightHeavy

123 — light for her waterline, so she is easily driven and quick to accelerate.

Displacement / length 123
EasygoingPowered-up

23.5 — a lot of sail for her weight; powered-up and eager, a real performer.

Sail area / displacement 23.5
TenderStiff

41% of her weight is ballast — moderately stiff, a middle-of-the-road stability.

Ballast 41%

Light and lively — happiest day-sailing and coastal-hopping in settled weather.

  • Lighter than ~79% of boats her size on file
  • Narrower than ~97% of boats her size on file

Compared with 73 boats of the same type within a quarter of her length.

The record

Full specifications

The complete reference set — tap any figure to switch between metric and imperial.

Dimensions
Weights
Ballast / displacement
41.1%
Rig & sail area
Rig
Fractional Sloop
Ratios
SA / displacement
23.5
Displacement / length
123.2
Comfort ratio
8.4
Capsize screening
2.41
Hull speed
5.0 kn
Pounds / inch immersion
268
Hull
Hull type
Fin w/transom hung rudder
Construction
Wood
Ballast type
Iron
Production
Years built
First built 1940
Designer
Sparkman, Stephens
Builder
Cape Cod Shipbuilding

Boats like this, on the water

Nobody has filmed this one — but these are close.

Comparable boats the fleet has on camera: same type, within a quarter of her length. Open the boat, or watch the video — a timestamp means she only appears in passing.

Birdyfish S4.20 mSame hull family0.4 m shorterA 4.2-metre foiling monohull with a 100kg displacement and a high-performance Marconi cat rig
Can a Normal Sailor Actually Buy a Foiling Dinghy Now?2:23from Practical Sailor

The family

Boats like this

Nearby designs by size, type, and era — worth a look alongside her.

Cape Cod Shipbuilding Mercury 15 CBA Sparkman & Stephens fractional sloop and early fiberglass pioneer designed for nimble performance in a 15-foot hullMercury 18A pioneering one-design plywood sloop from 1939 that remains a lively, high-performance racer todayCape Cod CatA gaff-rigged catboat by Charles Wittholz featuring a keel-centerboard configuration for versatile shoal-draft sailingCape Cod Shipbuilding GeminiA 1955 A. Sidney DeWolf Herreshoff design featuring unique twin side-by-side centerboards for shallow-water versatility

Keep looking

Nothing filmed of this one yet

Two ways to keep looking — both search what the fleet has actually recorded.

Search the fleet for boats like thisAsk the fleet about the Cape Cod Shipbuilding Mercury 15 FK

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