BoatsLm 23

Lm 23

Masthead Sloop · Long Keel · 1969–1975

A Palle Mortensen-designed masthead sloop with a long keel, built from 1969 to 1975 for steady coastal cruising

Designed by Palle Mortensen.

LOA
Beam
Draft (max)
Displacement
Ballast
Hull type
Long Keel

Is it for you?

Character

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

TrailerableBeam 2.40 m — inside the 2.55 m no-permit tow width across most of Europe, and the 2.59 m US and Canadian limit. About 2,000 kg of hull, so roughly 2,600 kg on a trailer: check that against your own towing rating.Shoal draughtDraws 0.90 m, board up where she has one — creeks, sandbars and thin anchorages most keels have to stay out of.
LivelySea-kindly

Her moderate displacement on a moderate beam gives 20 — a moderate, middle-of-the-road motion.

Comfort ratio 20
CoastalBluewater

1.92 — just under the 2.0 offshore line; her beam is modest for her weight.

Capsize screening 1.92
LightHeavy

228 — moderately heavy for her waterline, a balanced cruising weight.

Displacement / length 228
EasygoingPowered-up

14.7 — modest power for her weight; easygoing rather than lively, and happier with a breeze.

Sail area / displacement 14.7
TenderStiff

40% of her weight is ballast — moderately stiff, a middle-of-the-road stability.

Ballast 40%

A capable cruiser that sits just inside the offshore line — coastal work with real passages in her.

  • Draws less than ~80% of boats her size on file

Compared with 189 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
40.0%
Rig & sail area
Rig
Masthead Sloop
Ratios
SA / displacement
14.7
Displacement / length
228.1
Comfort ratio
20.4
Capsize screening
1.92
Hull speed
6.1 kn
Pounds / inch immersion
577
Hull
Hull type
Long Keel
Construction
Fiberglass
Production
Years built
1969–1975
Units built
670
Designer
Palle Mortensen
Builder
LM Glasfiber A, S

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.

Greenwich 247.39 mSame hull family0.3 m longerA George H. Stadel Jr. long-keeled masthead sloop that served as the direct predecessor to the Cape Dory 25
Contessa 267.77 mSame hull family0.7 m longerA David Sadler-designed long-keel masthead sloop, built in both England and Canada with a 25-year production run
Pearson Yachts Ensign6.86 mSame hull family0.2 m shorterA Carl Alberg-designed fractional day sailor and one-design racer built on the proven Electra hull for active club fleets
Island Packet 278.08 mSame hull family1.0 m longerA Robert K. Johnson-designed cutter with a long keel, built for stability and comfort in a compact 8-meter package
Pearson Yachts-USA Triton8.63 mSame hull family1.5 m longerA Carl Alberg-designed long-keel fractional sloop that pioneered fibreglass cruising and saw international production.
Flicka 207.32 mSame hull family0.2 m longerA Bruce Bingham-designed cutter with a long keel, originally offered as amateur plans before becoming a production classic

The family

Boats like this

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

Keep looking

Nothing filmed of this one yet

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

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