Mamba Boats 311
Masthead Sloop · Fin keel, spade rudder · 1983–1986
A Bengt Karlsson-designed masthead sloop with a 45% ballast ratio, built as the performance-oriented successor to the 31
Designed by Bengt Karlsson.
- LOA
- Beam
- Draft (max)
- Displacement
- Ballast
- Hull type
- Fin w/spade Rudder
Is it for you?
Character
Where this design lands on the numbers a shopper trusts — read straight from her own ratios.
Her moderate displacement on a moderate beam gives 20 — a quick, lively motion that feels every wave.
2.04 — right around the 2.0 line, the edge between coastal and offshore.
190 — moderately heavy for her waterline, a balanced cruising weight.
15.6 — moderate power for her weight; steady, all-round performance.
46% of her weight is ballast — stiff, standing up well to her sails.
A balanced, easily-driven cruiser — comfortable and forgiving for coastal work.
The record
Full specifications
The complete reference set — tap any figure to switch between metric and imperial.
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.
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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