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Performance & Speed

San Juan 77 Performance

How the San Juan 77 performs on the water — racing handicap, speed, sail-carrying power, stability and comfort.

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The San Juan 77 is aggressively canvassed for its weight, with a quick, snappy motion best suited to day sailing.

Hull Speed

The theoretical displacement-mode speed limit — determined by waterline length, not engine or sail power.

6.0 kts
A displacement hull pushes a bow wave whose speed is limited by the waterline length. With a waterline of 20.0′, the San Juan 77 tops out around 6.0 knots in displacement mode — after that, the bow wave outruns the hull and resistance climbs steeply.
1.34 × √20.0′ LWL = 6.0 kts

Performance Ratios

Racing handicap, sail-carrying power, stability and comfort — and what each one actually tells you about a day on the water.

SA / Displacement
22.5
Performance-oriented — carries a lot of canvas for its weight.
Comfort Ratio
11.4
Quick, snappy motion — better for day sails and racing than long passages.
Capsize Screening
2.58
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Hull Speed
6.0kts
S# (Speed Number)
3.6
Pounds/Inch Immersion
679lbs
Weight needed to sink the hull one inch — loading sensitivity.

Motion & Offshore Suitability

Two ratios that matter most when you're planning passages — how the boat feels in a seaway, and whether the hull geometry is suitable for open ocean.

Comfort Ratio
11.4
Quick, snappy motion — better for day sails and racing than long passages.
Under 20 — Snappy, racing motion
20–30 — Acceptable coastal
30–40 — Good offshore comfort
Over 40 — Very comfortable offshore
Capsize Screening Formula
2.58
Above the 2.0 offshore threshold — best suited for coastal and protected waters.
Under 2.0 — Acceptable for offshore
Over 2.0 — Coastal / protected waters

PHRF Fleet Position

Where the San Juan 77 sits on the PHRF handicap spectrum — lower numbers mean faster boats.

Cruiser 150–210
Heavy Cruiser 210–300
Islander 26 233s/nm
Ericson 26 2 234s/nm
Oday 26 237s/nm
Seafarer 26 237s/nm

Estimated Speed by Wind

Rough boat speed estimates at different true wind speeds and points of sail — derived from hull speed, SA/D, and displacement, not measured polars.

Point of Sail 6 kts TWS 10 kts TWS 15 kts TWS 20 kts TWS
Close-hauled40–50° 2.8 3.5 3.9 4.1
Close Reach60° 3.3 4.2 4.7 4.9
Beam Reach90° 4.1 5.2 5.8 6.0
Broad Reach120–135° 3.8 4.8 5.3 5.6
Run150–180° 3.0 3.8 4.3 4.5
These are simplified estimates based on hull speed (6.0 kts), SA/D (22.5), and empirical efficiency curves — not instrument-measured polars. Real-world speed varies with sea state, bottom condition, sail trim, and current. Speeds in gold approach hull speed; bold gold means near or at hull speed.

Wind Range & Comfort Envelope

Estimated wind ranges for comfortable sailing on the San Juan 77 — based on sail area, ballast, and displacement characteristics.

Ghost
Sweet Spot
Reef
Heavy
0–5 kts 5–16 kts 16–24 kts 24+ kts
Ghosting
0–5 kts
Light air, motor-sailing likely. Need patience and a light genoa.
Sweet Spot
5–16 kts
Comfortable under full sail. Best speed-to-comfort ratio.
Time to Reef
16–24 kts
Time to shorten sail. Reef the main, swap to a working jib.
Heavy Weather
24+ kts
Storm conditions. Storm jib or bare poles. Seek shelter if coastal.

How It Compares

Side-by-side with the boats most often cross-shopped against the San Juan 77.

San Juan 77 Columbia T 26 Ericson 26 2 Islander 26 Oday 26 Seafarer 26
Dimensions
LOA 25.8 25.8 25.8 25.8 25.7 25.8
LWL 20.0 22.8 21.9 21.7 21.6 22.8
Beam 9.5 8.0 9.3 10.0 8.0 8.3
Displacement 3 4 5 4 4 4
Ballast 1 1 2 2 1 1
Sail Area 304 270 326 302 270
Performance
PHRF 234 233 237 237
SA/Disp 22.5 16.1 17.3 17.1 15.7
Bal/Disp 31.8 42.9 38.5 38.6
Comfort 11.4 18.1 18.2 15.0 18.1
Capsize 2.58 1.95 2.13 2.38 1.99
Hull Speed 6.0 6.4 6.3 6.2 6.4