FORGUS 31
Specifications
Hull
| LOA | 30.51 ft |
| LWL | 24.28 ft |
| Beam | 10.5 ft |
| Draft | 5.38 ft |
| Displacement | 9,700 lb |
| Ballast | 4,408.7 lb |
| Hull speed1.34·√LWL | 6.6 kn |
Rig & Sails
| Iforetriangle height | 41.01 ft |
| Jforetriangle base | 12.47 ft |
| Pmainsail luff | 35.6 ft |
| Emainsail foot | 10.24 ft |
| FLforestay | 12.5 ft |
| Mainsail | 452.6 sq ft |
| Jib (100%) | 255.7 sq ft |
| Spinnaker | 434.7 sq ft |
About the FORGUS 31
Designed by Hugo Samuelsson and Lars Hedberg and built by Forgus Yachts (SWE) from 1973–1983, the Forgus 31 is a robust, heavy-displacement cruiser with a D/L ratio of 302.54 and a comfort ratio of 25.02. While the exact hull count is unknown, owner reports highlight its solid construction but warn of critical structural vulnerabilities in the deck core and mast step.
- Best for:
- This boat suits experienced coastal cruisers and those seeking a stable, heavy-weather platform who are prepared to manage significant maintenance on aging composite structures. It is less ideal for novice owners due to the high frequency of reported structural repairs.
- Bluewater capability:
- With a displacement of 9700.0 lb, a low capsize ratio of 1.97, and a fin keel, the Forgus 31 is inherently capable of offshore passage making, provided the critical structural integrity of the deck and keel is verified.
- Comparables:
- Comparable to other heavy Scandinavian designs from the 1970s such as the Hallberg-Rassy 31 or Nautor's Swan 36, sharing similar displacement characteristics and cruising-oriented hull forms. These boats offer similar stability and build quality but often command higher prices due to brand prestige.
Performance
ORC Performance Data(1 certificate)
Measured performance data from ORC (Offshore Racing Congress) certificates.
Polar Diagram
Boat speed (kn) vs. true wind angle. Source: ORC
Racing Ratings
Triple Number
ORC Measured
Sail Areas (ORC)
Speed Table (kn)
| TWA \ TWS | 6 | 8 | 10 | 12 | 14 | 16 | 20 |
|---|---|---|---|---|---|---|---|
| 52° | 4.4 | 5.2 | 5.8 | 6.2 | 6.4 | 6.5 | 6.6 |
| 60° | 4.7 | 5.5 | 6.1 | 6.4 | 6.6 | 6.7 | 6.8 |
| 75° | 5.0 | 5.8 | 6.3 | 6.5 | 6.7 | 6.9 | 7.2 |
| 90° | 4.9 | 5.8 | 6.3 | 6.6 | 6.8 | 6.9 | 7.3 |
| 110° | 4.9 | 5.9 | 6.4 | 6.7 | 7.0 | 7.3 | 7.6 |
| 120° | 4.8 | 5.7 | 6.3 | 6.7 | 7.0 | 7.3 | 7.8 |
| 135° | 4.4 | 5.3 | 6.1 | 6.5 | 6.8 | 7.0 | 7.6 |
| 150° | 3.8 | 4.7 | 5.5 | 6.1 | 6.5 | 6.8 | 7.3 |
| Beat VMG | 2.9 | 3.4 | 3.8 | 4.2 | 4.4 | 4.5 | 4.6 |
| Run VMG | 3.3 | 4.1 | 4.8 | 5.4 | 6.0 | 6.4 | 6.9 |
Estimated Value
Limited DataEstimated Cost of Ownership
Based on 30.51ft LOA. Actual costs vary by condition, usage, and local rates.
Known Issues & Pre-Purchase Inspection
11 reported issues across 7 systems for the FORGUS 31, compiled from owner reports in sailing forums and owner-association material.
Unlock the full inspection report
Thinking of buying a FORGUS 31? This is an in-depth report on the faults this model is known for — so you know exactly what to check when you walk the boat. For the price of a coffee.
- ✓ All 11 specific issues — severity, symptoms & fixes
- ✓ Model-specific pre-purchase inspection checklist
- ✓ Downloadable PDF to take to your surveyor — yours to keep
One-time $2.99 · secure checkout by Stripe · instant access · 30 days online, PDF yours to keep
Similar Sailboats
Which engine powers your FORGUS 31?
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Brands sometimes mentioned for this model: Yanmar — is it one of these?
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Used sails that fit the FORGUS 31
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