Catana 42
catamaran · approved by seed
Performance & stability indicators
Calculated from the specifications below. Comparative aids only — not a stability assessment.
| SA/D — Sail area / displacement Power-to-weight ratio of the rig — the classic comparison ratio. Imperial: SA ft² ÷ (displacement lb ÷ 64)^⅔. Higher = more powerful for its weight. | 26.54 (12.61 m² per tonne) |
| BN — Bruce number Power-to-weight indicator of speed potential (√SA ft² ÷ displacement lb^⅓). Below ~1.3 is slow in light airs; ~1.6 reefs early offshore. | 1.29 (26.11 metric scale) |
| BSpd — Base speed Distance a boat could average over 24 hours, empirically derived (Richard Boehmer, 1989). Also used to handicap mixed-fleet races. | 10.8 kn (20.0 km/h) |
| KSP — Kelsall speed prediction Derek Kelsall's performance index (PI-C × 10), expressed in knots — an estimate of speed potential on a reach. A value of 8 ≈ 8 knots in a 10-knot wind. | 7.9 kn (14.6 km/h) |
| Texel — Texel rating (Multihull Dynamics) Multihull Dynamics simplified Texel approximation - matches the numbers they published. LOWER = faster. | 114.9 (lower = faster) |
| Texel* — Texel rating (official / global) The authoritative CTC / Watersportverbond Texel formula - the same core used by OMR (Australia) and Multi 2000 (France). Includes crew weight, so it sits on a higher numerical scale than the MD approximation (identical ordering). LOWER = faster. | 145.2 (lower = faster) |
| SSpd — Stability speed Wind speed (knots) at which the windward hull of a catamaran (or main hull of a trimaran) begins to lift — Shuttleworth, incl. a 40% gust factor. Higher = more stable. | 18.37 kn (34.0 km/h) |
| KSI — Kelsall stability indicator Indicator of resistance to sideways capsize (Derek Kelsall). Higher = more resistant. | 30.9 (34.0 km/h wind equiv.) |
Specifications
| Manufacturer | Catana |
| Model | 42 |
| Variant | — |
| Year from | — |
| Year to | — |
| Hull type | catamaran |
| Boat style | — |
| Construction | Composite |
| LOA (m) | 12.6 (41.34 ft) |
| Waterline length (m) | 12.37 (40.58 ft) |
| Beam overall (m) | 6.88 (22.57 ft) |
| Beam waterline (m) | — |
| Hull width (m) | 1.39 (4.56 ft) |
| Beam centreline (m) | 5.49 (18.01 ft) |
| Bridge deck clearance (m) | — |
| Draft min (m) | — |
| Draft max (m) | — |
| Board type | — |
| Displacement light (kg) | 8880 (19577.03 lb) |
| Displacement loaded (kg) | — |
| Sail area upwind (m²) | 111.95 (1205.02 ft²) |
| Sail area downwind (m²) | — |
| Total engine power (kW) | — |
| Number of engines | — |
| Fuel (L) | — |
| Water (L) | — |
| Berths | — |
| Headroom (m) | — |
| Notes | Performance cruising catamaran. |
| Sources | Multihull Dynamics vessel page (2021), via yachtsite.com: https://www.yachtsite.com/reference/catamaran-bridge-clearance-and-stability-multihull-dynamics-interview/ |
| approved_by | seed |
| approved_at | 2026-10-30 09:03:18 |
Official Texel* — propeller adjustment
Texel* above uses a propeller factor of 1 (retractable / unknown). Propellers are commonly swapped between otherwise identical boats, so pick a configuration here to compare like-for-like. No board type recorded — add one to apply the official no-board correction.
Texel* with propellers: —