Hallberg-Rassy 31 MkI

Sailboat specifications

The Hallberg-Rassy 31 MkI is a 31’7” (9.62m) cruising sailboat designed by Frers Naval Architecture & Engineering (Argentina). She was built between 1992 and 2005 by Hallberg-Rassy (Sweden) with 306 hulls completed.

Hallberg-Rassy 31 MkI's main features

Model: Hallberg-Rassy 31 MkI
Hull type: Monohull
Category: Cruising sailboat
Sailboat builder: Hallberg-Rassy
Sailboat designer: Frers Naval Architecture & Engineering
Country: Sweden
Construction: GRP (glass reinforced polyester):
- Hull: Single skin fiberglass polyester
- Deck: Sandwich balsa fiberglass polyester
Number of hulls built: 306
First built hull: 1992
Last built hull: 2005
Appendages: Keel : fin with bulb
Helm: Single tiller
Rudder: Single spade rudder
Unsinkable: No
Trailerable: No
EC design category iThe CE design category indicates the ability to cope with certain weather conditions (the sailboat is designed for these conditions) A: Wind < force 9, Waves < 10m B: Wind < force 8, Waves < 8m C: Wind < force 6, Waves < 4m D: Wind < force 4, Waves < 0,5m: A
Standard public price ex. VAT (indicative only): N/A €

Hallberg-Rassy 31 MkI's main dimensions

Hull length: 31’ 7”9.62 m
Waterline length: 27’ 1”8.26 m
Beam (width): 10’ 10”3.3 m
Draft: 5’ 7”1.71 m
Light displacement (M_LC): 9921 lb4500 kg
Ballast weight: 4409 lb2000 kg
Ballast type: Lead on deep GRP bilge

Hallberg-Rassy 31 MkI's rig and sails

Upwind sail area: 491 ft²45.6 m²
Mainsail area: 272 ft²25.3 m²
Jib area: 219 ft²20.3 m²
Rigging type: Sloop Marconi 7/8
Mast configuration: Keel stepped mast
Rotating spars: No
Number of levels of spreaders: 1
Spreaders angle: Swept-back
Spars construction: Aluminum spars
Standing rigging: Continuous

Hallberg-Rassy 31 MkI's performances

Upwind sail area to displacement iThe ratio sail area to displacement is obtained by dividing the sail area by the boat's displaced volume to the power two-thirds. The ratio sail area to displacement can be used to compare the relative sail plan of different sailboats no matter what their size. Upwind: under 18 the ratio indicates a cruise oriented sailboat with limited performances especially in light wind, while over 25 it indicates a fast sailboat.: 180 ft²/T16.73 m²/T
Displacement-length ratio (DLR) iThe Displacement Length Ratio (DLR) is a figure that points out the boat's weight compared to its waterline length. The DLR is obtained by dividing the boat's displacement in tons by the cube of one one-hundredth of the waterline length (in feet). The DLR can be used to compare the relative mass of different sailboats no matter what their length: a DLR less than 180 is indicative of a really light sailboat (race boat made for planning), while a DLR greater than 300 is indicative of a heavy cruising sailboat.: 226
Ballast ratio iThe Ballast ratio is an indicator of stability; it is obtained by dividing the boat's displacement by the mass of the ballast. Since the stability depends also of the hull shapes and the position of the center of gravity, only the boats with similar ballast arrangements and hull shapes should be compared. The higher the ballast ratio is, the greater is the stability.: 44 %
Critical hull speed iAs a ship moves in the water, it creates standing waves that oppose its movement. This effect increases dramatically the resistance when the boat reaches a speed-length ratio (speed-length ratio is the ratio between the speed in knots and the square root of the waterline length in feet) of about 1.2 (corresponding to a Froude Number of 0.35) . This very sharp rise in resistance, between speed-length ratio of 1.2 to 1.5, is insurmountable for heavy sailboats and so becomes an apparent barrier. This leads to the concept of "hull speed". The hull speed is obtained by multiplying the square root of the waterline length (in feet) by 1.34.: 6.98 knots