|Hallberg-Rassy 31 MkI's Main Features|
|Model||Hallberg-Rassy 31 MkI|
|Type of hull||Monohull|
monolithic fiberglass / polyester
sandwich balsa / fiberglass / polyester
|First built hull||1992|
|Last built hull||2006|
|Number of hulls built||307|
Fin with bulb
|Rudder||1 spade rudder|
|Cockpit||Closed aft cockpit|
|Standard public price ex. VAT (indicative only)||N/A|
|Hallberg-Rassy 31 MkI's Main dimensions|
|Hull length||31’ 7”|
|Waterline length||27’ 1”|
|Beam (width)||10’ 10”|
|Light displacement||9921 lbs|
|Ballast weight||4409 lbs|
|Hallberg-Rassy 31 MkI's Rig and sails|
|Upwind sail area||491 sq.ft|
|Mainsail area||272 sq.ft|
|Jib area||219 sq.ft|
|Rigging type||Sloop Marconi 7/8|
|Mast position||Keel stepped mast|
|Spars||Mast and boom in Aluminum|
|Number of levels of spreaders||1|
|Hallberg-Rassy 31 MkI's Performances|
|Upwind sail area to displacementiThe 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 23 it indicates a fast sailboat.
|Displacement-Length ratio (DLR)iThe Displacement Length ratio is a figure that points out the boat's weight compared to its waterline length. 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.
|Ballast ratioiThe Ballast ratio is an indicator of the stability; it is obtained by dividing the boat's displacement by the weight of the ballast. Since the stability depends also of the hull shape and the position of the center of gravity, only boats with similar ballast arrangements and hull shape should be considered.
Higher the ballast ratio is, greater is the stability.
|Hull speediAs 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.
|Hallberg-Rassy 31 MkI's Auxiliary engine|
|Engine type||Inboard engine|
|Fuel tank capacity||15.9 gal|
|Hallberg-Rassy 31 MkI's Accommodation|
|Berth(s) (min/max)||4 / 6|
|Fresh water tank capacity||50.2 gal|
|Water heater capacity||5.8 gal|
|Hallberg-Rassy 31 MkI's Fore cabin|
|Hallberg-Rassy 31 MkI's Aft cabin|
|Berth length||7’ 5”|
|Berth width||5’ 4”|