Dufour 4800 Shoal draft

Sailboat specifications

The Dufour 4800 is a 34’11” (10.65m) cruising sailboat designed by Valentijn Design (Netherlands) and Michel Dufour (France). She was built between 1981 and 1985 by Dufour (France). The Shoal draft version features a shorter keel to grant access to shallow areas.

The Dufour 4800 is as well listed, on Boat-Specs.com, in Deep draft version (see all the versions compared).

Dufour 4800's main features

Model: Dufour 4800
Version: Shoal draft
Hull type: Monohull
Category: Cruising sailboat
Sailboat builder: Dufour
Sailboat designer: Valentijn Design & Michel Dufour
Country: France
Construction: GRP (glass reinforced polyester):
- Hull: Single skin fiberglass polyester
- Deck: Sandwich balsa fiberglass polyester
Number of hulls built: About 250
First built hull: 1981
Last built hull: 1985
Appendages: Keel : fin without bulb
Helm: Single tiller (helm wheel in option)
Rudder: Single semi-spade rudder
Unsinkable: No
Trailerable: No
Former French navigation category: 1
Standard public price ex. VAT (indicative only): N/A €

Dufour 4800's main dimensions

Hull length: 34’ 11”10.65 m
Waterline length: 27’ 7”8.4 m
Beam (width): 11’ 2”3.4 m
Draft: 4’ 11”1.5 m
Mast height from D_WL: 45’ 11”14 m
Light displacement (M_LC): 10582 lb4800 kg
Ballast weight: 5181 lb2350 kg
Ballast type: Cast iron
French customs tonnage: 9.99 Tx

Dufour 4800's rig and sails

Upwind sail area: 700 ft²65 m²
Downwind sail area: 1227 ft²114 m²
Mainsail area: 215 ft²20 m²
Genoa area: 484 ft²45 m²
Solent area: 334 ft²31 m²
Jib area: 172 ft²16 m²
Stormjib area: 75 ft²7 m²
Symmetric spinnaker area: 1012 ft²94 m²
I iFore triangle height (from mast foot to fore stay top attachment): 42’ 8”13 m
J iFore triangle base (from mast foot to bottom of forestay): 14’ 7”4.44 m
P iMainsail hoist measurement (from tack to head): 36’ 8”11.2 m
E iMainsail foot measurement (from tack to clew): 10’ 6”3.2 m
Rigging type: Sloop Marconi masthead
Mast configuration: Deck stepped mast
Rotating spars: No
Number of levels of spreaders: 1
Spreaders angle: 0 °
Spars construction: Aluminum spars
Standing rigging: 1x19 strand wire continuous

Dufour 4800's performances

HN (French rating) iHN or "Handicap Nationale" is an empirical rating system used in France allowing various monohulls, of different sizes and designs, to race each other fairly. It is particularly suitable for cruiser and cruiser-racer. Therefore, by comparing these values, we can have an indication of the relative speed of 2 boats.: 17.5
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.: 246 ft²/T22.84 m²/T
Downwind 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.: 431 ft²/T40.06 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.: 229
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.: 49 %
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.: 7.03 knots