J/11S

Sailboat specifications

The J/11S is a 35’10” (10.9m) cruiser-racer sailboat designed by Alan Johnstone (United States). She was built between 2016 and 2019 by J/Boats (United States).

J/11S's main features

Model: J/11S
Hull type: Monohull
Category: Cruiser-racer sailboat
Sailboat builder: J/Boats
Sailboat designer: Alan Johnstone
Country: United States
Construction: GRP (glass reinforced polyester):
Sandwich fiberglass polyester
First built hull: 2016
Last built hull: 2019
Appendages: Keel : fin with bulb
Helm: Single tiller
Rudder: Twin spade rudders
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): About
165 000 €
(2017)

J/11S's main dimensions

Hull length: 35’ 10”10.9 m
Waterline length: 32’ 11”10.04 m
Beam (width): 10’ 11”3.31 m
Draft: 7’ 2”2.2 m
Light displacement (M_LC): 10141 lb4600 kg
Ballast weight: 3461 lb1570 kg

J/11S's rig and sails

Upwind sail area: 678 ft²63 m²
Downwind sail area: 1023 ft²95 m²
Symmetric spinnaker area: 1023 ft²95 m²
Rigging type: Sloop Marconi 9/10
Mast configuration: Keel stepped mast
Rotating spars: No
Number of levels of spreaders: 2
Spreaders angle: Swept-back
Spars construction: Aluminum spars
Standing rigging: Dyform

J/11S'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.: 245 ft²/T22.78 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.: 370 ft²/T34.35 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.: 129
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.: 34 %
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.: 7.69 knots