First 30 JK Shoal draft

Sailboat specifications

The First 30 JK is a 31’2” (9.52m) cruiser-racer sailboat designed by Juan Yacht Design (Spain). She was built between 2010 and 2015 by Bénéteau (France). The Shoal draft version features a shorter keel to grant access to shallow areas.

The First 30 JK is as well listed, on Boat-Specs.com, in Standard version (see all the versions compared).

First 30 JK's main features

Model: First 30 JK
Version: Shoal draft
Hull type: Monohull
Category: Cruiser-racer sailboat
Sailboat builder: Bénéteau
Sailboat designer: Juan Yacht Design
Sailboat range: First
Country: France
Construction: Hull and deck: GRP (glass reinforced polyester)
First built hull: 2010
Last built hull: 2015
Appendages: Keel : fin with bulb
Helm: Single tiller (helm wheel in option)
Rudder: Twin transom hung 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: B
Standard public price ex. VAT (indicative only): N/A €

First 30 JK's main dimensions

Overall length: 32’ 2”9.81 m
Hull length: 31’ 2”9.52 m
Waterline length: 27’ 6”8.39 m
Beam (width): 10’ 7”3.23 m
Draft: 4’ 11”1.5 m
Mast height from D_WL: 50’15.23 m
Light displacement (M_LC): 8267 lb3750 kg
Ballast weight: 2403 lb1090 kg
Ballast type: Cast iron

First 30 JK's rig and sails

Upwind sail area: 677 ft²62.91 m²
Downwind sail area: 1304 ft²121.11 m²
Mainsail area: 367 ft²34.11 m²
Genoa area: 310 ft²28.8 m²
Symmetric spinnaker area: 936 ft²87 m²
I iFore triangle height (from mast foot to fore stay top attachment): 41’ 8”12.7 m
J iFore triangle base (from mast foot to bottom of forestay): 13’ 8”4.19 m
P iMainsail hoist measurement (from tack to head): 40’ 5”12.3 m
E iMainsail foot measurement (from tack to clew): 14’ 5”4.4 m
Rigging type: Sloop Marconi 9/10
Mast configuration: Deck stepped mast
Rotating spars: No
Number of levels of spreaders: 2
Spreaders angle: Swept-back
Spars construction: Aluminum spars (carbon fiber spars as an option)
Standing rigging: 1x19 strand wire

First 30 JK'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.: 281 ft²/T26.06 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.: 540 ft²/T50.18 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.: 180
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.: 29 %
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