First 310 Deep draft

Sailboat specifications

The First 310 is a 30’ (9.14m) cruiser-racer sailboat designed by Finot Conq Architectes (France). She was built between 1990 and 1995 by Bénéteau (France) with 496 hulls completed. The Deep draft version offers a deeper L-shaped keel bringing extra performance especially upwind.

The First 310 is as well listed, on Boat-Specs.com, in Wing keel version (see all the versions compared).

First 310's main features

Model: First 310
Version: Deep draft
Hull type: Monohull
Category: Cruiser-racer sailboat
Sailboat builder: Bénéteau
Sailboat designer: Finot Conq Architectes
Sailboat range: First
Country: France
Construction: GRP (glass reinforced polyester):
- Hull: Single skin fiberglass polyester
- Deck: Sandwich balsa fiberglass polyester
Number of hulls built: 496
First built hull: 1990
Last built hull: 1995
Appendages: Keel : fin with bulb
Helm: Single tiller
Rudder: Single spade rudder
Unsinkable: No
Trailerable: No
Former French navigation category: 2
Standard public price ex. VAT (indicative only): N/A €

First 310's main dimensions

Overall length: 31’ 1”9.47 m
Hull length: 30’9.14 m
Waterline length: 28’ 10”8.79 m
Beam (width): 10’ 7”3.23 m
Waterline beam (width): 8’ 5”2.56 m
Draft: 6’1.83 m
Mast height from D_WL: 46’ 7”14.2 m
Fore freeboard: 3’ 8”1.14 m
Mid-ship freeboard: 3’ 1”0.96 m
Light displacement (M_LC): 6834 lb3100 kg
Maximum displacement (M_LDC): 8157 lb3700 kg
Ballast weight: 1786 lb810 kg
Ballast type: Cast iron
French customs tonnage: 8.62 Tx

First 310's rig and sails

Upwind sail area: 562 ft²52.2 m²
Downwind sail area: 960 ft²89.2 m²
Mainsail area: 287 ft²26.7 m²
Genoa area: 274 ft²25.5 m²
Solent area: 238 ft²22.15 m²
Symmetric spinnaker area: 673 ft²62.5 m²
I iFore triangle height (from mast foot to fore stay top attachment): 37’11.29 m
J iFore triangle base (from mast foot to bottom of forestay): 10’ 10”3.3 m
P iMainsail hoist measurement (from tack to head): 37’ 11”11.54 m
E iMainsail foot measurement (from tack to clew): 13’3.95 m
Rigging type: Sloop Marconi 7/8
Mast configuration: Deck stepped mast
Rotating spars: No
Number of levels of spreaders: 1
Spreaders angle: Swept-back
Spars construction: Aluminum spars
Standing rigging: 1x19 strand wire continuous

First 310'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.: 20.0
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.: 264 ft²/T24.55 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.: 452 ft²/T41.96 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.: 26 %
Wetted area: 220 ft²20.4 m²
Prismatic coefficient iThe prismatic coefficient is obtained by dividing the volume of the boat (mass divided by the density of water) by the waterline length multiplied by the area of the maximum transverse section. This coefficient describes the effectiveness of a sailboat for a certain speed range: lower is the coefficient (<0.45), more effective the yacht is below its hull speed; higher the coefficient is, more the boat is suitable for planning speed.: 0.56
Righting moment @ 1° iThe righting moment is a moment (torque) that tends to restore a boat to its previous position after heeling. Its value corresponds to the torque needed to heel the boat for this angle. Higher the righting moment is for an angle, greater is the stability.: 477 lb.ft66 kg.m
Righting moment @ 30° iThe righting moment is a moment (torque) that tends to restore a boat to its previous position after heeling. Its value corresponds to the torque needed to heel the boat for this angle. Higher the righting moment is for an angle, greater is the stability.: 15594 lb.ft2156 kg.m
Maximum righting moment iThe righting moment is a moment (torque) that tends to restore a boat to its previous position after heeling. Its value corresponds to the torque needed to heel the boat for this angle. Higher the righting moment is for an angle, greater is the stability.: 17721 lb.ft2450 kg.m @ 50.00 °
Maximum transverse section: 9 ft²0.84 m²
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.: 7.20 knots