First 18 Swing keel

Sailboat specifications

The First 18 is a 18’ (5.5m) cruiser-racer sailboat designed by Groupe Finot (France). She was built between 1978 and 1982 by Bénéteau (France) with 1065 hulls completed. The Swing keel version features an appendage configuration without compromise between draft and performance. The only drawbacks are the space is taken inside and the effort needed to lift the keel....

The First 18 is as well listed, on Boat-Specs.com, in Fin keel version (see all the versions compared).

First 18's main features

Model: First 18
Version: Swing keel
Hull type: Monohull
Category: Coastal cruiser-racer sailboat
Sailboat builder: Bénéteau
Sailboat designer: Groupe Finot
Sailboat range: First
Sailboat collection: Micro
Country: France
Construction: GRP (glass reinforced polyester):
- Hull: Single skin fiberglass polyester
- Deck: Sandwich balsa fiberglass polyester
Number of hulls built: 1065
First built hull: 1978
Last built hull: 1982
Appendages: Lifting keel : swing keel
Helm: Single tiller
Rudder: Single transom hung rudder
Unsinkable: No
Trailerable: Yes
Former French navigation category: 4
Standard public price ex. VAT (indicative only): N/A €

First 18's main dimensions

Overall length: 19’ 5”5.9 m
Hull length: 18’5.5 m
Waterline length: 16’ 7”5.05 m
Beam (width): 7’ 11”2.4 m
Waterline beam (width): 6’ 5”1.94 m
Draft: 3’ 7”1.1 m
Draft when appendages up: 1’ 10”0.55 m
Fore freeboard: 2’ 7”0.79 m
Mid-ship freeboard: 2’ 4”0.69 m
Light displacement (M_LC): 1323 lb600 kg
Maximum displacement (M_LDC): 2293 lb1040 kg
Ballast weight: 397 lb180 kg
Ballast type: Cast iron
French customs tonnage: 2.68 Tx

First 18's rig and sails

Upwind sail area: 189 ft²17.55 m²
Downwind sail area: 307 ft²28.5 m²
Mainsail area: 108 ft²10 m²
Genoa area: 81 ft²7.55 m²
Jib area: 54 ft²5 m²
Stormjib area: 22 ft²2 m²
Symmetric spinnaker area: 199 ft²18.5 m²
I iFore triangle height (from mast foot to fore stay top attachment): 22’ 7”6.9 m
J iFore triangle base (from mast foot to bottom of forestay): 6’ 7”2 m
P iMainsail hoist measurement (from tack to head): 22’ 6”6.85 m
E iMainsail foot measurement (from tack to clew): 8’ 6”2.6 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: Continuous

First 18'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.: 3.0
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.: 266 ft²/T24.67 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.: 132
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.: 30 %
Wetted area: 108 ft²9.99 m²
Maximum transverse section: 4 ft²0.37 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.: 5.45 knots