X-79

Sailboat specifications

The X-79 is a 26’1” (7.96m) racer-cruiser sailboat designed by Niels Jeppesen (Denmark). She was built between 1979 and 1994 by X-Yachts (Denmark) with 468 hulls completed.

X-79's main features

Model: X-79
Hull type: Monohull
Category: Racer-cruiser sailboat
Sailboat builder: X-Yachts
Sailboat designer: Niels Jeppesen
Country: Denmark
Construction: GRP (glass reinforced polyester):
Sandwich fiberglass polyester
Number of hulls built: 468
First built hull: 1979
Last built hull: 1994
Appendages: Keel : fin without bulb
Helm: Single tiller
Rudder: Single spade rudder
Unsinkable: No
Trailerable: No
Standard public price ex. VAT (indicative only): N/A €

X-79's main dimensions

Hull length: 26’ 1”7.96 m
Waterline length: 21’6.4 m
Beam (width): 9’ 5”2.88 m
Draft: 4’ 5”1.33 m
Light displacement (M_LC): 2965 lb1345 kg
Ballast weight: 1477 lb670 kg

X-79's rig and sails

Upwind sail area: 419 ft²38.9 m²
Downwind sail area: 800 ft²74.3 m²
Mainsail area: 219 ft²20.3 m²
Genoa area: 200 ft²18.6 m²
Solent area: 135 ft²12.5 m²
Stormjib area: 54 ft²5 m²
Symmetric spinnaker area: 581 ft²54 m²
Rigging type: Sloop Marconi 3/4
Mast configuration: Keel stepped mast
Rotating spars: No
Number of levels of spreaders: 1
Spreaders angle: 0 °
Spars construction: Aluminum spars
Standing rigging: 1x19 strand wire continuous

X-79'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.: 344 ft²/T31.93 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.: 656 ft²/T60.98 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.: 145
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.: 50 %
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.: 6.14 knots