Sailboat specifications and datasheets

Westerly Longbow sloop

The Westerly Longbow, here in "sloop" version, is a 31’2” monohull sailboat designed by John Laurent Giles. She was built by Westerly (United Kingdom) and made of GRP (glass reinforced polyester). This sailboat was produced between 1971 and 1980 with 265 hulls completed.

The Westerly Longbow is as well listed, on, in version Ketch.

Westerly Longbow Westerly Longbow sailplanWesterly Longbow layoutWesterly Longbow layoutWesterly Longbow sailingWesterly Longbow sailingWesterly Longbow sailingWesterly Longbow accommodationsWesterly Longbow accommodations
Westerly Longbow's   Main Features
Model Westerly Longbow
Version Sloop
Type of hull Monohull
Category Cruising sailboat
Designer John Laurent Giles
Construction GRP (glass reinforced polyester)
First built hull 1971
Last built hull 1980
Number of hulls built 265
Appendages Keel :
Fin without bulb
Helm 1 tiller
Rudder 1 rudder on skeg
Cockpit Closed aft cockpit
Unsinkable No
Trailerable No
Standard public price ex. VAT (indicative only) N/A
Westerly Longbow's   Main dimensions
Length overall 31’ 2”
Hull length 31’ 2”
Waterline length 24’
Beam (width) 9’ 6”
Draft 4’ 6”
Mast height from DWL 41’ 7”
Light displacement 8378 lbs
Ballast weight 3990 lbs
Westerly Longbow's   Rig and sails
Upwind sail area 540 sq.ft
Mainsail area 207 sq.ft
Genoa area 334 sq.ft
Solent area 237 sq.ft
Jib area 152 sq.ft
Stormjib area 61 sq.ft
Rigging type Sloop Marconi masthead
Rotating spars No
Mast position Deck stepped mast
Spars Mast and boom in Aluminum
Standing rigging 1x19 strand wire continuous
Number of levels of spreaders 1
Spreaders angle 0 °
Westerly Longbow's   Performances
Upwind sail area to displacementiThe 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 23 it indicates a fast sailboat.
Displacement-Length ratio (DLR)iThe Displacement Length ratio is a figure that points out the boat's weight compared to its waterline length. 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.
Ballast ratioiThe Ballast ratio is an indicator of the stability; it is obtained by dividing the boat's displacement by the weight of the ballast. Since the stability depends also of the hull shape and the position of the center of gravity, only boats with similar ballast arrangements and hull shape should be considered.
Higher the ballast ratio is, greater is the stability.
48 %
Hull speediAs 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.
6.56 knots
Westerly Longbow's   Auxiliary engine
Engine(s) 1
Engine type Inboard engine
Engine 25 HP
Fuel type Diesel
Westerly Longbow's   Accommodation
Cabin(s) 1
Berth(s) (min/max) 4 / 6
Head(s) 1

Similar sailboats that might interest you :

Compare4 max.SailboatHull lengthFirst built hull
Westerly Renown Sloop31’ 2”1972
Symphonie Deep draft31’ 2”1978
Moody 31 MkI Fin keel30’ 8”1983
Brin de folie Standard29’ 6”1975
Dufour 3800 Deep draft30’ 6”1980
Hallberg-Rassy 312 MkII30’ 11”1986
Jouët 920 Deep draft30’ 5”1979
Shipman 2828’ 11”1969
Melody Deep draft33’ 7”1976
Hallberg-Rassy 33 Mistral33’ 5”1966
Super Daïmio Deep draft27’ 7”1975
Albin Nova 3332’ 5”1981
Westerly Centaur Sloop25’ 11”1969
Albin Ballad30’1971
Attalia 32 Deep draft30’ 2”1983