Professional BoatBuilder - February-March 2018

52 PROFESSIONAL BOATBUILDER

RIG DESIGN: Fractional Update

rigged as a conventional slab reef.  e

reefed portions of the sail fall readily

into the sail pack.  e lazyjacks sup-

porting the sail pack are lead to below

the spreaders at 38% hoist, which is

lower than most sailmakers’ practice

but was done to minimize windage.

P-32’s Sail Plan

 e P-32’s sail plan has four fore-

sails: the self-tacking jib, an overlap-

ping dri er/reacher, an asymmetrical,

and a storm jib. Petrel’s working fore-

sail, set in most conditions, is the 6.77-

oz/yd (290-g/m^2 ) roller-ree ng frac-

tional jib of 150 sq  (13.9m^2 ), which

is 56% percent of the main. It is of the

same-weight cloth as the main and has

battens at the leech that are parallel

to the lu.  e jib club pivots on top of

the samson post, which is aba the

forestay so that the jib’s dra increases

as the mid-club primary sheet is eased

from the foredeck traveler.  e trav-

eler control lines allow the traveler car

to be adjusted athwartships, but it

turns out this is almost never neces-

sary since the club sags o just the

right amount to create the optimum

slot.  e two-part secondary sheet or

outhaul leads from a bale at the a end

of the club to the clew block, thence

back to a sheave at the end of the club

via the car on the jib club’s track.  is

allows the lead to be adjusted as the jib

is reefed.

Note that having a jib club avoids

the problem seen on many modern

designs where the sheet for a self-tack-

ing jib leads to a short transverse track

on the housetop. With such a con gu-

ration, once the car reaches the out-

board end of the track, the jib’s dra

becomes excessive, and a reaching

sheet needs to be bent on.

 e 4.77-oz/yd (204-g/m^2 ) near-

masthead dri er/reacher is a roller-

furling sail set  ying but normally le

up when furled. Its cloth weight is

heavy enough that its use is not

restricted to light air.  e clew is high

enough for it to be sheeted inboard

of the spreader tips in the space

between the lower leg of the diamonds

and the lower shrouds.

Sail packs and their lazyjacks have a multitude of con gurations and brand names.

Petrel’s sail pack departs from the norm in that instead of rising continuously from the

aft end of the boom to above the lowered headboard, it stays low to contain the bulk

of the sail below the relatively stiff sail-pack battens. Only the small triangular sections

at the mast protect the uppermost portion of the sail with its cars and the headboard.

To minimize windage, the lazyjacks lead to just below the spreaders at three-eighths

hoist rather than the common two-thirds or so hoist (at the upper spreaders). They are

rigged so the lazyjack-halyard tensions are split about half to the after legs, a quarter

to the forwards, and eighths to those in between. With the after legs’ shallow rise, the

upper full-length battens quickly clear the lazyjacks as the main is hoisted.

The jib club has a 2^1 ⁄ 4 "-square (57mm) cross-section with^3 ⁄ 8 "-mahogany (9.5mm) skins

over a foam core. There are solid wood inserts in way of the pivot and outhaul  ttings,

and an internal wood-and- berglass leaf spring at the midpoint to take the loads from

the midclub jibsheet. The jib club’s curve in pro le allows it to clear the lifelines as the

sheet is eased. A car running on the track on the top of the club serves to adjust the

outhaul lead as the jib is reefed.

JEP (BOTH)

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