Yachts & Yachting — March 2018

PAUL WYETH

trend away from iron keel fins with lead

bulbs, allied to an aluminium mast,

towards a plain all-lead fin and carbon

mast. The premise behind this is that the

rating penalty for the latter arrangement

is less than the performance gain. It’s

easy to see why this might be the case, at

least when sailing in waves, as velocity

prediction software that calculates

flatwater performance won’t take account

of the significantly reduced pitching.

However, with a secret rule it’s an

anomaly that could, at least in theory,

easily be tweaked as the rule is reviewed

on an annual basis. In any case, any likely

potential gains are relatively small

compared to the skill differences between

different teams.

DON’T MINIMISE RATING AT

ALL COSTS

Rating optimisation is often assumed to

be a process that minimises the rating for

a particular boat. However, that may also

be a misconception that is counter

productive as it ignores the basic premise

that you want the best possible

performance to rating ratio. As an

example, in 2016 Adam Gosling’s new

Yes! had a higher rating (at 1.052 almost

10 notches higher) than any other

JPK10.80. Yet he won Cowes Week

overall that year, as well as a host of other

silverware against stiff competition,

including lower-rated sisterships.

In the offshore sphere different boats

in the J/109 fleet have taken different

approaches. The ratings of the 14 boats

that finished the 2017 Rolex Fastnet

Race, for instance, ranged from 1.004 to

1.027. The first three on corrected time

had TCCs of 1.008, 1.010 and 1.017

respectively. The third boat was

sufficiently behind on the water that they

would have needed to shave 28 points

off the rating to beat the second on

corrected time, while the lowest rated

boat was fifth on corrected.

Of course, in a big fleet there will

always be examples of a boat that would

have got a better result with a marginally

lower rating, but don’t be tempted into

getting sucked into a series of changes

that offer diminishing returns when

there are more effective ways of rising up

the fleet to leading the pack. It’s worth

noting that, while many older boats no

longer race with overlapping headsails,

Mike Moxley’s 1998 HOD35 Malice was

rated with genoas when he won IRC

Class 2 in last year’s Hamble Winter

Series and Island Double.

HEADSAILS AND SPINNAKERS

AlthoughIRCisasecretrule,some

aspects arefairlywellknown.For

instance, headsail area is relatively

heavily taxed, which is why many older

boats that were designed with large

genoas now race only with smaller

non-overlapping jibs. This is generally an

easy choice for double-handed teams, but

fully crewed boats need to identify the

key conditions for which they want to

configure their boats.

If,forexample,theyaremost

interested in inshore results, then it’s a

given there will be less time spent in light

airs. In addition, on short windward legs,

or when short-tacking along a shoreline

against the tide, the time spent grinding

in a big genoa is inefficient, especially if

your crew work is less than perfect. That

means it may make sense to only rate

with non-overlapping jibs. For a boat

seeking offshore results the opposite

In 2016 Yes! had a higher rating than any

other JPK10.80 yet won Cowes Week overall

Above

Adam Gosling

has worked hard

to give Yes! the

best possible

performance

to rating ratio

OPTIMISING FOR IRC KEELBOATS

March 2018 Yachts & Yachting 33