Pacific Cup Sail Selection

Pacific Cup Sail Selection

Presented by Kame Richards / Pineapple Sails

 

1.     COURSE DESCRIPTION

a.     How big a deal is this 2,070 mile event?  I did the following very scientific calculation for the 2006 Single Handed Sailing Society’s TransPac:  It compares the time spent racing for a season locally, versus sailing the SSS TransPac.  I used the 10th place finisher in their single handed division.  I used elapsed time, not corrected time.

      i.     The 2005 racing season took 47 hours of racing (not including the Long Pac)

      ii.     The 2004 Single handed TransPac took 373 hours of racing

      iii.     This is 7.92 YEARS of SSS racing at a shot, and this assumes you SHIP the boat home!!!

The difference between racing locally and racing across the ocean is that, once you have started, all of the servicing and repairs to your boat must be done by those onboard, and using materials that are onboard.  You can’t go to the store, you can’t call a rigger.  You have to fix it yourself.

b.     Wind mix over the race course (see next page)

 

2.     LEVEL OF PERSONAL COMMITMENT

a.     Have you done this before?

b.     Is this a prelude to going cruising?

c.     How badly do you need/want to win

d.     Minimum and maximum efforts

e.     The event should be a LOT of FUN

 

3.     BUDGETING / PRIORITIES

a.     Short range / long range

b.     Upwind sails

c.     Reaching sails

d.     Downwind sails

 

4.     SAIL SELECTION

a.     Your boat’s performance envelope

b.     How long/fast is your boat?

c.     Mainsail:  batten length, sail cloth, reefs

d.     Jibs/genoas: hanks/furling, sail cloth, twin headsails

e.     Spinnakers: symmetric, asymmetric, reaching, running, sail cloth, spinnaker socks

 

This “Wind Mix” table has been used in the past by Pacific Cup Yacht Club to determine ratings.  It represents a studied breakdown of the various wind angles and strengths typically found between the start in San Francisco and the finish in Kaneohe.  This is not a promise of what will be, but several experienced people put a lot of time into determining these values.

 

True Wind Angle

True Wind Speed

Distance

Distance

 

Degrees

Knots

Miles

Cumulative

Comments

Opt. Beat

16

6

6

Beating out of San Francisco Bay

Opt. Beat

20

8

14

 

52

16

14

28

Close reaching past the Farallon Islands

52

20

22

50

 

60

20

75

125

 

75

20

150

275

 

75

24

75

350

Wind

90

16

70

420

Slowly

110

16

70

490

Swinging

110

20

50

540

aft --

120

12

50

590

 

120

16

10

600

 

135

10

100

700

To this point, about 1/3 of race is reaching.

150

12

115

815

 

150

20

240

1055

 

150

24

100

1155

 

Opt. Run

6

20

1175

At this point the race is only about half done,

Opt. Run

8

40

1215

And the remainder is sailing as low as you possibly can.

Opt. Run

10

80

1295

 

Opt. Run

12

120

1415

 

Opt. Run

16

135

1550

 

Opt. Run

20

300

1850

 

Opt. Run

24

220

2070

 

 

In terms of sail selection, you are looking for an inventory that best covers these conditions.  Note that the anticipated wind strength varies between 6 and 24 knots.  In squalls, chances are you will see a lot more than 24.  And at other times, I have seen a lot less than 6 knots too!

 

True Wind Angle: different from apparent wind angle by subtracting out the vector effect of the boat’s speed from the apparent wind angle

True Wind Speed:  different from apparent wind speed by subtracting out the vector effect of the boat’s speed from the apparent wind speed

 

If you like pictures more than numbers, here is a different representation of the “Wind Mix” table above. 

 

This is grib image showing the race course on July 10, 2006.  This date has been selected because it is fairly representative of what are “typical” wind patterns for the race, even though this pattern is getting harder to find.  You can see the wind birdies showing the wind strength and direction between San Francisco and Kaneohe. 

 

Your sail inventory needs to deal with the changing conditions along the route.

 

The navigator’s dilemma is that if you sail a looping path, first to the south and then to the west, you have more wind to play with, but the distance sailed gets longer.  If you sail the shortest possible distance, there will very light winds half way across.

 

 

Interpretation of grib files, as well as where to get grib files and a grib file viewer will be presented at a later seminar.
Minimum Effort

Main

#3 jib

.75 GP spinnaker

storm sails (as required)

 

Maximum effort (symmetric spinnakers)

Main

#1 genoa

#2 genoa

#3 jib

jib-top (high-clewed reaching genoa, 155%)

blast reacher (high-clewed reaching genoa, 125%+/-)

.5 ounce VMG spinnaker

.6 ounce GP

.75 ounce reacher

.75 ounce runner

1.5 ounce GP

1.5 ounce “shy kite”

spinnaker staysail

several back-up spinnakers

storm sails (as required)

On the morning of the race, try to decide if some of the sails can be left behind.  Basically, sails add weight.  The heavier a boat is, the slower it will go to Hawaii.  If the probability of using some sail(s) is low, then maybe it/they should be left behind. Likely candidates for being left behind:  #1 genoa if it is windy at the start, jib-top if the reach looks like it will be windy.  Unlikely candidates to be left behind: any spinnakers.

 

Asymmetric spinnakers:  It is generally agreed that asymmetric spinnakers tend to reach very well.  Certainly an optimized reaching asymmetric sail will out reach and optimized reaching symmetric spinnaker.  What is less generally agreed is how well the asymmetric sails run.  Some of the factors that affect the A-sail’s ability to run are: the characteristics of the boat (displacement, sail area, hull shape); the length of spinnaker pole; can the pole be rotated aft; and how big is the spinnaker.  In addition to the changes in performance, there is the issue of the effect of the boat’s handicap.  Some research will be required to determine the answers to these questions. 

 

Again generally, asymmetric spinnakers tend to benefit boats that travel at high rates of speed as opposed to “displacement boats” which are more inclined to sail at similar speeds down wind as they do up wind.  If your boat isn’t capable of sailing at sustained speeds of 15 knots down wind, then asymmetric spinnakers may not be the right choice.  Review the drawing at the bottom of page 2 to understand how differently a fast boat and a slow boat see the same 20 knots of true wind, at the same 135 degree true wind angle

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