Jervis Bay Sailing Club

Program for Jervis Bay Sailing Club

Jump to Courses and Information
Please click  DRAFT 2024-2025 CALENDAR/PROGRAM  for a copy of the Program in PDF.
Note: Please advise us of any changes in the program of events so that the program can be updated
For a simple way to measure distances to set leg length try this free Walk Meter App. It uses your phones inbuilt GPS and is free and easy to use. An even simpler one is the Measuring Wheel app for Android. Set the screen timeout to 30 minutes. There is a similar one for Apple devices Pace Ruler (Apple) See the guides below for target leg lengths for various types of races and wind strengths.

For Latest Minutes Advantage Handicaps for Pointscore Races in PDF click  HERE for Results Sheet  HERE for Sign-On/Off Sheet  Sign On Sheet

NOTE: If races at JBSC are cancelled due to bad weather, or other issues, sailors could consider sailing with => Nowra Community Sailing Club

EARLY DRAFT Jervis Bay Sailing Club 2024-2025 Calendar/Program

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Course Area Map - Hare Bay

Courses and Race Length Information

The racing 'window' is generally 90 to 120 minutes, meaning with a start at 1330 hours the racing is generally completed by 1530 or 1600 hours (for all to finish), with shortened courses applied if necessary.

The Club runs three series throughout the season using various courses (see below):

• Championship (scratch start).
• Sprint (scratch start).
• Pointscore (handicap start).

Shortcut for Courses / Times / Leg Lengths

Common Courses - Olympic Triangle with Port Roundings (Red Flag) (as shown in diagram); Starboard roundings can be used (Green Flag)

For a definitive guide for setting courses of various types and configerations see the Set Courses App

The courses for the three events run by the club are:
Sprints (scratch start / yardstick) - Aim for 4-6 races each Sprints Day, back-to-back
=> Indicative Race Duration 20 minutes (550 m leg lengths in around 10 knots)
=> Start-Triangle-Sausage-Finish

Championship (scratch start / yardstick) - Aim for two races on each Championship Day, back-to-back
=> Indicative Race Duration 45 minutes (800 m leg lengths in around 10 knots)
=> Start-Triangle-Sausage-Triangle-Finish

Pointscore (handicap start - minutes advantage)
=> Indicative Race Duration 90 minutes (1100 m leg lengths in around 10 knots)
=> Start-Triangle-Sausage-Triangle-Sausage-Finish
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Indicative 60-60-60 Triangle leg lengths for race duration for various wind speeds

Note: You can vary the reach angle for various classes (tighter and broader reaches). This will require an adjustment for the reach length relative to the windward leg when setting the course:
55 deg => 0.87 of windward leg
60 deg => 1.0 of windward leg
65 deg => 1.2 of windward leg
70 deg => 1.46 of windward leg

Note for quick reference guide:
Yellow Marine Park buoys => 1380 m apart
Red Hazard Buoys => 800 m apart

Pointscore

Championship

Sprints

Laser Speeds for Upwind, Runs and Reaches under various wind strengths

See this link for additional leg length guides for Regattas

REGATTA - Indicative Leg lengths for race duration under various wind speeds
Expected times for Olympic classes for Up-Back Courses (winds/leg length)

Post-Race Adjustments to the Pointscore Handicap Systems

Note: For the Pointscore the slower yachts are given several minutes start ahead of the faster yachts ('Catch me if you can'). Ideally all yachts should finish very close together.

The handicaps are adjusted after each race according to the following scheme:
1st place => loss of 2 minutes
2nd place => loss of 1 minute
3rd place => no change - stay as you are
4th place and all other starters (including DNF & Duty Officer) => plus 1 minute
All non-starters have no change to their handicaps, except when all the scores need to be adjusted to avoid negatives. For example, when the winner has a Minutes Advantage Handicap of 1 minute and would lose 2 minutes, to produce a '-1 minute' handicap for being in first place, ALL handicaps are increased by 1 minute so that the winner's new handicap is 0 (zero).
Note: The committee and handicapper will make periodic adjustments to the system to keep it as fair and functional as possible, and to assign handicaps to new members and visitors.
See the latest Minutes Advantage Handicaps as PDF

Course Area Distance Guide (see attached map below)

• Note: You cannot anchor the start boat in the Sanctuary Zone (East of the line from Red Rock to the NS line of the Yellow Park Buoys)
• Note: You cannot position a course mark (wheel hub) in the designated sea grass protection area => East of the line from Red Rock to the first Yellow Park Buoy (8C) and from 8C buoy to the Green Point Marker (aligned with Cabbage Tree Point)
• 1550 m between Yellow Marine Park buoys
• 820 m between two Red port buoys (Brolga and Point Buoys)
• 1640 m; 1730 m (southern) between Point Red Buoy to Yellow Marine Park buoys
• 1580 m from Red Brolga Buoy to Yellow Marine Park buoy A1
• 1910 m from Red Brolga Buoy to Red Rock
• 1050 m from Red Rock to Yellow Marine Park buoy A1
• NOTE: Do not anchor the Start Boat inside the Sanctuary Zone East of Yellow Buoys
• NOTE: Do not place Course bouys inside the seagrass protection area,
  North of Line from A1 (top yellow buoy) to Green Island Point Marker

Incidentally => From the Red Point buoy to the top Yellow Marine Park buoy (A1) is NE and 1640 m in length, so setting bottom mark 300 m out from red buoy in that direction and setting the top mark after travelling 800 m towards the A1 Marine Park Buoy gives a great default set up for prevailing NE winds with an ideal leg length of about 800 m.

Note: Leg lengths can be set using the yellow GPS tool, or an app you install on your phone, or the Map Plotter, or by motoring at a constant speed or revs between the two red buoys and noting the time taken for this 800 m distance. Motor for the same time and speed to set the distance between the buoys for your course.

See the Map below for the distances between key markers in the bay

Download the map as a PDF Course Area Distance Guide

Expected Race Times for Various Yardsticks

Interesting Yardstick Comparisons

The yardsticks and times shown below provide some interesting match-ups.
The Aero options are vastly different 5 to 9 => 116.8 to 109.3, spans Laser Radial to Taser. With such a light-weight hull, performance will be markedly affected by skipper weight.

• Laser 4.7 similar to Spiral
• Laser Radial similar to Aero 5, which is a bit faster
• Aero 7 faster than Laser Full, and very similar to Finn
• Aero 9 similar to Taser, Aero 9 is super fast.

Class	Yardstick	Expected time for 90 min race	Minutes advantage so all finish in dead-heat
Laser 4.7	125	72	18
Spiral	124	73	17
Laser Radial	118.5	76	14
Aero 5	116.8	77	13
Laser Full	114	79	11
Aero 7	112.5	80	10
Finn	112	80	10
Aero 9	109.3	82	8
Taser	108	83	7

Additional Comparisons

Yacht	Sail Area	Yardstick	Hull Length	Hull Weight (kg)
Finn	10.6	112	4.5	107
Laser	7.1	114	4.2	59
Laser Radial	5.8	118.5	4.2	59
Laser 4.7	4.7	125	4.2	59
RS Aero 5	5.2	116.8	4.01	33
RS Aero 6	6.2	114.6	4.01	33
RS Aero 7	7.4	112.5	4.01	33
RS Aero 9	8.9	109.3	4.01	33
Spiral	6.5	124	3.8	55
Spiral (small )	5.6	131.5	3.8	55

Common Signal Flags