Criado - NOR9207
Sailing performance analysis for a J-24 from 1978, built by J/Boats Inc and designed by JOHNSTONE.
Data provided by the Offshore Racing Congress (ORC) · Certificate issued 03/06/2025
This J-24 is a capable cruiser-racer with a good balance of performance and comfort. It reaches 5.3 knots upwind in 10 knots of wind, showcasing its strong upwind capabilities. Downwind, it achieves 4.7 knots, but the modest symmetric spinnaker means it may not keep pace with some peers. The large genoa complements the mainsail well, providing the power needed for versatile sailing conditions.
Sailing performance as a polar diagram
A polar diagram shows boat speed at different wind angles and wind speeds. The distance from center represents boat speed in knots, and the angle represents the boats angle to the wind. The wind speed is shown as true wind speed (TWS), not apparent wind speed. Likewise, the wind angle is shown as true wind angle (TWA), not apparent wind angle.
Beat: Sailing upwind (toward the wind)
Beam Reach: Sailing across the wind
Run: Sailing downwind (away from the wind)
VMG Performance
Wind Speed (columns): True wind speed (TWS) in knots - the actual wind speed, not the apparent wind you feel on deck.
VMG (Velocity Made Good) is your effective speed toward your destination, not your actual boat speed.
Beat VMG (top bars): Speed made good when sailing upwind. Higher is better - it means you're reaching the windward mark faster.
Run VMG (bottom bars): Speed made good when sailing downwind. Higher is better - it means you're reaching the leeward mark faster.
Measured sails
Spinnaker measurements were not supported before this season's certificates. If no spinnaker is shown, that's why.
Measurements
Identity
Dimensions
Sail Areas
ORC Rating
Rated boat speeds
| Wind Speed (TWS) | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| 4 kt | 6 kt | 8 kt | 10 kt | 12 kt | 14 kt | 16 kt | 20 kt | 24 kt | |
| Beat VMG | 2.26 | 3.07 | 3.67 | 4.08 | 4.33 | 4.40 | 4.42 | 4.37 | 4.16 |
| 52° | 3.51 | 4.67 | 5.43 | 5.82 | 6.04 | 6.14 | 6.18 | 6.21 | 6.14 |
| 60° | 3.74 | 4.91 | 5.61 | 5.96 | 6.17 | 6.31 | 6.37 | 6.45 | 6.43 |
| 75° | 3.89 | 5.05 | 5.70 | 6.06 | 6.32 | 6.54 | 6.69 | 6.86 | 6.94 |
| 90° | 3.80 | 4.96 | 5.68 | 6.13 | 6.44 | 6.63 | 6.87 | 7.24 | 7.49 |
| 110° | 3.61 | 4.85 | 5.71 | 6.19 | 6.58 | 6.94 | 7.30 | 7.91 | 8.53 |
| 120° | 3.44 | 4.69 | 5.58 | 6.09 | 6.49 | 6.89 | 7.31 | 8.58 | 10.03 |
| 135° | 3.04 | 4.20 | 5.13 | 5.83 | 6.25 | 6.63 | 7.03 | 8.18 | 11.16 |
| 150° | 2.47 | 3.57 | 4.55 | 5.36 | 5.93 | 6.30 | 6.66 | 7.47 | 9.34 |
| Run VMG | 2.13 | 3.09 | 3.95 | 4.68 | 5.34 | 5.81 | 6.17 | 6.83 | 8.09 |
Boat speed (knots) at wind angle / wind speed