Tips on developing your polar diagrams to improve your boat speed

There requires a lot of efforts for sailors to match the perfect sailing experience. No matter the crew is good, the bottom is clean, but you need an extra element that helps your boat to get the perfect blend with the rest of the boats sailing across the water. Every sailor needs to set a targeted boat speed and need to follow it as better as possible. For this, the requirement of having a polar diagram is a must.
A polar diagram is a particular way of plotting the boat speed generated at all angles to the wind for various wind speeds. Here, the term polar is used because the boat speed curve is plotted by using polar coordinates.
It is an electronic compass along with diagram which shows the speed of the wind along the vertical axis and from top to bottom. All you need is to visualize your boat’s heading in the same way as displayed in the polar diagram. Then, the boat speed achieved by the yacht under a given wind speed a given angle to the wind is determined. This speed can either be measured in the water, or estimated using "Velocity Prediction Programs"

Calibration is King

Calibration is the most vital process that is used to maintain the accuracy of your instruments. Calibration is the process of configuring an instrument to provide a result for a sample within an acceptable range. Eliminating or minimizing factors that cause inaccurate measurements is a fundamental aspect of any instrumentation design. No matter it is an AIS or a polar diagram, you have to calibrate your instruments for better performance and better speed of your boat.

Don’t believe the VPPs

A velocity prediction program i.e. VPP is a program which solves for the performance of a sailing yacht in various wind conditions by balancing hull and sail forces. As the name itself suggests, it’s only the prediction of the program about the polar diagram. It may be under-predicting, so you just can’t rely on prediction programs for maintaining the speed of your boat. Besides, such predict programs are not accurate when compared with programs use Computational fluid dynamics.

Theory to reality

The core reality behind every nautical instrument is that they only reflect the assumption and computer model they are designed for. And the instruments are designed to display the set of targets for a particular boat. Results can vary from boat to boat. You must need to consider these factors before heading to the judgment of a polar diagram. The following factors can also affect the accuracy of your polar diagram.

• Displacement


• Sailpan


• Alloy or carbon rig


• Shallow or deep keel type


• Weight of crew


• Basic necessities

Good Sailing

The saying does say the truth, "A smooth sea never made a skilled sailor". The skills of sailor are the best instrument to trust while diving into the deep ocean. The experience and skills of a sailor can overtake even the best polar diagrams and instruments on board. You can even build an invaluable guide for the helmsman and trimmers with your experience and with your collected data. No matter how expensive the boat is and how costly the boat equipment is, you can provide an unmatched experience with your sailing expertise.

Build your own Polar Diagram

Sail like the professional sailors by building your own polar diagram. For this, all you need is the experience and practice. You can start practicing by acknowledging your target and noting down your performance. And repeating this again and again until you have reached the highest level of your capabilities. You can even use different sort of applications like iPolar to judge your performance and to sail like a pro.
Maintain the calibration, avoiding VPPs and using applications can help you to develop a better speed of your boat. This even helps you to excel your sailing skills and expertise.
How do you find the polar diagram for measuring your boat speed? Discuss in the comment box below.

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