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## What is a number 1 sail?

Racing sails are generally given a number to describe the sail’s size. A #1 would be **the largest genoa in an inventory**, a #2 the next largest, and so on. A # 3 is usually the largest non overlapping sail in the inventory. This sail is also often called a blade.

## How do you measure jib size?

The best way to measure the tape is to use **Calipers that can measure in millimeters**. If you don’t have a set use a set of drill bits and either slide them up the track in your furling system or hold them up to the luff tape on your existing sail to determine the proper size.

## How is Luff calculated?

It uses Heron’s Formula to calculate the area of the sail, then uses the basic formula for area of a triangle to calculate the luff perpendicular: **area = ½ base × height, solving for height (LP)** where the “base” is the luff. The LP is then divided by the J measurement and multiplied by 100 to make it a tidy percent.

## What is the length of a sail?

The average overall length (LOA) of common production monohull sailboats is **30 feet**, and the average LWL is about 25 feet. The average length of production multi-hull sailboats is between 40 and 44 feet.

## What is the best sail shape?

The best shape for acceleration has **the draft fairly far forward**. Upwind — When a boat is sailing into the wind, you want sails that are relatively flat. Flatter sails reduce drag when sailing upwind and also allow you to point a little closer to the wind.

## What Is a Number 4 sail?

# 4 Jib. Reduced size Jib for use when the mainsail is reefed or nearly reefed. This sail is **short of maximum luff length** and has a reduced foot length to allow effective steering in large waves and reduce mainsail backwind.

## What is the purpose of a stay sail?

The staysail plays three roles: **It augments sail power**. It helps break down total sail area into smaller working components for ease of handling. The smaller sail units allow for different combinations, giving sailors a variety of options for different conditions.

## How do I choose a sail number?

Sail numbers are generally **assigned in consecutive order**. They are assigned by either the builder, class association (for inland competitive racing), or national authority (required for offshore racing yachts). It isn’t mandatory to register an official number. If you don’t compete you may assign your own number.

## What is a Code 0 sail?

A code zero is strictly **a downwind sail**.

A code zero is often classified as a spinnaker in terms of racing, hence the restriction on the length of the mid-girth, but it’s not a true downwind sail. If you’re going downwind, you’ll use either a symmetrical or asymmetrical spinnaker.

## How do you get a sail number?

Place **the number within the pencil outline** and press down to stick the peeled back area . Lift the remainder of the number and slowly peel off the backing as you smooth the number onto the sail, taking care to remove air bubbles and creases as you go .

## How is boom length measured?

Boom lengths are taken from **the mast front to the leech edge at the upper eyelet at the clew**. The tape measure end is hooked on the sail edge just above the eyelet, letting it settle against the eyelet and outhaul line.