Sailing Terminology

Sailing Terminology

🌬️ Close-Hauled Sailing

Sailing boats cannot head directly into the wind. When the wind is coming from directly ahead, the sails don’t fill with wind; instead, they flap like a flag hanging on a pole. However, if the wind comes at an angle of about 30–35 degrees, sailing boats can move. This type of sailing against the wind at narrow angles is called “close-hauled sailing”.

⛵ Beam Reach

Beam reach is when the wind comes from the side, at an angle of about 55 to 160 degrees. This type of sailing produces less heeling force compared to close-hauled sailing and is therefore generally considered the fastest sailing method.

📐 Types of Beam Reach

  • Close Reach: Wind is coming from an angle of 55°–80°.
  • Broad Reach: Wind is coming from an angle of 110°–160°.

🌪️ Running

Running is one of the oldest forms of sailing in history. This sailing type occurs when the wind comes from directly behind, and it requires attention. A small mistake at the helm or a sudden change in wind direction can cause the mainsail to fill from the opposite side and abruptly swing to the other side. This situation is called an unintentional gybe and can be dangerous.

🔄 The Concept of Tack

The concept of tack is important in close-hauled and beam reach sailing. Tack is determined according to the direction the wind is coming from:

  • If the wind is coming at a 90° angle from the starboard side: Starboard tack beam reach
  • If the wind is coming at a 90° angle from the port side: Port tack beam reach

This distinction is used to determine the right of way between sailing boats.

🚫 No-Go Zone and Tack

In the 90° no-go zone where the wind is coming directly from the front and the boat cannot move forward, the concept of tack does not apply. Sails do not generate thrust in this area.

In running, because the wind comes from behind, determining the tack is also difficult. However, as an approximate indicator, the direction of the boom can be used:

  • If the boom is on the starboard side → Port tack
  • If the boom is on the port side → Starboard tack

🌬️ Windward – Leeward Concept

To understand the concept of windward and leeward, imagine the wind as particles moving in the direction of flow. The side these particles hit is the windward side. The side they don’t hit is called the leeward side.

📈 Heading Up – Bearing Away

Heading up (luffing) means turning the boat toward the windward side. For example, when the wind is coming from the side and the helmsman is told “HEAD UP,” the boat starts taking the wind more from the front.

Bearing away (falling off) means turning the boat toward the leeward side. In the same scenario, when the command “BEAR AWAY” is given, the boat starts taking the wind more from behind.

These two maneuvers are also defined as “luffing” (approaching the wind) and “falling off” (moving away from the wind).

🔁 Tacking

A boat sailing close-hauled on port tack must head up toward the windward to change to starboard tack, passing through the 90° “no-go zone” where sailing is not possible. This maneuver is called a tack.

🧭 Points to consider during a tack:

  • The boat should have enough speed before initiating the tack.
  • The transition through the no-go zone should be quick, without stalling.
  • If there is not enough speed, first gain speed with a beam reach, then initiate the tack.

❗ If the boat stalls in the no-go zone during the tack and cannot complete the turn, it becomes stuck and cannot move in any direction. This is called getting caught in irons.

🔄 Gybing

Gybing is the turn made by moving away from the wind. For example, a boat on a broad reach on port tack enters a run, then gybes by shifting the boom to the other side, and returns to a broad reach.

There is no no-go zone during a gybe, but:

  • Since the wind comes from behind, the boom can shift very violently.
  • Gybing maneuvers should be slow and controlled.
  • The helmsman should execute the turn smoothly and steadily.
  • It is recommended to guide the boom manually or ease the sheet in a controlled manner.

⚠️ Failed Tack

A failed tack occurs when the boat stalls in the no-go zone during a tack and cannot continue. In this case:

  • The sails don’t fill, the boat turns into the wind and stalls.
  • The rudder loses effectiveness because there is no movement to steer the boat.

✅ Tips to Avoid a Failed Tack

  • Check if the speed is sufficient before tacking. If needed, fall off briefly to a beam reach, then tack.
  • After exiting the tack, enter a beam reach before heading back to a close-hauled course.
  • During a tack, crew members must change positions at the right time.
  • Be extra cautious when changing tack with a genoa (jib).

🚫 Escaping from a Failed Tack

The first rule for escaping from a failed tack is, as always, to stay calm. In this situation, since there is no propulsive force on the sailboat, the rudder becomes ineffective. Therefore, instead of steering with the rudder, you should aim to turn or accelerate the sailboat by adjusting the sails.

When the sailboat is in a failed position, it will eventually start drifting backwards. During this time, due to the resulting momentum, turning the rudder in a fixed direction and waiting can help the boat’s bow to rotate.

  • ⛵ Pushing the mainsail manually speeds up the process.
  • 💨 Backwinding the jib helps turn the sailboat’s bow.

⚙️ What is Trim?

Trim refers to adjusting and setting the sail according to the wind. The sail’s position and tension are adjusted based on the wind angle to achieve maximum performance.

🚢 Working Principle of Sailboats

Sailboats generate propulsive force using the wind based on two main principles:

  1. Kinetic effect: The direct push resulting from wind hitting the sail.
  2. Aerodynamic effect: The suction force created by modern sail shapes based on Bernoulli’s principle.

In the early days, sailboats could only move with the wind from behind, whereas modern sailboats today can sail at an angle of 45° to the true wind.

This advancement was made possible by the evolution of sail design, hull shape, and keel systems. To better understand this aerodynamic structure, let’s take a look at Bernoulli’s Principle.

📚 Bernoulli’s Principle

The Swiss mathematician Daniel Bernoulli, who lived in the 18th century, conducted the first fundamental studies on fluid dynamics. According to Bernoulli’s Principle:

  • The outer surface of the sail is longer than the inner surface.
  • This difference causes the air on the outer surface to speed up and creates a low-pressure area.
  • The low pressure pulls the sail towards it and propels the sailboat forward.

✈️ This principle is also used on airplane wings. Modern sailboats operate based on this principle.

🎯 Heeling Force

The entire force generated by the sail is not used for forward motion. A portion of it causes the boat to heel. This is called heeling force.

To counterbalance this force:

  • Keel weight (the ballast under the boat)
  • Proper crew positioning

are of great importance. When balance is achieved, the boat moves forward.

🌬️ Apparent Wind vs. True Wind

True wind is the natural wind speed in your location. Apparent wind is the wind felt on the sailboat.

For example:

  • True wind: 15 knots
  • The boat is sailing downwind at 5 knots
  • Apparent wind = 15 – 5 = 10 knots as felt onboard

🏄‍♂️ Apparent wind changes as the sailboat's speed increases, and this affects sail trim and sailing strategy.