The direction of motion of the yacht relative to the wind. How does a sail work? Finding wind directions relative to you

The course of a ship relative to the wind is the angle between the direction of the wind and the center line of the ship, that is, the heading angle to the point on the horizon from where the wind is blowing, expressed in angular degrees or bearings.

Depending on the magnitude of this angle, courses relative to the wind have their own names:

1 - steep close-hauled (30° - 45°);

2 - full close-hauled (45° - 75°);

3 - gulfwind (about 90°);

4 - backstay (110° - 160°);

5 - gybe (160° - 200°);

6 - left (30° on each side)

Leventik (French le vent) - a course that forms an angle close to 180 degrees with the wind direction, that is, the wind blows almost exactly in front of the ship. Since a sailing ship cannot follow such a course, they usually say not “course”, but “left-hand position”.

Beidewind (Dutch bij de wind) is a course at which the angle between the direction of the wind and the direction of movement of the vessel is more than 100 degrees (less than 8 points). There are close-hauled winds: full (from 100 to 120 degrees) and steep (more than 120 degrees). The thrust of a sail is entirely determined by its lifting force; with increasing drag, the thrust force decreases, but the drift force increases. Thus, on this course, the sail, installed with a minimum angle of attack to the apparent wind (5-10 °), works like an aerodynamic wing.

The best sailing ships sail at an angle of 30-35° to the direction of the true wind. Due to the addition of the wind speed vectors and the oncoming air flow, the apparent wind speed on a close-hauled course turns out to be maximum, as well as the aerodynamic force on the sail, proportional to the square of the wind speed. The drift force also reaches its maximum value. If you try to sail at a sharper angle to the wind, the speed of the vessel will decrease, the sail will begin to flap, the aerodynamic force will decrease and, finally, a moment will come when the drag of the sail and the resistance of the water to the movement of the boat will far exceed the thrust. The ship will reverse.

Gulfwind (Dutch halve wind), or half wind - a course at which the angle between the direction of the wind and the direction of movement of the vessel is approx. 8 directions (from 80 to 100 degrees). On this course the wind blows perpendicular to the port, and the apparent wind is directed from the bow at an acute angle to the port. Accordingly, the sail is set at a lower angle of attack, its thrust is equal to the lifting force, and the drift force is equal to the drag of the sail. on this course the sail should divide the angle between the DP and the direction of the apparent wind approximately in half.

Backstay (Dutch bakstag) - a course that forms an angle with the wind direction of more than 8, but less than 16 points (more than ten and less than eighty degrees), that is, the wind blows from the rear-side in relation to the ship; They are distinguished by a full backstay course, at which the angle is no more than twenty degrees, that is, approaching the gybe; the sail is set at an angle to the wind on the leeward side. Usually on this course a sailing ship develops its highest speed. At the backstay, the sail operates at a high angle of attack, at which drag plays a major role in creating the thrust of the sail. There is virtually no drift force.

Fordewind (Dutch voor de wind) - a course in which the wind is directed towards the stern of the ship.

Fordewind is the same “fair wind” that sailors desire, although in sailing this course is by no means the fastest, as one would expect. In addition, it requires attention and skill from the helmsman to control additional sails (usually a spinnaker). In this case, the sail is placed perpendicular to the direction of the wind, the thrust on it is created due to drag. Light wind on this course is practically not felt, since the speed of the apparent wind is equal to the difference between the speed of the true wind and the speed of the oncoming air flow.

A jibe is one of two turns (a turn is a change of tack) of a sailing vessel, in which the direction of the wind at the moment of the turn passes through the stern. Unlike a tack, a jibe is more complex and, at times, dangerous; it requires clear team actions when working with the sails. It is no coincidence that the command is given with the clarification: “Prepare for a jibe!”, whereas during a tack the commander simply commands, “Prepare for a turn!”

Tacking

Tacking a sailing ship. α - tack angle

A sailboat cannot sail directly against the wind. If it is necessary to get to any point located to windward, then tacking is used - moving towards the target on a close-hauled course on alternating tacks. To change tack you must make a turn.

If, while maintaining the tack, you need to go at a sharper angle to the direction of the wind, then they say that you need to “bring to the wind.” If, on the contrary, you need to increase the angle between the direction of the wind and the boat’s DP, then they say that it is necessary to “fall into the wind.” (It should, however, be remembered that “the wind blows into the compass,” that is, its directions are given not by where the wind is blowing, but from where. This means that if the ship’s course is, for example, north and the wind is from north, it is not blowing along the way, but towards the ship.)

In order to set the sail at the optimal angle of attack during these maneuvers, it must be pulled towards the DP - “select”, or released - “hauled”. Yachtsmen use these terms for all manipulations with gear - sheets, guys, etc.

Depending on the side from which the wind is blowing, courses relative to the wind can be starboard or port tack.

With a heading wind angle equal to 26 points, the close-hauled starboard tack in the sailing fleet was sometimes called starboard, and the left tack (wind heading angle of 6 points) was called a backboard. To clarify the course relative to the wind, the following expressions were used: “the ship is sailing on a starboard tack of 7 points to the wind” (that is, close-hauled at a heading wind angle of 78°); “The ship is sailing backstay on a starboard tack of 10 points” (that is, the heading angle of the wind is 112°); “The ship is heading fuller than 6 points” (that is, the backstay at a heading angle of 12 points, or 135°). The concept of “close-hauled” is also used as the sharpest course relative to the wind, at which a sailing ship can move forward (it ranges from 3 to 6 points 33.3/4° to 67.1/2°); steep and full backstay (up to 12 points and more than 12 points, or up to 135 ° and more than 135 °, respectively).

Calculation of the ship's path using known compass values. wind direction, course relative to the wind, compass corrections and drift called. in the sailing fleet by correcting bearings.

Ship's heading relative to the wind- the angle between the direction of the wind and the center plane (DP) of the vessel, that is, the heading angle to the point on the horizon from where the wind blows, expressed in angular degrees or points. Depending on which side the wind is blowing from, a distinction is made between starboard and port tack courses. Wind courses have their own names:

Leventik

• Leventik(fr. le vent) - a position when the wind blows almost directly in front of the ship. A sailing ship cannot sail against the wind, so “leftward” is not a course; it is correct to say “leftward position.”

Fordewind

• Fordewind(Dutch voor de wind), or downwind - a course in which the wind is directed towards the stern of the ship. A ship going into a gybe is said to be “going with full wind.” The angle between the wind direction and the center plane of the vessel in this case is about 180°.

Fordewind is the same “fair wind” that sailors desire, although in sailing this course is by no means the fastest, as one would expect. In addition, it requires attention and skill from the helmsman to control additional sails (usually a spinnaker). In this case, the sail is placed perpendicular to the direction of the wind, the thrust on it is created mainly due to the direct pressure of the wind on the sail. Light wind on this course is practically not felt, since the speed of the apparent wind is equal to the difference between the speed of the true wind and the speed of the oncoming air flow.

Gulfwind

Backstay

Beidewind

The best sailing ships sail at an angle of 30-35° to the direction of the apparent wind. Due to the addition of the vectors of wind speed and oncoming air flow, the speed of the apparent wind on a close-hauled course turns out to be maximum, as well as the lifting force on the sail, proportional to the square of the wind speed. The drift force also reaches its maximum value. If you try to sail at a sharper angle to the wind, the speed of the vessel will decrease, the sail will begin to flap, the lift will decrease and, finally, a moment will come when the drift and resistance of the water to movement will far exceed the thrust. The ship will lose speed.

Tacking

A sailing ship cannot sail directly against the wind. If it is necessary to get to any point located to windward, then tacking is used - moving towards the target on a close-hauled course on alternating tacks. To change tack you must make a turn. A distinction is also made between tacking in the wind, when a sailing vessel (usually a sailing catamaran or a dinghy skiff) follows a backstay course with a change of tacks, rather than a gybe course, to follow exactly with the wind. For high-speed sailing yachts, this method of reaching a leeward goal is faster.

There are two types of turns relative to the wind:

• Tack. In this maneuver, the bow of the sailing vessel crosses the wind line. The vessel is brought to the left, then falls on another tack, to the desired course. This maneuver is easier to perform on ships with oblique sails - Bermuda, gaff, lateen. For ships with straight sails, such a maneuver requires a very experienced and large crew. The sails need to be thrown onto the other tack in a certain sequence and strictly on time: the sails on the mizzen mast are brought to the wind first and help to bring it up. The sails on the foremast and, less critically, the mainmast are carried when passing through the wind line, and help to fall away. Otherwise, the ship may “miss the left,” lose speed and stop listening to the rudder.

• Jibe. During this maneuver, the wind line is crossed by the stern of the sailing ship. Thus, the wind is always fair and presents fewer difficulties for ships with square rigs. But for sailing yachts with an oblique rig, a change of tack is accompanied by a rapid (and, as a rule, for inexperienced crews, a sudden) transfer of sails from one tack to another. In this case, the spar and rigging experience a dynamic shock. Flying booms can either injure or throw unwary people overboard. To avoid such spontaneous turning, the sails are carried under control.

If, while maintaining the tack, you need to go at a sharper angle to the direction of the wind, then they say that you need to not turn, but “bring to the wind.” If, on the contrary, you need to increase the angle between the direction of the wind and the boat’s DP, then they say that it is necessary to “fall into the wind.” By changing the course relative to the wind, they simultaneously change the position of the sail in order to maintain the optimal angle of attack. To do this, it is necessary to pull him towards the DP - “select”, or release him - “poison”.

Depending on the side from which the wind is blowing, courses relative to the wind can be starboard or port tack.

With a heading wind angle equal to 26 points, the close-hauled starboard tack in the sailing fleet was sometimes called starboard, and the left tack (wind heading angle of 6 points) was called a backboard. To clarify the course relative to the wind, the following expressions were used: “the ship is sailing on a starboard tack of 7 points to the wind” (that is, close-hauled at a heading wind angle of 78°); “The ship is sailing backstay on a starboard tack of 10 points” (that is, the heading angle of the wind is 112°); “The ship is heading fuller than 6 points” (that is, the backstay at a heading angle of 12 points, or 135°). The concept of “close-hauled” is also used as the sharpest course relative to the wind, at which a sailing ship can move forward (it ranges from 3 to 6 points 33.3/4° to 67.1/2°); steep and full backstay (up to 12 points and more than 12 points, or up to 135 ° and more than 135 °, respectively).

Calculation of the ship's path based on known values ​​of the compass wind direction, course relative to the wind, compass corrections and drift is called in the sailing fleet correction of rhumbs.

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Notes

1. // Military Encyclopedia: [in 18 volumes] / ed. V. F. Novitsky I. V. Sytin, 1911-1915.
2. // Military Encyclopedia: [in 18 volumes] / ed. V. F. Novitsky [and others]. - St. Petersburg. ; [M.]: Type. t-va I.V. Sytin, 1911-1915.
3. // Encyclopedic Dictionary of Brockhaus and Efron: in 86 volumes (82 volumes and 4 additional). - St. Petersburg. , 1890-1907.
4. // Military Encyclopedia: [in 18 volumes] / ed. V. F. Novitsky [and others]. - St. Petersburg. ; [M.]: Type. t-va I.V. Sytin, 1911-1915.

Literature

• Marine encyclopedic reference book / N. N. Isanin. - Leningrad: Shipbuilding, 1986. - T. 1, 2. - 512, 520 p.
• Naval dictionary / V. N. Chernavin. - Moscow: Voenizdat, 1990. - 511 p. - ISBN 5-203-00174-X.

An excerpt characterizing the Course relative to the wind

In the first days of October, another envoy came to Kutuzov with a letter from Napoleon and a peace proposal, deceptively indicated from Moscow, while Napoleon was already not far ahead of Kutuzov, on the old Kaluga road. Kutuzov responded to this letter in the same way as to the first one sent with Lauriston: he said that there could be no talk of peace.
Soon after this, from the partisan detachment of Dorokhov, who went to the left of Tarutin, a report was received that troops had appeared in Fominskoye, that these troops consisted of the Broussier division and that this division, separated from other troops, could easily be exterminated. The soldiers and officers again demanded action. The staff generals, excited by the memory of the ease of victory at Tarutin, insisted to Kutuzov that Dorokhov’s proposal be implemented. Kutuzov did not consider any offensive necessary. What happened was the mean, what had to happen; A small detachment was sent to Fominskoye, which was supposed to attack Brusier.
By a strange coincidence, this appointment - the most difficult and most important, as it turned out later - was received by Dokhturov; that same modest, little Dokhturov, whom no one described to us as drawing up battle plans, flying in front of regiments, throwing crosses at batteries, etc., who was considered and called indecisive and uninsightful, but the same Dokhturov, whom during all Russian wars with the French, from Austerlitz until the thirteenth year, we find ourselves in charge wherever the situation is difficult. In Austerlitz, he remains the last at the Augest dam, gathering regiments, saving what he can, when everything is running and dying and not a single general is in the rearguard. He, sick with a fever, goes to Smolensk with twenty thousand to defend the city against the entire Napoleonic army. In Smolensk, as soon as he dozed off at the Molokhov Gate, in a paroxysm of fever, he was awakened by cannonade across Smolensk, and Smolensk held out all day. On Borodino Day, when Bagration was killed and the troops of our left flank were killed in a ratio of 9 to 1 and the entire force of the French artillery was sent there, no one else was sent, namely the indecisive and indiscernible Dokhturov, and Kutuzov hurries to correct his mistake when he sent there another. And small, quiet Dokhturov goes there, and Borodino is the best glory of the Russian army. And many heroes are described to us in poetry and prose, but almost not a word about Dokhturov.
Again Dokhturov is sent there to Fominskoye and from there to Maly Yaroslavets, to the place where the last battle with the French took place, and to the place from which, obviously, the death of the French already begins, and again many geniuses and heroes are described to us during this period of the campaign , but not a word about Dokhturov, or very little, or doubtful. This silence about Dokhturov most obviously proves his merits.
Naturally, for a person who does not understand the movement of a machine, when he sees its action, it seems that the most important part of this machine is that chip that accidentally fell into it and, interfering with its progress, flutters in it. A person who does not know the structure of the machine cannot understand that it is not this splinter that spoils and interferes with the work, but that small transmission gear that silently turns, is one of the most essential parts of the machine.
On October 10, the same day that Dokhturov walked half the road to Fominsky and stopped in the village of Aristov, preparing to exactly carry out the given order, the entire French army, in its convulsive movement, reached Murat’s position, as it seemed, in order to give The battle suddenly, for no reason, turned left onto the new Kaluga road and began to enter Fominskoye, in which Brusier had previously stood alone. Dokhturov at that time had under his command, in addition to Dorokhov, two small detachments of Figner and Seslavin.
On the evening of October 11, Seslavin arrived in Aristovo to his superiors with a captured French guardsman. The prisoner said that the troops that had entered Fominskoe today constituted the vanguard of the entire large army, that Napoleon was right there, that the entire army had already left Moscow for the fifth day. That same evening, a servant who came from Borovsk told how he saw a huge army entering the city. Cossacks from Dorokhov's detachment reported that they saw the French Guard walking along the road to Borovsk. From all this news it became obvious that where they thought they would find one division, there was now the entire French army, marching from Moscow in an unexpected direction - along the old Kaluga road. Dokhturov did not want to do anything, since it was not clear to him now what his responsibility was. He was ordered to attack Fominskoye. But in Fominskoe there had previously only been Broussier, now there was the entire French army. Ermolov wanted to act at his own discretion, but Dokhturov insisted that he needed to have an order from His Serene Highness. It was decided to send a report to headquarters.
For this purpose, an intelligent officer was elected, Bolkhovitinov, who, in addition to the written report, had to tell the whole matter in words. At twelve o'clock at night, Bolkhovitinov, having received an envelope and a verbal order, galloped, accompanied by a Cossack, with spare horses to the main headquarters.

The night was dark, warm, autumn. It had been raining for four days now. Having changed horses twice and galloping thirty miles along a muddy, sticky road in an hour and a half, Bolkhovitinov was in Letashevka at two o'clock in the morning. Having dismounted from the hut, on the fence of which there was a sign: “General Headquarters,” and abandoning his horse, he entered the dark vestibule.
- The general on duty, quickly! Very important! - he said to someone who was rising and snoring in the darkness of the entryway.
“We’ve been very unwell since the evening; we haven’t slept for three nights,” the orderly’s voice whispered intercessively. - You must wake up the captain first.
“Very important, from General Dokhturov,” said Bolkhovitinov, entering the open door he felt. The orderly walked ahead of him and began to wake someone up:
- Your honor, your honor - the courier.
- I'm sorry, what? from whom? – said someone’s sleepy voice.
– From Dokhturov and from Alexey Petrovich. “Napoleon is in Fominskoye,” said Bolkhovitinov, not seeing in the darkness who asked him, but by the sound of his voice, suggesting that it was not Konovnitsyn.
The awakened man yawned and stretched.
“I don’t want to wake him up,” he said, feeling something. - You're sick! Maybe so, rumors.
“Here’s the report,” said Bolkhovitinov, “I’ve been ordered to hand it over to the general on duty immediately.”
- Wait, I’ll light a fire. Where the hell do you always put it? – turning to the orderly, said the stretching man. It was Shcherbinin, Konovnitsyn's adjutant. “I found it, I found it,” he added.
The orderly was chopping the fire, Shcherbinin was feeling the candlestick.
“Oh, disgusting ones,” he said with disgust.
In the light of the sparks, Bolkhovitinov saw the young face of Shcherbinin with a candle and in the front corner a still sleeping man. It was Konovnitsyn.
When the brimstones lit up with a blue and then a red flame on the tinder, Shcherbinin lit a tallow candle, from the candlestick of which the Prussians ran, gnawing it, and examined the messenger. Bolkhovitinov was covered in dirt and, wiping himself with his sleeve, smeared it on his face.
-Who is informing? - said Shcherbinin, taking the envelope.
“The news is true,” said Bolkhovitinov. - And the prisoners, and the Cossacks, and the spies - they all unanimously show the same thing.
“There’s nothing to do, we have to wake him up,” said Shcherbinin, getting up and approaching a man in a nightcap, covered with an overcoat. - Pyotr Petrovich! - he said. Konovnitsyn did not move. - To the main headquarters! – he said, smiling, knowing that these words would probably wake him up. And indeed, the head in the nightcap rose immediately. On Konovnitsyn’s handsome, firm face, with feverishly inflamed cheeks, for a moment there remained the expression of dreams of a dream far from the present situation, but then suddenly he shuddered: his face took on its usually calm and firm expression.
- Well, what is it? From whom? – he asked slowly, but immediately, blinking from the light. Listening to the officer’s report, Konovnitsyn printed it out and read it. As soon as he had read it, he lowered his feet in woolen stockings onto the earthen floor and began to put on his shoes. Then he took off his cap and, combing his temples, put on his cap.
-Are you there soon? Let's go to the brightest.
Konovnitsyn immediately realized that the news brought was of great importance and that there was no time to delay. Whether it was good or bad, he did not think or ask himself. He wasn't interested. He looked at the whole matter of war not with his mind, not with reasoning, but with something else. There was a deep, unspoken conviction in his soul that everything would be fine; but that you don’t need to believe this, and especially don’t say this, but just do your job. And he did this work, giving it all his strength.

Yacht's course relative to the wind (Rumb of sailing)

Steep close-hauled (tacking). When a boat sails on a course as close (as possible) to the direction against the wind without lapping the luff, it is said to be sailing close-hauled. Sails should be chosen as strong as possible.

Full close-hauled. With this course, the yacht tacks less. The wind does not blow straight towards or towards the stern, but into the side of the boat, so the sails should be slightly trimmed compared to a steep close-hauled wind. as much as possible until they begin to rinse.

Gulfwind. A yacht moving under sail at right angles to the wind is said to be tacking. Since the wind is blowing on board, the sails are trimmed about halfway.

Backstay. When the wind is blowing from behind, but not directly astern, the yacht heads backstay. The sails are etched until the luff begins to rinse, and then they are selected to a sufficient extent for it to disappear. In this position the wind is coming from the stern and the spinnaker can be raised.

Fordewind. With a fair wind, the sails are completely trimmed. They are spread out to catch as much wind as possible, the yacht goes with the wind. When the wind blows directly astern, the jib can flutter because it is blocked by the mainsail. In this case, you can either put it on the other side, where it will fill with wind again, or lower it and install a spinnaker instead. (Large parachute-shaped spinnakers can only be used in a tailwind.)

Trimming the sail

The clew must keep an eye on the sails at all times - they must be set so that the yacht can show its best qualities. This means constantly watching and adjusting the leading edge of each sail. Every time a yacht changes course, the sails must be re-set and adjusted to ensure they perform at their best. Likewise, their position must be changed in accordance with each change in wind direction. If a sail luffs, the boat loses speed, so, especially in racing, a clew sailor must always be ready to trim the sails at the first sign of a luff luff.

In order for the yacht to tack when the wind is blowing to the windward side (moving against the wind), the sheets should be fully adjusted to reduce sloping, then the ship moves forward at maximum speed.

The position of the sail should be changed smoothly, in accordance with any change in course. When the ship moves away from the wind, the sails are trimmed during the turn so that on the new course they can be set as quickly as possible without rinsing. When the yacht is brought to windward, the sheets are pulled out during the turn to prevent any signs of lapping.

This way the yacht can maneuver at full speed all the time and both sails will work at their maximum.

Setting sails on a dinghy

Small dinghies can improve their seaworthiness on various sailing courses by using a centerboard.

When sailing into the wind, maximum lateral resistance is required, so the centerboard must be lowered completely. However, when the wind is blowing from behind (towards the stern), no lateral resistance is required, so the centerboard can be fully raised. In all intermediate positions, the centerboard should be installed in accordance with the course of movement.

Heading relative to the wind

Ship's heading relative to the wind- the angle between the direction of the wind and the center plane (DP) of the vessel, that is, the heading angle to the point on the horizon from where the wind blows, expressed in angular degrees or points. Depending on which side the wind is blowing from, the course of the starboard and port tacks is distinguished. Wind courses have their own names:

Leventik

• Leventik(fr. le vent) - a course that forms an angle of 0° with the wind direction, that is, the wind blows almost exactly in front of the ship in relation to the ship. Since a sailing ship cannot follow such a course, they usually say not “course”, but “left-hand position”.

Fordewind

• Fordewind(Dutch voor de wind) - a course in which the wind is directed towards the stern of the ship. A ship going into a gybe is said to be “going with full wind.” The angle between the wind direction and the center plane of the vessel in this case is about 180°.
  1. Fordewind is the same “fair wind” that sailors desire, although in sailing this course is by no means the fastest, as one would expect. In addition, it requires attention and skill from the helmsman to control additional sails (usually a spinnaker). In this case, the sail is placed perpendicular to the direction of the wind, the thrust on it is created mainly due to the direct pressure of the wind on the sail. Light wind on this course is practically not felt, since the speed of the apparent wind is equal to the difference between the speed of the true wind and the speed of the oncoming air flow.
  2. A jibe is one of two turns (a turn is a change of tack) of a sailing vessel, in which the direction of the wind at the moment of the turn passes through the stern. For ships with an oblique rig, a jibe, in contrast to a tack, is more complex and, at times, dangerous, requiring clear actions by the team when working with the sails. It is no coincidence that the command is given with the clarification: “Prepare for a jibe!”, whereas during a tack the captain simply commands, “Prepare for a turn!”

Gulfwind

• Gulfwind(Dutch halve wind), or half wind - a course at which the angle between the direction of the wind and the direction of movement of the vessel is about 8 points (about 90°). On this course, the wind blows perpendicular to the ship's port, and the apparent wind is directed from the bow at an acute angle to the ship's port. Accordingly, the sail is installed at a lower angle of attack, its thrust is equal to the longitudinal component of the lift force, and the drift force is equal to the transverse component. On this course, the sail should divide the angle between the DP and the direction of the apparent wind approximately in half.

Backstay

• Backstay(Dutch. bakstag) - a course that forms an angle with the direction of the wind of more than 8, but less than 16 points, that is, the wind blows from the back and side in relation to the ship. Highlight the course full backstay, at which the angle exceeds 135° degrees, that is, approaching jibe, and cool backstay(less than 135°). The sail is set at an angle to the wind. Usually on this course a sailing ship develops its highest speed. In the backstay, the sail operates at a high angle of attack, at which wind pressure plays a major role in creating the thrust of the sail. There is virtually no drift force.

Beidewind

• Beidewind(Dutch bij de wind) - a course at which the angle between the direction of the wind and the direction of movement of the vessel is less than 90° (less than 8 points). Close-hauled wind full And steep. Different sources draw the boundary between them in different ways (in the range from 45 to 67.5°). The thrust of a sail when close-hailed is entirely determined by its lifting force; with increasing wind pressure, the thrust force decreases, but the drift force increases. Thus, on this course the sail, installed with a minimum angle of attack to the apparent wind (5-10°), works completely like an aerodynamic wing.
  The best sailing ships sail at an angle of 30-35° to the direction of the true wind. Due to the addition of the wind speed vectors and the oncoming air flow, the apparent wind speed on a close-hauled course turns out to be maximum, as well as the lifting force on the sail, which is proportional to the square of the wind speed. The drift force also reaches its maximum value. If you try to sail at a sharper angle to the wind, the speed of the vessel will decrease, the sail will begin to flap, the lift will decrease and, finally, a moment will come when the drift and resistance of the water to movement will far exceed the thrust. The ship will lose speed.

Tacking

Tacking. α - tack angle

A sailboat cannot sail directly against the wind. If it is necessary to get to any point located to windward, then tacking is used - moving towards the target on a close-hauled course on alternating tacks. To change tack you must make a turn.

There are two types of turns relative to the wind:

• Tack. In this maneuver, the bow of the sailing vessel crosses the wind line. The vessel is brought to the left, then falls on another tack, to the desired course. This maneuver is easier to perform on ships with oblique sails - Bermuda, gaff, lateen. For ships with straight sails, such a maneuver requires a very experienced and large crew. The sails need to be thrown onto the other tack in a certain sequence and strictly on time: the sails on the mizzen mast are brought to the wind first and help to bring it up. The sails on the foremast and, less critically, the mainmast are carried when passing through the wind line, and help to fall away. Otherwise, the ship may “miss the left,” lose speed and stop listening to the rudder.

• Jibe. During this maneuver, the wind line is crossed by the stern of the sailboat. Thus, the wind is always fair and presents fewer difficulties for ships with square rigs. But for sailboats with oblique rigs, a change of tack is accompanied by a rapid (and, as a rule, for inexperienced crews, sudden) transfer of sails from one tack to another. In this case, the spar and rigging experience a dynamic shock. Flying booms can either injure or throw unwary people overboard. To avoid such spontaneous turning, the sails are carried under control.

If, while maintaining the tack, you need to go at a sharper angle to the direction of the wind, then they say that you need to not turn, but “bring to the wind.” If, on the contrary, you need to increase the angle between the direction of the wind and the boat’s DP, then they say that it is necessary to “fall into the wind.” By changing the course relative to the wind, they simultaneously change the position of the sail in order to maintain the optimal angle of attack. To do this, it is necessary to pull him towards the DP - “select”, or release him - “poison”.

Depending on the side from which the wind is blowing, courses relative to the wind can be starboard or port tack.

With a heading wind angle equal to 26 points, the close-hauled starboard tack in the sailing fleet was sometimes called starboard, and the left tack (wind heading angle of 6 points) was called a backboard. To clarify the course relative to the wind, the following expressions were used: “the ship is sailing on a starboard tack of 7 points to the wind” (that is, close-hauled at a heading wind angle of 78°); “The ship is sailing backstay on a starboard tack of 10 points” (that is, the heading angle of the wind is 112°); “The ship is heading fuller than 6 points” (that is, the backstay at a heading angle of 12 points, or 135°). The concept of “close-hauled” is also used as the sharpest course relative to the wind, at which a sailing ship can move forward (it ranges from 3 to 6 points 33.3/4° to 67.1/2°); steep and full backstay (up to 12 points and more than 12 points, or up to 135 ° and more than 135 °, respectively).

Calculation of the ship's path based on known values ​​of the compass wind direction, course relative to the wind, compass corrections and drift is called in the sailing fleet correction of rhumbs.

see also

Literature

• Marine encyclopedic reference book / N. N. Isanin. - Leningrad: Shipbuilding, 1986. - T. 1, 2. - 512, 520 p.
• Naval dictionary / V. N. Chernavin. - Moscow: Voenizdat, 1990. - 511 p. - ISBN 5-203-00174-Х

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Tacks, Full courses, Tacking, Apparent wind and...

Tack is the direction of movement relative to the wind, when the angle formed with the wind direction is greater than zero.

Accordingly, the starboard tack is the right foot or hand in front, that is, you always stand with your back to the wind, and movement to the right side is the starboard tack, to the left side is the left tack. Depending on the magnitude of this angle, the course relative to the wind line can be sharp or full.

• Leventik (le vent)- the position of the vessel relative to the wind, when the angle to the wind line is about zero. Since a sailing ship cannot follow such a course, they usually say not “course”, but “left-hand position”.
• Beidewind (bij de wind)- a sharp course relative to the wind line, when the wind blows at an angle from 0 to 80°. There can be a steep close-hauled wind (up to 50°) or a full close-hauled wind (from 50 to 80°).

Full courses are considered when the wind blows at an angle close to 90° or at an obtuse angle to the direction of movement. These courses include:

• Gulfwind (halve wind), or half-wind - the wind blows at an angle from 80° to 100°.
• Backstay (bakstag)- the wind blows at an angle from 100 to 150° (steep backstay) and from 150° to 170° (full backstay).
• Fordewind- the same “fair wind” that sailors wish for, although in sailing this course is by no means the fastest, as one would expect. The wind blows aft at an angle from 170° on one side to 170° on the other side.

Tacking.
You cannot go directly against the wind. If it is necessary to get to any point located higher upwind, then tacking is used, moving towards the target on a close-hauled course - on alternating tacks. To change tack you must make a turn. Also remember that with any course you drift (merge) a little with the wind, so you cannot clearly set the direction of movement to the point, you must always take a course a little higher into the wind, that is, with a margin.

Determining wind directions relative to you.

• Windward side– when you stand with your back to the wind, then the windward side will be your back, respectively, the windward side of the board where the heels are.
• Leeward side– on the contrary, it is everything that is in front of you (downwind) when you stand with your back to the wind. The leeward side is where your toes sit on the board.

Apparent Wind.
The apparent wind speed is the geometric sum of the speeds of the true wind and the wind caused by the yacht's movement (heading wind). If the speed of movement through the water is 1 m/s, then the speed of the induced wind is 1 m/s in the direction towards the bow. The faster the athlete moves, the stronger the induced wind, and - accordingly, the stronger the apparent wind. It also gets stronger if you go into the true wind (against the wind).