Anchorage. Organization of safe anchorage. Calculation of emergency anchorage when anchoring. Where d max is the maximum draft of the vessel

Whether you're stopping for lunch, looking for a cove to spend the night, or trying to keep your yacht from getting demolished... Either way, you need to anchor, safely and securely. And even if you always return to the pier when the sun sets, remember: the anchor is a “strategic weapon” in the arsenal of safety equipment on board. If the depth allows, many difficult situations can be stabilized by simply releasing the anchor, which will give you time to deal with the problem. Even in deep water, simply lowering the anchor into the water can reduce drift or keep the boat pointing toward the wind. Therefore, in the RYA Yachtmaster exam you will definitely be asked to anchor the boat somewhere. And rest assured that the location will be chosen so that the position can be easily checked using alignments or bearings to coastal objects or noticeable landmarks. Today, many shipyards include in the standard specification of a yacht an anchor of minimum weight, which can be used without violating safety requirements. This anchor is cheaper and takes up less space. If you intend to anchor frequently or plan to operate the boat in waters with strong currents, it makes sense to make an “upgrade” by increasing the length and gauge of the chain and choosing an anchor of greater weight.

HOW IT WORKS

The vessel's anchor device includes an anchor of suitable weight and a chain (or cable) of the appropriate caliber and length. A winch is installed at the bow (and/or stern), capable of pulling a decent weight of anchor and chain, although on small boats this is done manually. However, the effect of the anchor device depends not only on the mass and design of the anchor - the weight of the etched chain (cable) is also important. The chain provides a horizontal application of force to the anchor and, in addition, acts as a shock absorber. The holding force of an anchor depends on various factors: the nature of the soil, the mass and design of the anchor and its position on the bottom. The anchor has maximum holding force if its spindle lies on the ground and the chain approaches the anchor horizontally. Otherwise, as the load increases, the anchor rope becomes tense and the anchor may break. In addition, the part of the chain lying on the ground has its own holding force, therefore, to ensure safe parking, you should give enough chain so that it partially lies on the ground.

PREPARATION FOR ANCHORING

When preparing for anchorage, you should first of all carefully study the map - and not only with the aim of looking at a nice bay. You definitely need to understand what the bottom is like in this place (the Table shows the designations for Admiralty maps. - MBY). Any anchorage, except perhaps a short stop in favorable conditions, requires the release of the anchor. It must, firstly, catch on and, secondly, hold. The first does not always work out right away if, for example, there is seaweed, gravel or hard sand at the bottom. But even once hooked, an anchor in such soil can “crawl” unnoticeably, and drift the vessel will not be detected immediately.

Clay soils have the greatest holding capacity. However, during long-term mooring, the anchor and part of the chain lying on the bottom may sink into the ground, and then it will not be easy to remove the anchor. The most favorable are silty or silty-sandy soils, in which the anchor immediately picks up and holds well. When you're about to drop anchor on rocky, rocky, or shell bottoms, consider whether you're prepared to have a restless night or, worse, lose your anchor. The holding force of the anchor on such soils is equal only to the mass of it and the chain lying on the bottom. And even if you took the anchor, it’s too early to rejoice: it could get stuck in a crevice, from where it would be extremely difficult, if not impossible, to pull it out. A flat bottom is always better than sharply changing depths, where it is easy to miss the right “step” and drop the anchor to too great a depth (if it still gets stuck there, you can say goodbye to it forever).

FINDING A SUITABLE PLACE

In addition to a favorable bottom, navigational safety is important. If possible, parking should be chosen in places protected from prevailing winds, currents and sea waves. If you see other boats at anchor in the intended place, they will serve as a clue to how your yacht will land and what will happen to it. True, it is worth remembering that Various types ships under the same conditions may behave differently. If you are going to spend quite a long time at anchor, you need to know not only the direction of the wind at the moment, but also the forecast for its change. If the wind tends to change direction, then the advantageous situation when you are currently in a protected place may change: the wind will begin to blow in the direction of the shore, rocking will begin, and if the anchor also “crawls,” you will be dragged ashore. Therefore, when choosing a place, check the forecast for wind direction and strength (see Fig. 1). It may be better to change the location immediately or, in any case, develop a safe escape plan if the parking becomes uncomfortable.

LET'S RELEASE ANCHOR

To release the anchor, engage the anchor winch, releasing all locking devices (if your boat does not have a manual release of the anchor). Then turn the boat to face the wind or the current, whichever has more influence (remember that other boats at anchor are a good clue), and stop: we want zero speed relative to the bottom. When you are sure the boat has stopped, you can release the anchor using the down button/switch for a controlled release of the anchor, or simply release the stopper so that the anchor falls freely to the bottom under its own weight.

HOW MUCH CHAIN ​​TO ETCH?

It is necessary to know exactly the depth in the parking area: this determines how much chain needs to be removed.

Vibration of the anchor chain usually means that the anchor is “creeping” and the setting must be done again

The usual recommendation is four depths if you have an anchor chain, and six depths if you use a chain and cable combination (see Figure 2). Marking the circuit at regular intervals using colored cord - good way know exactly how many meters you have already released. If there is no marking, you can measure how many seconds it takes approximately one meter to “go”, and then calculate the time required to etch the required length. It is important that the anchor reaches the bottom before you begin to reverse, but you should not allow the chain to lie in a heap on the bottom (see Figure 2). For an overnight stay, you can put out more chain to sleep more peacefully, but don’t forget: with a long chain, the yacht “drives” along a much longer trajectory, which is unacceptable if there are many ships in the bay. In tidal waters, calculating chain length is more difficult because you have to take into account how the depth will change while you are at anchor. If you want to stay at anchor all night, you must take into account the full tide cycle. So, continue to release the chain while the boat is being pulled back by the wind and/or current. In calm conditions and without a current, you may have to “push” the boat back a little, briefly and discretely operating the throttle/reverse handle (see Fig. 3).

Once you have loosened enough of the anchor chain, carefully back up a little more to make sure the anchor is hooked and holding. If this happened, you will see how the chain is stretched. On many motor boats The anchor device is practically invisible from the control station, so assistance from the crew may be required at this stage. If you see or feel vibration in the chain, this is usually a sign that the anchor is creeping and will need to be re-anchored.

LET'S CHECK HOW IT HOLDS

To further understand whether the boat is being carried away, you will need suitable landmarks (see Fig. 4). Usually, when at anchor, the wind evenly “drives” the boat in an arc. To evaluate this movement, you need to notice the targets on the shore (along the side and along the course - this way you will quickly understand if something has suddenly changed). If the wind or current changes direction, new alignments should be selected. In addition, most modern chartplotters have an Anchor Watch feature: if there is drift, the device will notify you when your coordinates are outside the boundaries of a specified circle. If there are many other ships at the anchorage besides you or the bottom is not clean, you should use a buoy (see insert to Fig. 4). A rope attached to the anchor will allow you to tear the anchor off the ground if it gets stuck. When you are sure that the anchor is holding, good practice- remove the load from the winch: they are not always designed to hold the entire weight of the vessel for a long time. Either use a stopper or use a hook or rope threaded through a chain link to transfer the load to the nearest suitable cleat.

REMOVING ANCHOR

If you were anchored long enough, your boat could be mishandled or even blown away. Therefore, when you are going to raise the anchor, send one of the crew to the bow to clarify the direction of the chain. Move slowly forward along the chain towards the anchor so that the winch simply retrieves the chain rather than pulling the boat forward. Depending on how your yacht is equipped, you can operate the winch from the helm station or directly from the bow; If you entrust the latter to someone on the team, make sure that you use the same conditional signals and act in a coordinated manner. A chain going vertically down from the bow is a sign that the ship is above the anchor. If you can’t lift it, stop the chain and move forward slightly: this will pull out the anchor if it doesn’t lie well. When the anchor is raised and secured, the anchor winch control should be turned off to prevent anyone from accidentally releasing the anchor. In the next issue we will look at the Man Overboard situation.

Anchor and mooring operations.

Selecting a location anchorage determined by its goals, duration, hydrometeorological conditions and the condition of the vessel itself.

In an internal roadstead, the vessel is anchored in a strictly defined place at the direction of the pilot or in accordance with the rules of the port and, therefore, the navigator is not given the opportunity to choose an anchorage location.

Anchorage locations in the outer roadsteads of large seaports are usually indicated in sailing directions and on maps. In this case, the responsibility of the navigator is reduced only to the choice of a place to release the anchor at the specified anchorage, which must be done taking into account the free water area of ​​the roadstead and possible changes the position of the vessel in the event of a change in the direction and strength of the wind or current.

Significantly broader requirements for the choice of anchorage should be imposed in cases where anchoring is carried out for long-term stay in large roadsteads or in individual bays.

Such parking should be located in places that are, if possible, protected from prevailing winds and currents, and be safe from a navigational point of view. Particular attention should be paid to the nature of the soil and bottom topography.

Clay soils have the greatest holding capacity. However, during long-term parking, it is possible that such soil will “suck in” the anchor and the part of the anchor chain lying on the ground, which will create significant difficulties when shooting from the anchor. Therefore, the most favorable soils for anchoring are considered to be silty soils, silt with sand, which have satisfactory holding capacity and in which anchors can be easily picked up right away. Sandy soil and gravel hold anchors worse. Anchors in such soils can creep smoothly, which makes it impossible to immediately detect the ship's drift.

It is extremely undesirable to anchor on rocky or shell soil. On such soils, the holding force of the anchor will be equal only to its mass and the mass of the chain lying on the ground. In addition, on rocky ground, the anchor can get caught in a crevice, which will either lead to the loss of the anchor and part of the anchor chain, or, at best, will make shooting from the anchor very difficult and time-consuming. A flat and level bottom is always better than one with sharply changing depths.

The location of the proposed anchorage should be carefully studied according to the directions and port rules.

When approaching the anchorage site, it is necessary to translate in advance main engine to work in maneuvering mode, check the operation of the engine telegraph and the connection between the engine room and the bridge, check the readings of the ship's clock on the bridge and in engine room, notify the watch in the engine room about the expected time of anchoring the vessel.

15-20 minutes before approaching the anchorage site, crew members are called to their places and, according to the schedule, must take part in anchoring the vessel.

Immediately before setting, the operation of the windlass at idle speed and the position of the anchor chains in the chain box are checked, and the fairlead caps leading to the chain box are removed.

After a long sea voyage, it is recommended to first weigh the anchor down to the water with a windlass. In the future, they act depending on the depth at which the anchor will be released. When anchoring at shallow depths (up to 25-30 m), after checking the operation of the windlass (harnessing the anchor), clamp the band stopper, release all the other stoppers and disconnect the anchor chain sprockets from the windlass motor. If the depth at the anchorage site exceeds the specified value, the anchor chain sprocket of the released anchor remains connected to the windlass.

When anchored in daytime the black ball is being prepared for the rise, and at night the anchor lights are turned on.

The safety of an anchorage depends on a combination of a number of factors: the condition of the vessel, the nature of the soil and, first of all, the hydrometeorological situation.

Influenced external factors(wind, current) a ship at anchor can turn around on the anchor rope or move in a circle described around the anchor with a radius

R I = x + L max (10.1)

where x , - horizontal projection of the etched anchor rope, m Lmax - maximum length of the vessel, m.

When preliminary determining the radius of the anchorage, it is necessary to take into account that it may be necessary to extend the anchor rope over the entire length ℓ Ya.Ts, and also to provide a reserve ∆ℓ in case of drift and maneuvering when shooting from the anchor. Then:

X = √ ℓ 2 J.Ts – H 2 KL; where HCL is the elevation of the hawse above the ground, m

R I = √ ℓ 2 Ya.Ts – H 2 KL + L max + ℓ Ya.Ts (10.2)

The area of ​​a circle limited by radius R R is called the anchor place vessel moorings . It should be located away from: guidance lines, fairways, submarine cables and other vessels. The minimum depth here should be such that during low tide and when rocking in waves, the ship cannot touch the ground or its anchor lying on the ground.

You should always remember that even the most favorable anchorage, if a certain change in hydrometeorological conditions occurs, may turn out to be unsafe and immediate unanchoring will be required to change the anchorage location or go out to the open sea.

In this regard, it is strictly forbidden to carry out any work in the engine room while the vessel is at anchor that would involve disabling the main engine, steering and anchor devices. The vehicle must be in readiness, the period of which is set by the captain of the vessel depending on the specific situation. During the entire stay of the vessel at anchor, navigational watches are established both on the bridge and in the engine room.

The watch service must conduct continuous monitoring of both weather conditions and the surrounding environment, and the behavior of other ships anchored nearby. Much attention should be paid to the timely detection of ship drift, for which all methods available in this case should be used.

Currently, control over the drift of a vessel is most often carried out by navigation methods by taking control bearings or distances, or using GPS.

To achieve the greatest control efficiency, as reference points when taking bearings or measuring distances, you should select objects whose changes in bearings (distance) in the event of drift will be most noticeable. When selecting landmarks, it is necessary to keep in mind that it is not at all necessary that they be plotted on the map, since drift detection can be established by the nature of the change in bearings (distances) without making observations.

For direction finding, it is most advantageous to choose landmarks located close to the beam on both sides of the vessel, and for measuring distances - at the bow or stern heading angles.

Particular attention should be paid to monitoring the drift of the vessel when anchored on poorly holding soils, with an uneven hilly bottom. In this case, in addition to monitoring the drift of the vessel on the bridge, it is recommended to post an observer on the bow directly at the anchor device. A sharp change in the tension of the anchor chain, when it is polished, and then immediately sag sharply, is a sign that the anchor is creeping along the ground. Having a watchman at the windlass, if there is no automatic anchor release device, is also useful when anchored in a roadstead with big amount other ships at anchor. In the event of drifting of a neighboring vessel, quickly releasing the anchor chain will eliminate the risk of a pile-up or at least reduce its consequences.

Measures to prevent drift depend on the reasons that caused its occurrence. Under favorable weather conditions, ship drift can occur due to weak holding force of the anchor, when the anchor either creeps on poorly holding soils, or periodically turns out of the soil as a result of uneven compaction of the soil under the anchor's feet in loose soils.

In such cases, it is best to change the anchorage, especially if the drift occurs towards the shore, any navigational hazard or another vessel.

Most often, the cause of drift is the deterioration of the hydrometeorological situation.

It is quite clear that the ship's drift will become inevitable if external forces reach a value exceeding the holding force of the anchor. Within certain limits, the holding force of the anchor can be slightly increased due to additional etching of the anchor chain. The part of the chain lying on the ground allows you to increase the holding force of the anchor by the amount:

∆R YAK = fр C∆ℓ (10.3)

Where f- coefficient of friction of the anchor chain on the ground;

p C - weight of 1 m of anchor chain in water, N;

∆ℓ is the length of the anchor chain lying on the ground, m.

In addition, this part of the chain will compensate for the jerks that inevitably occur when the wind increases, prevent the appearance of force that turns the anchor out of the ground and, therefore, make the anchorage calmer and more reliable. If there is a sufficient reserve, it is recommended to additionally extend the anchor chain when the wind increases to 6-7 points from half the initially etched length at medium depths to double at shallow depths. To ensure that when the anchor chain is being picked up, the ship does not accelerate and the chain does not get tense with a jerk, the pickling must be done in small sections of 5-6 m, starting at the moment when the anchor chain, after the next jerk, begins to get slack.

After each retrieval, the anchor chain must be secured. At the same time, the second anchor should be prepared for release.

With a further increase in wind (up to 8 points), the anchor chain is poisoned almost to the chewing tack, and the main engine is put into immediate readiness. If Taken measures do not give the desired effect, then they begin to carefully work on the machine, the operating mode of which must be set in such a way that the ship does not acquire forward motion and the anchor chain does not go under the hull.

The reliability of anchorage sharply deteriorates if, with increasing wind, the ship begins to yaw, that is, to make oscillatory movements in one direction or the other from the line of action of the wind (Fig. 12.6). The appearance of yaw is caused by the fact that the ship's anchor fairleads are usually located outside its center plane. As a result, when the ship is anchored at the same anchor, the force of wind pressure and the tension force of the anchor chain will be applied in different vertical planes and will create a pair of forces that will tend to turn the ship at a certain angle q so that these forces (Rya And F a) steel in one vertical plane.

In general, the safety of an anchorage can be described by two formulas:

· The holding force of the anchor device must be equal to or greater than the sum of the external forces acting on the vessel;

R YAU ≥ ∑F (10.4)

· The minimum depth at the anchorage site must be no less than

Hm ≥ 1.2 d max + 0.7 h V (10.5)

Where d max is the maximum draft of the vessel;

h B - maximum wave height in a given area and season:

At sea depths exceeding 2/3 ℓ Y.Ts, anchoring is not advisable.

Choosing an anchorage along with a suitable mooring device is critical to a good night's sleep. But not all bays allow you to anchor without much thought and preparation. We will show you how to correctly “read” sea charts, and what needs to be done in advance to be sure of the safety and comfort of anchorage.

Forward - to new bays

You won't find a better anchorage! A lonely island with a steep coast that protects from the gusty south-east wind. Many ships seek shelter from the wind on the leeward side of the island and anchor in the sandy bottom. Only a few leave the anchorage again in the late afternoon to return to the port and spend the night there. It happens as it should happen: at night a thunderstorm front approaches the anchorage. The wind changes to the west, it begins to rain, and the boats, under strong gusts of wind and increasing roughness of the sea, are increasingly breaking from their anchor chains. There is a risk of being washed up on the leeward shore; on some yachts the anchor breaks out of the ground and begins to drift away; others let the anchor chain go a little by turning on the engine. In 20 minutes the front passes. Silence reigns again on the small island in the Baltic Sea.

Was the anchorage location ultimately chosen correctly? There are not many sheltered bays that provide sufficient protection for any change in wind direction. Most often, bays are not protected on one side. You should always remember that the wind direction can change suddenly, and when choosing an anchorage this fact must be constantly taken into account. Somewhere nearby there could very well be a wooded shore that would provide protection in the westerly wind. Safe harbor in close proximity. Thorough preliminary work with the map, of course, will not allow you to avoid all problems associated with changing weather conditions, but it will allow you to better respond to unexpected, most often local, weather changes.

Choosing the right anchorage begins with studying paper navigation charts. Digital navigation charts on the small display of a chart plotter are less useful because the surrounding conditions of the desired anchorage can only be viewed by scrolling. A paper navigation map, on the contrary, gives detailed review both the actual place of interest and the surrounding area. Along with information about fairway markings and grading lines, it provides insight into the topographical details of the shoreline that should be taken into account when choosing an anchorage.

Card 1 (INT 1) of the German Federal Office Marine Shipping and Hydrography (BSH) provides information on symbols, abbreviations and terms on official nautical charts. For example, she explains the pictograms that indicate rocky coastlines, wooded areas, steep banks, and even houses on navigation maps.

After a little training, looking at the navigation map, an idea of ​​the chosen anchorage is already formed in your head. On the following pages we will present to you a number of anchorages on the coast of the North and Baltic Seas and show what details in the navigation charts will allow you to make a conclusion about the security of the anchorage.

Working with maps

Navigation charts depict specific details not only of the water surface, but also of the coast. For ships at anchor, information such as forest cover or relief is interesting. Information about the shore is also important. Yachts anchored off a steep shore are more protected than those anchored on a flat spit, while rocky coastlines often suggest that the seabed will also be rocky.

Well protected bays

Bays protected on all sides- rare and favorite shelters to wait out the storm. Ideally, their diameter does not exceed one to two nautical miles, and the only narrow entrance to them ensures that the free wave of the open sea does not find its way into the bay. In the Baltic Sea, the coastal zone of these bays is most often surrounded by forest and has small hills that provide good protection even in strong winds.

If you anchor not too close to the shore, then in small bays of this type even unexpected changes in wind direction can be neglected. However, you should constantly check whether the anchor is still holding. In the northern part of the strait Als Sund the bay is located Dyvig, which is highly rated as an anchorage spot.

Why is it so popular among Danish yachtsmen? The entrance at the southern end of the bay is narrow and only visible just before entering the bay. In addition, immediately after its entrance, the bay turns sharply to the north in such a way that the free wave of the open sea, which enters from the west, cannot greatly interfere with yachts at anchor. The banks are covered with forest and offer sufficient protection on all sides in case of headwinds. An isobath of two meters runs parallel to it at a short distance from the shore and thus prevents yachts from drifting away when the wind direction changes towards the shore slope. If things get really rough, both small harbors at the northern end of the bay can be used as an alternative for anchoring.

“The narrow passage is a typical sign of such a safe bay on all sides.”

The bay is also well protected Helnaes, lying southwest of the island Funen (F?nen), with the same characteristics, but much larger. The bay is protected from the west by a large peninsula, while three smaller islands fence off the bay from the south. The bay offers a wide variety of anchorages and there is a calm spot in any wind direction. Of course, if the wind direction changes, it should be changed.

According to the map, The banks are densely forested and provide some basic protection. In case of strong westerly winds, you can find protection on the leeward side of the peninsula. Not only because the shore is hidden there too dense forest, but also because the small dot on the map symbolizes that the anchorage is protected by a hill. The height mark runs on the map in close proximity to the coastline, so that the coast goes up quite steeply for more than 20 meters. Such areas are distributed throughout the bay and promise good protection when the wind direction changes.

Fjords

During the last ice age, huge glaciers covered large parts of the north. On their way to the lower regions of the modern Baltic Sea, gigantic masses of ice burrowed into the landscape and left behind kilometer-long furrows on today's coast. These narrow sea bays often offer excellent anchorage conditions, as nature itself has made them protected.

In Schlei, one of the narrowest fjords, anchoring opportunities are presented one after another. When weather conditions change, ships can use another bay. Due to the narrowness of the fjords, a strong wave can neither form here nor penetrate from the outside: natural sandbanks that formed at the confluence with the Baltic Sea prevent waves from entering the strait Belt. When there is a strong westerly wind, shoals can form in larger, semicircular bays called noors.

Strong currents or changes in water levels may occur in strong winds of force 6 Beaufort, but this is rare. In both bays to the south and north of the harbor, shown on the fragment of the map, you can easily find a place to anchor.

If weather conditions change, you must look for another parking place. It's rare to be truly unpleasant here. But if, nevertheless, the water level changes noticeably, to be on the safe side, you should move to a nearby harbor.

Islands with crescent spits

When crossing the islands of the Danish South Sea, the most common type of anchor bay is crescent bay, which is not protected on one side. Most often we are talking about a flat spit, which protects the anchorage area, at least from free waves. Since these spits are mostly sand, they do not provide much protection from the wind, but have an excellent sandy bottom for anchoring. Bay near the island Avernako, shown in the photo, provides sufficient protection in westerly conditions and has a good seabed for anchoring thanks to the sand spit, which is marked with a dotted line.

Even if it is impossible for a wave to form in the bay, it can become uncomfortable in strong winds. To the north of the bay there is a steep coast and a hill, which provide an alternative in case of strong winds. This type of bay requires a little more attention as it needs to react to changes in wind direction. If the wind direction remains constant, these bays will provide a relaxing anchorage that will be a memorable voyage experience.

Wadden Sea/tidal zones

Wadden Sea- This is a one-of-a-kind natural landscape created by the changing tides, which are the reason for the daily change in the appearance of Watts. Frisian Islands, which stretch along the Dutch and German coasts, surround the Wadden Sea and protect the entrance channel from the partially unfavorable conditions of the North Sea. Constantly changing water levels and tidal currents require a high degree of attention and care from yachtsmen. However, not only does navigation in Watts require a lot of attention, anchoring also obeys different rules. However, if you follow some basic rules when choosing an anchorage, the Wadden Sea provides varied and, above all, well-protected anchorages.

Wadden Sea cut by natural channels: tides. They provide movement - water entering the watts and back. While some tides dry up at low tide, large tides reach a depth of four meters even at low tide. On nautical charts, the depth of the tidewater is indicated as LAT (Lowest Astronomical Tide) and denotes the lowest possible water level. Even during strong spring tides, this value is less than the value stated on the chart, so there is still a lot of water under the keel, an order of magnitude more than what is stated on the chart.

Since the Wadden Sea is a protected area, there are special traffic rules that are developed in accordance with government laws and land regulations. Compliance with these rules is mandatory in order not to cause great harm to the animal and plant world. The Union of Shallow Water Yachtsmen, representing the interests of those who sail on the North Sea coastline, has developed its own code of honor.

The main one is the provision that zone 1 marked on navigation charts is a territory in which anchoring is prohibited. This also applies to the marked fairway. Otherwise, anchoring in the Wadden Sea does not present any particular problems, so says Olaf Morgenstern, an experienced yachtsman who regularly anchors in the North Sea foreshore and also runs aground at low tide.

Even if shallow water yachtsmen choose an anchorage location most often intuitively, they also follow clear rules that can be clearly understood from the navigation chart and always be guided by them.

Since a lot of water flows through deep-sea tides, fast currents arise in them, while the soil is often very hard. In conditions when the wind blows against the current, rough seas begin, which prevents a restful anchorage: an unfavorable circumstance for a calm anchorage. Therefore, you should avoid deep-sea tides, which are easily recognized on navigation charts.

More suitable are shallow tides, which, even at low tide, provide a sufficient amount of water and also have soil with a slight rise towards the shallows.

Most often, the water there is much calmer, the current is not so strong, and the soil is mostly soft. If the wind direction changes, with a strong wind of 6 points on the Beaufort scale, these places will in any case lose their attractiveness. Some places offer complete comfort, since even at low tide they do not remain without water, so that there is always the desired palm-width of water under the keel.

In soft muddy soil the keel is buried a few more centimeters, thus preventing any unintentional capsizing of the boat. If the keel is still stuck in the mud, and at the last moment before low tide you want to start the engine and leave the anchorage, the best alternative is a cup of coffee, good book and waiting for the tide. “If you try with all your might to pull the ship out of the mud, the propeller can leave grooves up to two meters deep,” says Iris Bornhold, chairman of the union Soltwaters Wattseglervereinigung.

In the following sections we will introduce you to some of the places on the North Sea coastline and, using nautical chart information, show you what makes a good intertidal anchorage.

Code of honor Soltwaters Wattseglervereinigung for those who walk on the North Sea coastline

- Behave in the Wadden Sea...,

…it’s like you’re visiting Mother Nature. The Wadden Sea is an area where peace reigns. Take this into account in all your actions, avoid loud and fussy engine noise, unnecessary flapping of the sail, loud music on the radio.

- Feel your responsibility...

…for the behavior of others, especially your own team. Often harm is caused not intentionally, but out of ignorance. Along with his main responsibility to manage the yacht and crew, the skipper must familiarize his crew with the features and beauty of the Wadden Sea and orient their behavior in harmony with nature

- Don’t throw anything overboard...

…especially no cans or bottles, no plastic, no oils or paint residue. For household waste there are trash cans that can be found in any harbor

- Be respectful of restricted areas...

...there are a number of restricted areas, which are indicated on the corresponding navigation maps. They must protect sensitive plants and animal species of the Wadden Sea from possible disturbance, especially during egg hatching and mating season, respectively from 1.04 to 31.07. every year. Do not disturb seals or birds, even to photograph them. Seals are very curious by nature - they themselves come closer to the ship. And then using a long lens you can take impressive pictures.

Shallow tides with slight shoreline rise

Small tides which, even at low tide, are filled with water and provide the opportunity for anchoring, are more suitable than large and deep ones.

Since the current in these shallow flats is not particularly strong, there are no formations on the sides of the flats. steep slopes, but sloping, soft soil.

Such conditions promise a generally easy location on the North Sea coastline, which is flooded during high tides, with the added advantage of being elevated on the windward side.

As there are no great elevations in the Wad, and the highest are the flat sandbanks at low tide, despite the calm water there is no protection from the wind. However, if the parking place is chosen near one of the islands, you can find some protection from the wind.

Surrounded by small rises in the coastal strip

In the Wadden Sea it is rare, but still possible to find places for anchorage, similar to the bays of the Baltic Sea protected on all sides. Although these "bowls" are not surrounded by protective coastal formations, there are places surrounded by a slight rise in the shoreline and the depth there is sufficient even at low tide.

Since the slight rise of the coastline ensures that waves do not form and provides protection from the wind in almost all directions, such bays are an ideal alternative to crowded harbours. True, they are not easy to recognize on the map. Most often they branch off from a small tide and end at low tide at a slight rise in the shoreline.

Deeper tides

Even if deep tides are less suitable for anchorage, sometimes it becomes necessary to look for a more or less suitable place there. During the summer months, most island harbors are often hopelessly overcrowded. Anyone who, after a long day of sailing, approaches the harbor in the evening and realizes that it is completely clogged, has two alternatives: drop anchor somewhere nearby or sail for another couple of hours to the next harbor.

Since the last option is not always feasible due to the effects of tides, and the other harbor, perhaps, can also be occupied, only the first option remains open. The coastal zone of the Netherlands is dominated by large deep tides, which are ten meters deep even at low tide, so you have to look for a suitable anchorage there. Along the edges of the tide the current is much less, the tides run close to the land, so the island itself slightly protects the ship.

Of course, it quickly becomes so shallow beyond the fairway that you should anchor immediately behind the strip of buoys. Ideally, you will be able to find another small shallow area on the map. Although it can be uncomfortable in a “wind direction versus current direction” situation, the extended shallows along the edges of the tide trap a large free wave.

Practical advice

When anchored in Watts, always keep a spare anchor at the stern ready. If the bow anchor slips, you can quickly throw out the stern anchor, which will further prevent both chains from twisting. As the direction of water movement changes, the anchor should also be monitored and, if necessary, thrown out again.

When choosing an anchorage, one takes into account the depth, protection from wind and waves, the size of the anchorage area, the presence and characteristics of tidal phenomena, the bottom topography and the nature of the soil, the proximity of navigational hazards, the presence of landmarks, the condition and weather forecast, as well as the characteristics of the vessel and the expected duration of anchorage.

The size of the water area required for anchorage is approximately estimated by the radius R, calculated by the formula:

l is the length of the anchor rope required for safe anchorage, m;

H"- height of the anchor fairlead above the ground, m;

L- vessel length, m;

DR - distance margin, selected depending on specific conditions and circumstances, m.

Minimum depth H , providing safe parking, is calculated by the formula:

, Where

T is the maximum draft of the vessel, m;

h in - probable wave height for a given season in the anchorage area, m,

The safety of the anchorage is largely determined by the nature of the soil, on which the holding force of the anchor depends. Silty-sandy and clayey-sandy soils, as well as gravel and shell mixed with clay and silt, have good properties in this regard. By themselves, silt and clay strongly suck in anchors, which makes it difficult and sometimes impossible to tear them off the ground. Rocky soils made of boulders, large rocks or slabs are especially unfavorable for anchoring. On such soils, anchors do not hold well, and the ship, under the influence of wind or current, acquires a significant drift speed, which can lead to a break in the anchor chain if the anchor gets stuck in a crack or gets caught on a rock ledge.

Maneuvering during anchor operations.

When approaching an anchorage, the vessel's speed should be low in order to be able to absorb inertia and prevent a jerk when reaching the rope.

When the chain is freely etched after the anchor is released, even after clamping the tape stopper, the vessel has the opportunity to advance until the rope straightens a very short distance, amounting to 0.3-0.4 depths - with a length of the etched rope equal to 3-4 depths, i.e. one tenth of the length of the etched rope. Elastic extension of the anchor chain increases this distance by approximately another 2-3% of the chain length.

When the kinetic energy of a moving vessel is extinguished at a short distance, if the anchor picks up the ground and does not crawl, a strong jerk occurs.

When the speed of the ship doubles, the jerk force increases four times, i.e., in a quadratic relationship.

If the main engine operates in the direction of extinguishing inertia, then part of the kinetic energy of the vessel is compensated by the work of the propeller and the maximum jerk force at the same initial speed the vessel is reduced by an amount equal to approximately twice the propeller thrust. This very important circumstance must be used to avoid breaking the anchor chain or breaking the anchor if the ship’s speed exceeds the permissible value.

Permissible speeds are calculated taking into account the preservation of a double safety margin, i.e., taking into account the fact that the jerk force reaches half the breaking strength of the anchor chain.

In the calculations, the average values ​​of the power of the main engines, characteristic of ships of a given displacement when loaded, were taken, as well as the average calibers of the anchor chains. Therefore, taking into account that the weight of the anchor, and therefore the gauge of the chain, is selected for the vessel not only by displacement, but also taking into account the sail area, as well as possible deviations of power from the accepted average values.

For ships in ballast with displacements approximately half those listed in the table, permissible speeds increase by approximately 10-50%.

If anchoring is carried out on a single-screw vessel with a starboard rotation and a significant wind force, and the limited water area does not allow approaching the chosen anchorage site with the bow against the wind, maneuvering must be performed at a more or less significant speed in order to maintain controllability of the vessel and prevent large drift . In this case, it is recommended, if circumstances permit, to calculate the maneuver in such a way that when approaching the place where the anchor is released, the ship turns to the right.

It is known that in the first period after putting the rudder on board with the engine running forward, the ship loses speed no worse than after giving full reverse on a straight course. Therefore, even before reversing the engine, it is recommended to shift the rudder to the right side, and when the ship acquires sufficient angular speed, give full speed back, and then release the starboard anchor in the selected place.

Due to the significant drift angle on the circulation towards the outer side, the anchor chain will be pulled towards the stern at a significant angle to the DP. This will dramatically reduce the jerk force when the chain is delayed. When performing a similar maneuver with a turn to the left and the release of the left anchor, you need to take into account that after reversing the engine, the turn to the left quickly stops due to the lateral force of the propeller working in reverse. Therefore, a breakthrough may occur.

In any case, you need to hold the anchor chain smoothly so that the windlass sprocket can turn if the chain tension suddenly increases sharply. The tape stopper can be fully clamped only after the vessel has reached the rope and the inertia has been extinguished.

On dense silty and clayey soils, even small jerks that can tear the anchor out of the ground are extremely undesirable, since after this the anchor, stuck to the dense soil, does not pick up well, and the vessel may drift.

When anchoring in a current, it must be taken into account that the vessel, stationary relative to the water, continues to move relative to the ground at a current speed that can significantly exceed the permissible speed when anchoring. In this case, it is necessary to approach the place where the anchor is released as strictly as possible against the current, monitoring the actual speed by buoys, other vessels anchored, or coastal landmarks. If there are no reference points, you should first cut the chain to a length only slightly greater than the height of the fairlead above the ground, which will allow you to determine the direction of movement of the vessel relative to the ground by the tension of the rope and, if necessary, extinguish the inertia by operating the engine.

When anchoring at depths exceeding 25-30 m, as well as when releasing onto rocky ground, you must first release the anchor with a windlass to a height of about 5 m above the ground and only then release from the stopper band.

If an anchor placed on the ground is used to improve maneuverability and reduce drift when maneuvering at low speed in cramped conditions, then the length of the etched chain should be 1.5 times the height of the anchor fairlead above the ground. Under this condition, the chain makes an angle of approximately 45° with the ground, and since the maximum angle of deviation of the anchor legs from the spindle is approximately the same value, when pulling the anchor, its legs move parallel to the surface of the ground without burrowing into it.

When shooting from an anchor in significant wind or current, it should be taken into account that the vessel begins to drift even before the anchor leaves the ground. In this case, the anchor may get caught in the anchor chain of another vessel, and a pileup or dangerous drift towards shallow depths may occur. Therefore, it is necessary to use the main engine and rudder to hold the vessel in place until the anchor lifts off the ground.

When shooting from an anchor in a tight roadstead, it should be taken into account that the extension of the vessel when turning from a standstill at medium speed with the rudder on board is approximately two times less than the extension during circulation at a steady forward speed. If, due to lack of free space, there is no confidence in the success of the turn, then you should first turn the vessel with an anchor on the ground using the engine and rudder in the desired direction.

When maneuvering after unanchoring in cramped conditions on a single-screw vessel with a right-handed propeller, turns to the right, other things being equal, are usually safer than to the left, since, if necessary, you can reduce or extinguish the inertia by reversing without stopping the turn to the right.

The choice of anchorage location depends on its purpose. When a ship is laid up from a storm, only issues of ensuring the safety of the ship are taken into account. When anchoring a ship for loading and unloading operations and disembarking passengers, the ship is placed as close as possible to the port (shore) to ensure speedy unloading. In all cases, every precaution is taken for the safety of the vessel. If ships find themselves in an unprotected roadstead, they must change their anchorage depending on the weather and other factors.

For anchorage, depth, bottom topography, soil, and the size of the free water area of ​​the roadstead are important. Under the influence of changes in wind direction or current, an anchored vessel can move in a circle relative to the anchor. The radius of this circle is equal to the sum of the length of the vessel and the horizontal projection of the anchor chain. Therefore, the distance to the nearest danger should slightly exceed this radius.

When anchoring a vessel, the depth and changes in depths during the anchorage period are taken into account. The best depths for mooring ships with a draft of about 10 m are 15-30 m. For ships with a draft of about 6 m, 8-20 m are optimal. Minimum depth anchorage is determined by the empirical formula

where T is the draft of the vessel, m;

H is the highest wave height during parking, m;

0.6 - minimum water reserve under the keel, m.

When parking in an area affected by tidal currents, this calculation is made at the time of the highest low tide during the parking period.

Vessels in ballast and not fully laden require a more secure anchorage than vessels that are fully laden. This is explained by the fact that ships in ballast have greater windage and are more susceptible to wind. They yaw heavily at the anchor, which can break the anchor chain or cause the ship to drift. Favorable conditions for anchoring ships are considered to be good ground, wind not exceeding force 5, moderate waves and weak currents. The ground at the anchorage site should be as level as possible.

From the point of view of anchorage, soils can be divided into three groups. Good soils are considered to be clayey and silty soils with sand, soils with pebbles and shell rock; medium - pure clay and silt, sand, pebbles; bad soils - rocky.

The length of the anchor chain to be etched depends on the depth of the place, weather and the material from which the anchor chain is made. In Fig. 183 shows a graph of the dependence of the length of the anchor chain on the depth of the anchorage site. The graph is based on the formula

N - depth of the parking area, m.

The coefficient k for an anchor chain made of wrought iron is 25, for an anchor chain made of wrought iron - 27.5, for an anchor chain made of high tensile strength steel - 38.6.

During anchorage, the ship yaws under the influence of wind, current and waves. The most dangerous positions of the vessel are when the anchor-chain experiences the greatest tension. Particularly dangerous is the situation when the anchor-chain rests on the stem and experiences additional bending moments.

The tension of the anchor chain during yaw is summed up from the forces of wind, current and centrifugal force of inertia. The maximum additional voltage on the armature-chain from the action of inertia force during yaw can be determined by the formula

Rice. 183.

G - 9.81 - gravity acceleration, m/sec²;

L1 - horizontal distance from the anchor to the center of gravity of the vessel, m;

φ0 - yaw amplitude, degrees;

T0 - yaw period, sec.

After substitution known values we get

The yaw amplitude decreases if the angle between the direction of the current and the wind is close to 90°. To reduce yaw in fresh weather, it is necessary, if possible, to additionally etch the anchor-chain, the more the stronger the wind and the shallower the depth. With a wind of force 7 and medium depths, the anchor-chain is drawn out one and a half times more than in calm weather, and at shallow depths - twice as much.

To reduce the yaw of the anchor chain, when the chain rests on the stem, the rudder should be placed in the direction opposite to the given anchor. In moments of dangerous stress, it is recommended to release the anchor-chain or dampen the inertia by working the machines, but in such a way that the ship does not receive forward movement from the machines, because this will lead to more sharp jerks in the future.

When a vessel is moored in an open roadstead, it must be ready at any time to weigh anchor and go to sea.

When anchoring the vessel, the situation in the roadstead is taken into account. You should not approach the anchorage from the windward or current side of the anchored vessel or the danger. The approach to the anchorage site is carried out at low speed; depth is often determined; in particularly difficult cases, a boat is first sent to measure the depths.

Rice. 184.

Before releasing the anchor, the rudder brings the ship directly against the wind (currents, waves) and, having extinguished the inertia, allows the machines to move backward. As soon as the ship moves back, the anchor is released. In emergency situations and at high speeds, the anchor is released at low speed forward. With the simultaneous action of wind and current, it is taken into account that the wind has a stronger effect on unloaded ships with a large freeboard, and the current has a stronger effect on ships with a larger draft.

If, during the period of anchorage in a roadstead in a closed bay, waves appear that are not dangerous for the ship, but cause damage to the watercraft, the ship is set with a log to the waves or wind. To do this, through the stern bales of the side on the side opposite the unloading side, a cable (spring) is fed and secured to the anchor-chain. The anchor-chain is poisoned, and the ship becomes a log to the wind (Fig. 184, a).

When anchored on a spring, the vessel can be positioned at any angle to the wind or waves, but anchoring becomes more difficult and there is a danger of the spring winding around the propeller. When placed on the spring half-hull (Fig. 184, b), when the spring is brought in from the side hawse located in front of the superstructure, the ship gains greater maneuverability. The method of placing a vessel on a spring with the delivery of a rope or stop anchor (Fig. 184, c) is less reliable, since the rope can crawl. But this method is convenient in that the perlin can be easily released and you can immediately gain the ability to maneuver at anchor.

Placing on a barrel requires a number of preparatory measures and lowering the boat to secure the mooring line on the barrel. An anchor chain is used as a mooring line. It is not recommended to place several mooring lines on the barrel, since usually only one cable almost completely takes on the entire load, and the maneuver becomes much more complicated.

During anchorage, the watch service must constantly monitor the slightest changes in the situation in order to prevent an accident in time and get out of a dangerous situation. In the engine room and on the bridge, running watches are maintained, regardless of the duration of the stay and the conditions in the roadstead.

When anchoring a vessel with towed vessels, a significant extension of the convoy's circulation radius is taken into account. When the caravan enters the roadstead, the towing ropes are shortened to a minimum. The yaw of towed vessels is damped under the influence of the mass of the towing vehicle. The towed vessel is placed on its own anchor, since it creates an additional load on the anchor-chain of the towing vehicle and, in addition, the vessels may pile up on each other.

The maneuver for unmooring a vessel depends on the anchorage conditions and the reasons for leaving the anchorage site. In especially severe cases, to reduce the time of removing the vessel from the anchor, an anchor-chain is riveted and the anchor is left on the ground. In order to find the anchor later, a bright buoy is tied to it.

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