Vessel circulation and its elements. Quantification of the vessel's circulation What is the tactical diameter of the vessel's circulation

For a quantitative assessment of circulation, geometric and temporal-velocity characteristics are used.

The geometric characteristics include the following quantities:

1. Diameter of steady circulation – D c = 2R c.

The diameter of the steady circulation is the diameter of the trajectory of the central heating movement. the vessel at a steady circulation period.

For a comparative assessment of the turnability of various vessels, the value D c(or R c) are usually expressed in terms of the length of the ship's hull L. This ratio is called the main measure of the ship's turnability and this value is the relative diameter of the circulation ( D COT).

For inland navigation vessels D COT lies within 2.5 3.5.

2. Tactical circulation diameter D T- the distance between the center line of the vessel on a straight course and its position when turning 180 °.

D T = (6.5)

where L- length of the vessel, m;

T- draft of the vessel, m;

S P- steering wheel area, m 2;

To OP Is the experienced coefficient.

usually magnitude D T = (0,9 – 1,2)D c.

Rice. 6.3 Ship circulation diagram

3. Extension l 1–The distance by which the center of gravity of the vessel shifts in the direction of the original heading from the point of the beginning of the circulation to the point corresponding to the change in the vessel’s heading by 90 o. For various ships l 1 fluctuates within l 1 = (0,6 -1,5)D C.

4. Forward displacement l 2- the shortest distance from the line of the initial course of the vessel to the point at which the center of gravity (c.t.) coincides at the time of the course change by 90 o; usually l 2 = (0,25 -0,50)D c.

5. Reverse displacement l 3- the greatest distance by which the c.t. is displaced. ship to the side, reverse direction turning; usually l 3 = (0,01 – 0,1)D c.

The speed-time characteristics include:

1. Circulation period Т Ц- the time of the ship's turn by 360 o.

2. Linear speed of movement of Ts.T. ship on steady circulation - V c.

3... Angular speed of rotation of the vessel on steady circulation ω.

The drift angle of the vessel on the circulation is determined by the C.T. aft and bow respectively β C , β K and β C.

The assessment of the ship's reaction to the steering gear shift is determined by the recall coefficient k withdrawal, which is expressed by the ratio of time t o from the beginning of shifting the steering device of the vessel to the required amount of shifting, to the time of the beginning of the turning of the vessel.

K rev = (6.7)

For single vessels, this coefficient, as a rule, tends to one, and for pushed convoys it is much less, since pushed convoys after the end of the transfer of the control body continue to move on the same course for some time.

The width of the fairway required for movement is determined by the circulation parameters along the stern end of the ships and trains, since the stern end of the ship moves along a curve of a larger radius than its Ts.T.

In accordance with (Fig. 6.4), the trajectory elements of the aft end of the vessel in circulation, it is advisable to estimate the maximum reverse displacement of the aft end. Largest diameter, called the diameter of the circulation at the stern of the vessel, will characterize the circulation movement extreme point aft end of the ship. The diameter of the circulation at the stern of the vessel will be

D К = D Ц + L Р sinβ (6.8)

where L Р - distance from Ts.T. the vessel to the point of application of the forces P P (to the stern).

Knowing the value D K, the boatmaster can estimate the size of the water area required for the turnover.

Figure 6.4. Changing the drift angle along the length of the vessel and the radius of circulation.

Table 6.1. data on the relative radii of the established circulation of some inland navigation vessels are given.

Table 6.1.

6.2.3 Heel during circulation.

In the course of circulation, the vessel gets heeled (Figure 6.5). The magnitude and side of the roll angle depends on the period of circulation the vessel is in. In the maneuvering period of circulation, under the action of steering force (RU), the roll is directed towards the side, to which shifted steering wheel. During the evolutionary period, the ship first straightens, as a result of the action of the restoring moment of stability, and then acquires the maximum dynamic heel outward circulation, as the centripetal force begins to operate. After one or two oscillations, by the beginning of the period of steady circulation, the vessel acquires static roll directed outward circulation, which can be determined by the formula of G.A. Firsov

θ about max = 1.4 (6.9)

where θ about max – maximum value roll angle on steady circulation;

V o- speed of movement of the vessel on a straight course, m / s;

Z D- ordinate of the center of gravity of the vessel relative to the main plane, m;

h- initial metacentric height of the vessel, m;

T and L- draft and length of the vessel, m.

Methocentric height ( h) Is the distance between the metocenter and the center of gravity (Ts.T.) of the vessel

Methocenter ( M) Is the point of intersection of the resultant forces of water pressure with the DP.

The most dangerous roll occurs when the wheel is circulating at full speed with the rudder on board.

The dynamic heel in the evolutionary period of circulation in its magnitude can exceed the heel in the steady period by more than 2 times.

In vessels with low stability, the roll on the circulation at full speed can reach 12 - 15 o. On the passenger ships a roll on the circulation of more than 7 ° is not desirable, and more than 12 ° is considered unacceptable.

To reduce the roll angle of the vessel on the turnover, it is necessary to reduce the speed of movement before entering the turnover. The boatmaster can determine the limits of change in the speed of the vessel's movement before entering the circle from the Stability Information available on the vessel.

Figure 6.5 The list of the vessel during circulation.

Failure to take these factors into account can lead to tragic consequences and disasters. As an example, we can cite the disaster of the motor ship "Bulgaria", which occurred at the Kuibyshev reservoir.

The motor ship "Bulgaria", cruising on the route Kazan - Bolgar - Kazan, sank on July 10, 2011 in the Volga near the village of Syukeevo, Kamsko-Ustinsky region of Tatarstan.

According to the report of Rostransnadzor, “at about 12:25 pm on July 10, the vessel came under the influence of a strong gust of wind from the port side, a heavy downpour with a thunderstorm began. At this moment D / E "Bulgaria" entered the left turn. It should be noted that when the rudders are shifted to the left, all motor ships acquire an additional dynamic roll to the starboard side.

As a result, the roll angle was 9 degrees. “With such a heel, the portholes on the starboard side entered the water, as a result of which about 50 tons of seawater entered the ship's compartments through the open windows in 1 minute. In order to reduce the area of ​​effect of the wind on the port side, the captain decided to take a heading "to the wind". For this, the rudders were put 15 to the left. " As a result, the list increased and the total amount of water entering the vessel's compartment reached 125 tons per minute. After that, all the windows and part of the main deck of the starboard side were submerged in the water. Over the last 5-7 seconds, there was a sharp increase in the list from 15 to 20 degrees, as a result of which the vessel capsized on the starboard side and sank.

The Commission concluded that one of the causes of the accident was the fact that the left turn maneuver was carried out without taking into account the stability features of the vessel, which had already heeled 4 degrees to starboard; additional roll to starboard caused by centrifugal force during circulation to the left; a strong wind blowing to the port side and a large sail of the vessel.

Changing the speed of movement of the vessel on the circulation can be achieved by regulating the mode of operation of ship propellers by decreasing the speed of rotation of the propeller before the circulation and in its process, as well as by using the propellers in different directions - "frustrate" (which is possible with a multi-shaft installation on the ship).

Decreasing the speed of the vessel before the circulation causes a decrease in the extension of the circulation l 1 and its tactical diameter D T, which clearly illustrates (Fig. 6.6).

Figure 6.6. The circulation of the ship at different initial speeds.

After the ship has entered steady circulation, the rotation frequency of the propellers can be increased to increase the turning intensity, which does not significantly change the geometric characteristics of the circulation.

A significant reduction in the required water area for the production of circulation can be achieved by using a maneuver called "turnover". In this case, the ship is stopped before the start of the maneuver, the rudders are shifted to the maximum angle of the corresponding side and the propellers are given full speed to the front. The vessel immediately enters the circulation, the size of which is smaller than when moving at low speed, and the maneuver time decreases.

The diameter of the circulation is influenced by:

a) the area of ​​the rudder; the larger it is, the smaller the circulation diameter.

To increase the rudder area, several rudders are installed, active rudders and steering nozzles are used.

b) distribution of cargo on the ship; if the cargo is concentrated in the middle part of the vessel, then it turns faster, with a smaller circulation diameter, and if at the ends - slower, with a larger circulation diameter;

c) in relation to the length of the vessel to its breadth; the larger the ratio, the larger the circulation diameter;

d) the area of ​​the immersed part of the diametral plane; the larger it is, the larger the circulation diameter;

e) trim of the vessel; with a differential to the bow, the vessel has slightly better agility than with a differential to the stern.

As a conclusion, we can say that when sailing along the GDP, the vessel constantly moves along curved trajectories and makes a large number of circulations. Therefore, knowledge of the elements of circulation is of great importance for ensuring the safety of navigation of ships.

If the rudder blade is removed from the centreline plane (DP) of the vessel, the vessel will move along a curved trajectory. This trajectory, described by the center of gravity of the ship, is called circulation.

There are four periods of circulation: preliminary, maneuverable, evolutionary and steady circulation.

The preliminary period is the time from the moment the command is given to the helmsman until the beginning of the rudder blade shift.

The maneuverable period is the time from the moment the rudder starts shifting to the moment it ends.

The evolutionary period is the time from the moment of the end of the rudder shift until the moment when the elements of movement take on a steady character.

The period of steady circulation is from the moment the ship's center of gravity moves along a closed curve.

In the initial, evolutionary period of circulation, a hydrodynamic force acts on the rudder rudder removed from the DP, one of the components of which is directed perpendicular to the DP, and causes drift of the vessel. Under the action of the propeller stop and lateral force, the vessel moves forward and shifts to the side opposite to the rudder shift. Therefore, along with the drift, there is a reverse displacement of the vessel in the direction opposite to the turn. The circulation trajectory is distorted at the first moment. The reverse displacement decreases as the centrifugal force of inertia, applied to the center of gravity of the vessel and directed outward of the turn, increases. Reverse displacement moves the vessel out of the circulation. And although it does not exceed the half-width of the ship, it must be taken into account, especially when sharp turns in the narrowness.

During the period of steady circulation, the moments of forces acting on the rudder and the hull of the ship are balanced and the ship moves in a circle. Violation of the parameters of the ship's movement can occur when the rudder angle, the ship's speed, or under the influence of external forces change.

The main elements of a vessel's circulation are diameter and period. The circulation diameter characterizes the ship's turnability. Distinguish between the tactical diameter of the circulation Dt and the diameter of the steady circulation Dc (Fig. 163).

Tactical circulation diameter Dt - this distance between the initial course of the vessel and after its turn by 180 ° is 4-6 lengths of sea transport vessels.

The diameter of the steady circulation Dц - it is the diameter of the circle along which the ship's center of gravity moves during steady circulation.

The tactical circulation diameter is about 10% larger than the established circulation diameter.

The diameter of the circulation depends on many factors: length, width, draft, load, vessel speed, trim, roll, side and angle of laying, number of propellers and rudders, etc.

When circulating. DP of the vessel does not coincide with the tangent to the curved trajectory of the center of gravity. As a result of this, a drift angle P is formed. The bow of the vessel is displaced inward of the circulation curve, and the stern moves outward. With increasing speed, the drift angle increases, and vice versa. Due to the presence of the drift angle, the vessel on the circulation takes a strip of water more than its size. This must be taken into account by skippers when maneuvering and diverging in confined navigation conditions.

The next element characterizing the ship's turnability is circulation period. This is the time it takes for the ship to turn 360 °. It depends on the speed of the boat and the rudder angle. With an increase in speed and rudder angle, the circulation period decreases. When the rudder is shifted at the initial moment, a roll of the vessel appears in the direction of the turn. It disappears at the beginning of the turn on the turn, and with further movement the ship gets a roll in the opposite direction of the turn. This is due to the fact that the heeling moment acts on the vessel at first. M "cr, forceful R - water pressure on the rudder and force R lateral resistance (Fig. 164). With the further turn of the vessel, the centrifugal force of inertia begins to act on it TO, applied to the ship's center of gravity (G) and directed outward of the turn, and lateral drag force R. These two forces form a moment M "cr, much larger than the M "cr, which heels the ship on the opposite side of the rudder (opposite side of the turn). The above explanation is simplified. In reality, the distribution of forces during the turn is more complicated.

The action of forces on the circulation

Determination of circulation elements

Determination of circulation elements can be done in many ways: using radar, phase RNS, floating objects, on alignments, along two horizontal angles, by bearing and vertical angle, etc.

The circulation elements are determined empirically for the main modes of the main engine (full, medium, small, smallest), when turning through the port and starboard sides, in ballast and in full load.

By circulation call the trajectory described CT when moving with the rudder deflected at a constant angle. The circulation is characterized by linear and angular velocities, radius of curvature and drift angle. The angle between the vector of the linear speed of the vessel and DP are called drift angle... These characteristics do not remain constant throughout the entire maneuver.

It is customary to divide circulation into three periods: agile, evolutionary and steady-state.

First period (maneuverable)- the period during which the rudder is shifted to a certain angle. From the moment the rudder begins to shift, the vessel begins to drift in the direction opposite to the rudder shift, and at the same time, under the influence of forces Y p and Y p “ begins to turn towards the rudder shift. During this period, the trajectory of movement CT the vessel from rectilinear turns into curved with the center of curvature on the side of the side opposite to the side of the rudder; there is a drop in the speed of the vessel.

Second period (evolutionary)- the period starting from the moment of the end of the rudder shift and continuing until the moment when the equilibrium of all forces acting on the ship occurs, and the drift angle ( β ) ceases to grow and the speed of movement of the vessel along the trajectory also becomes constant. During this period, the hydrodynamic forces of pressure on the ship's hull increase, the drift angle increases, the curvature of the trajectory changes sign, and the center of the curvature of the trajectory moves inside the circulation. The speed of movement of the vessel along the trajectory, which began to decrease during the maneuvering period, continues to decrease. The radius of the trajectory in the evolutionary period is a variable value.

Third period (steady state)- the period starting after the end of the evolutionary one is characterized by the balance of forces acting on the ship: the propeller stop, hydrodynamic forces on the rudder and hull, centrifugal force. The trajectory of the ship's CG is converted into a trajectory of a regular circle or close to it.

Circulation elements

Geometrically, the circulation trajectory is characterized by the following elements:

Do – diameter of steady circulation- the distance between the diametrical planes of the vessel on two successive courses, differing by 180º at steady motion;

D c – tactical circulation diameter DP the vessel before the start of the turn and at the moment when the course is changed by 180º;

l 1 - advance (gait)- distance between positions CT before turning the vessel up to the turning point at which the vessel's heading changes by 90º;

l 2 - forward displacement- distance from the original position CT the vessel to its position after turning by 90º, measured along the normal to the initial direction of movement of the vessel;

l 3 - reverse bias- greatest displacement CT the vessel as a result of a drift in the direction reverse side rudder shifting (reverse offset usually does not exceed the boat's breadth V , and on some ships is absent at all);

T c - circulation period- time of the ship's turn by 360º.

The above characteristics of the circulation in sea transport vessels of medium tonnage with full rudder shifting on board can be expressed in fractions of the ship's length and through the diameter of the established circulation by the following ratios:

Dо = (3 ÷ 6) L ; Dts = (0.9 ÷ 1.2) D y; l 1 = (0.6 ÷ 1.2) Dо;

l 2 = (0.5 ÷ 0.6) D about ; l 3 = (0.05 ÷ 0.1) D о; T c = πD o / V c.

Usually the values D about; D c; l 1; l 2; l 3 expressed in relative form (divided by the length of the ship L ) - it is easier to compare the agility of different vessels. The smaller the dimensionless ratio, the better the agility.

Turning speed for large vessels is reduced when turning 90º with rudder on board ≈ on the ⅓ , and when turning 180º - twice.

For an arbitrary point along the length of the vessel " a The drift angle is determined from the well-known trigonometry formulas:

where l a - distance of the point " a "From CT(into the nose - " + "; in the stern - " – »).

The following provisions should be noted:

a) the initial speed has an effect not so much on D about how much for her time and nominated; and only high-speed vessels show some changes D about upward;

b) when the vessel enters the trajectory of circulation, it acquires a heel on the outer side, the value of which, according to the rules of the Register, should not exceed 12º;

c) if during circulation to increase the number of revolutions DG, the ship will make a steeper turn;

d) when performing circulation in confined conditions, it should be borne in mind that the stern and bow ends of the vessel describe a strip of considerable width, which becomes commensurate with the width of the fairway.

Safe turning is ensured provided that the width of the traffic lane in meters:

where R c.w. - the average radius of curvature of the circulation in the section from the initial to the course changed by 90º;

β k - the angle of the vessel's course change;

β

The roll angle at steady circulation can be determined by the formula of G.A. Firsov:

where V 0 - ship speed on a straight course (in m / s);

h - initial transverse metacentric height (m);

L - length of the vessel (m);

z g - ordinate CT vessel;

d - average draft of the vessel.

The agility of the vessel is the ability to change the direction of movement under the influence of the rudder (controls) and move along the trajectory of a given curvature. The movement of a vessel with a shifted rudder along a curved trajectory is called circulation.
The vessel's circulation is divided into three periods:
- maneuverable, equal to the rudder shift time;
- evolutionary - from the end of the rudder shift until the moment when the linear and angular velocity of the vessel acquire steady-state values;
- steady-state - from the end of the evolutionary period and until the steering wheel remains in the shifted position.
It is impossible to define a clear boundary between the evolutionary period and the established circulation, since the change in the elements of motion fades out gradually. It can be conventionally considered that after a turn by 160-180 °, the movement acquires a character close to the steady-state one. Thus, the practical maneuvering of the vessel always occurs in an unsteady mode.
The trajectory of the curvilinear movement of the ship's center of gravity, that is, its circulation is characterized by the following elements (Fig. 1):

1. The diameter of the circulation is the main characteristic of the ship's (vessel's) turnability. Distinguish between the diameter of the tactical circulation and the diameter of the established circulation. The value of the circulation diameter depends on the ratio of length to width, rudder area and rudder angle, as well as the speed of the ship and the absence of the influence of external forces such as wind, waves and current. The circulation diameter is measured in meters, cable lengths or ship hull lengths (on average, it ranges from 4 to 8 hull lengths).
Tactical circulation diameter (Dt) is the normal distance between the return heading lines after turning the ship through the first 180 °. Determined at 15 ° and 25 ° rudder angles.
The diameter of the steady circulation (Dust) is the diameter of the circle along which the ship's center of mass moves after the angular velocity and roll on the circulation become constant, usually after the ship turns 180 °.
2. Extension (l1) - the distance by which the center of gravity of the vessel is shifted in the direction of the original heading from the point of the beginning of the circulation to the point corresponding to the change in the vessel’s heading by 90 °.
3. Forward displacement (l2) - the distance from the initial course of the vessel to the point of the center of gravity at the moment the vessel turns 90 °;
4. Reverse displacement (l3) - the greatest distance by which the center of gravity of the vessel is displaced from the line of the initial heading in the direction opposite to the turn.
The values ​​of the circulation elements, expressed in fractions of the circulation diameter Dust, lie within relatively narrow limits and for vessels of various types change as follows:
Dt = (0.9 ± 1.2) × Dust;
l1 = (0.6 ± 1.3) × Dust;
l2 = (0.25 ± 0.5) × Dust;
l3 = (0 ± 0.1) × Dset.
For sea transport vessels, Dust is 4-6 vessel lengths. In addition to these elements, circulation characteristics include:
- period of steady circulation:
T is the time of the ship's turn by 360 °;
- the angular velocity of rotation of the vessel at steady circulation:
ω = 2π / T.
With an error of 5%, we can assume that the speed of transport vessels in circulation with a rudder on board when turning 60 ° is 80%, 90 ° - 73%, 180 ° - 58% of the original.
It is more convenient to express the elements of circulation during maneuvering in dimensionless form - in hull lengths: in this form it is easier to compare the turnability of different vessels. The smaller the dimensionless value, the better the agility. Circulation elements of a conventional transport vessel for a given rudder angle are practically independent of the initial speed at steady state engine operation. If, when shifting the rudder, the propeller speed is increased, the vessel will make a turn more abruptly than with the unchanged mode of the main engine.
When performing the circulation, you can determine its elements if you make successive determinations of the ship's position by some landmarks at short time intervals (15-30 s.). At the time of each observation, the measured navigation parameters and the ship's heading are recorded. By putting the points on the tablet and connecting them with a smooth curve, the trajectory of the vessel is obtained, from which the circulation elements are removed on the accepted scale. The position of the vessel can be determined from the bearing and distances of a free-floating landmark such as a raft. With this method, the influence of an unknown current is automatically excluded, and a special polygon is not required.

By circulation call the trajectory describedCT when moving with the rudder deflected at a constant angle. The circulation is characterized by linear and angular velocities, radius of curvature and drift angle. The angle between the vector of the linear speed of the vessel andDP are calleddrift angle ... These characteristics do not remain constant throughout the entire maneuver.

It is customary to divide circulation into three periods: agile, evolutionary and steady-state.

First period (maneuverable) - the period during which the rudder is shifted to a certain angle. From the moment the rudder begins to shift, the vessel begins to drift in the direction opposite to the rudder shift, and at the same time, under the influence of forces Y p andY p " begins to turn towards the rudder shift. During this period, the trajectory of movementCT the vessel from rectilinear turns into curved with the center of curvature on the side of the side opposite to the side of the rudder; there is a drop in the speed of the vessel.

Second period (evolutionary) - the period starting from the moment of the end of the rudder shift and continuing until the moment when the equilibrium of all forces acting on the vessel occurs, and the drift angle(β ) ceases to grow and the speed of movement of the vessel along the trajectory also becomes constant. During this period, the hydrodynamic forces of pressure on the ship's hull increase, the drift angle increases, the curvature of the trajectory changes sign, and the center of the curvature of the trajectory moves inside the circulation. The speed of movement of the vessel along the trajectory, which began to decrease during the maneuvering period, continues to decrease. The radius of the trajectory in the evolutionary period is a variable value.

Third period (steady state) - the period beginning at the end of the evolutionary one is characterized by the balance of forces acting on the ship: the propeller stop, hydrodynamic forces on the rudder and hull, centrifugal force. The trajectory of the ship's CG is converted into a trajectory of a regular circle or close to it.

Circulation elements

Geometrically, the circulation trajectory is characterized by the following elements:

Do - diameter of steady circulation - the distance between the diametrical planes of the vessel on two successive courses, differing by 180º at steady motion;

D c - tactical circulation diameter - distance between positionsDP the vessel before the start of the turn and at the moment when the course is changed by 180º;

l 1 - advance (gait) - ra
distance between positionsCT before turning the vessel up to the turning point at which the vessel's heading changes by 90º;

l 2 - forward displacement - distance from the original positionCT the vessel to its position after turning by 90º, measured along the normal to the initial direction of movement of the vessel;

l 3 - reverse bias - greatest displacementCT due to drift in the direction opposite to the rudder position (the reverse displacement usually does not exceed the ship's breadthV , and on some ships is absent at all);

T c - circulation period - time of the ship's turn by 360º.

The above characteristics of the circulation in sea transport vessels of medium tonnage with full rudder shifting on board can be expressed in fractions of the ship's length and through the diameter of the established circulation by the following ratios:

Dо = (3 ÷ 6) L ; Dц = (0.9 ÷ 1.2) D at ; l 1 = (0.6 ÷ 1.2) Dо ;

l 2 = (0.5 ÷ 0.6) D O ; l 3 = (0.05 ÷ 0.1) D O ; T c = πD O / V c .

Usually the values D O ; D c ; l 1 ; l 2 ; l 3 expressed in relative form (divided by the length of the shipL ) - it is easier to compare the agility of different vessels. The smaller the dimensionless ratio, the better the agility.

Turning speed for large vessels is reduced when turning 90º with rudder on board≈ on the⅓ , and when turning 180º - twice.

For arbitrary length su
bottom of the point "a The drift angle is determined from the well-known trigonometry formulas:

,

wherel a - distance of the point "a "FromCT (into the nose - "+ "; in the stern - "- »).

The following provisions should be noted:

a) the initial speed has an effect not so much onD O how much for her time and nominated; and only high-speed vessels show some changesD O upward;

b) when the vessel enters the trajectory of circulation, it acquires a heel on the outer side, the value of which, according to the rules of the Register, should not exceed 12º;

c) if during circulation to increase the number of revolutionsDG , the ship will make a steeper turn;

d) when performing circulation in confined conditions, it should be borne in mind that the stern and bow ends of the vessel describe a strip of considerable width, which becomes commensurate with the width of the fairway.

Safe turning is ensured provided that the width of the traffic lane in meters:

whereR c.w. - the average radius of curvature of the circulation in the section from the initial to the course changed by 90º;

β k - the angle of the vessel's course change;

β is the drift angle.

The roll angle at steady circulation can be determined by the formula of G.A. Firsov:

(in degrees),

where V 0 - ship speed on a straight course (in m / s);

h - initial transverse metacentric height (m);

L - length of the vessel (m);

z g - ordinate CT vessel;

d - average draft of the vessel.

TABLE OF MANEUVERABLE ELEMENTS

The maneuverable elements of the vessel are initially determined whenwater and full-scale tests for two displacement - a vessel #000000">with a full load and empty. Based on tests performedand additional calculations make up information about the maneuverable elements of the vessel(IMO Resolution No. A.601 (15)"Requirements for the display of maneuverable information on ships") ... The information consists of two parts:table of maneuverable elements, posted on the chassistic; additional information, taking into account the specifics of thisof the vessel and the dynamics of the influence of various factors on the maneuverablethe quality of the vessel under various sailing conditions.

To determine the maneuverable elements,any full-scale and full-scale calculation methods that provide accuratefinal results within ± 10% of the measured valueus. Full-scale tests are carried out in favorable weather conditions: wind up to 4 points, waves up to 3 points, sufficient depthbinet and without a noticeable current.

The table of maneuverable elements includes inertialcharacteristics of the vessel, elements of turnability, change in draftship, elements of propulsion, elements of maneuver for rescuing peopleka who fell overboard

Inertial characteristics are presented as lineargraphs built on a constant scale of distances and havethe scale of time and speed values. Braking distance from fronttheir moves to "Stop" are limited by the moment of loss of controllableship or final speed equal to 20% of the original. On the graphkax show with an arrow the most probable side of deviationfrom the initial track in the process of decreasing the speed.

Information about the agility is given in the form of a graph andblitz. The circulation graph reflects the position of the vessel after 30 °to the trajectory to the right and to the left with the rudder position "on board" and "onhalf board ". Similar information is presented in tabular form, but every 10 ° change in the initial course in the rangenot 0-90 °, for every 30 ° - in the range of 90-180 °, for every 90 ° - inrange 180-360 °. At the bottom of the table, data aboutthe largest diameter of the circulation.

Movement elements are reflected in the form of a graphical dependencespeed of the vessel from the speed of the propeller and complementthe table, where the hour is indicated for each constant speed value.the rotation of the propeller.

The increase in the ship's draft is taken into account when heeling and sagging, when the ship moves at a limited depth with a certaingrowth.

Elements of a maneuver to rescue a person who has fallen overboard,
font> performed by receiving coordinates to the starboard or port side. In the informationMats indicate the following data for performing the correct maneuver: angle of turn from the initial course; operational timeshifting the rudder to the opposite side, entering the countercourse andto the starting point of the maneuver; actions of the boatmaster at every stageevolution.

V

all distances in the information on the maneuverable elements of the drivefire in cables, time in minutes, speed in knots.

Additional information may include materially, taking into account the specific features of specific typesvessels, information about the influence of various factors on the maneuvering data of the vessel, etc.

The table of maneuverable elements is an operational minimum of data that is mandatory for each ship, which can be supplemented at the discretion of the ship's master or the maritime service.

The table should include:

Inertial characteristics.

(PPH - stop; PMPH - stop; SPH - stop; MPH - stop; PPH - PZH; PMPH - PZH; SPH - PZH; MPH - PZH; acceleration from the "stop" position to full forward travel).

The inertial characteristics are presented in the form of graphs built on a constant scale of distances and having a scale of values ​​of time and speed.

Braking distances from forward to “stop” should be limited to the moment of loss of control of the vessel or the final speed equal to 20% of the full speed, whichever is the greater.

Possible direction (arrow) and value (in kbt) of the vessel's lateral deviation from the initial track line and course change at the end of the maneuver (in deg.) Are indicated above the inertial and stopping distance graphs. The listed characteristics are presented for two displacement of the vessel - in cargo and in ballast.

Agility elements.

In the form of a graph and a table with the circulation of the PPH to the right and left sides in cargo and in ballast with the rudder position "on board" (35 degrees) and "half-board" (15 - 20 degrees).

The information should contain time intervals for every 10 degrees, in the range of changes in the initial course of 0 - 90 degrees (on the graph, it is enough after 30 degrees), for every 30 degrees in the range of 90 - 180 degrees, for every 90 degrees in the range of 180 - 360 degrees; largest circulation diameter; the extension of the vessel along the line of the initial heading and displacement along the normal to it; initial, intermediate (90 degrees) and final speeds; the drift angle of the vessel in circulation.

Elements of travel. (Loaded and Ballast).

Dependence of the ship's speed on the propeller speed (CPP position) in the form of a graph and a table at a constant interval in revolutions. The zone of critical revolutions is highlighted on the graphs with a conventional sign (color).

Change in ship draft under the influence of heel and subsidence.

Left: 0.75cm; margin-bottom: 0cm "class =" western "align =" justify "> Elements of maneuver to rescue a person who has fallen overboard. (For starboard and port side); the angle of rotation from the initial course; the operational time of shifting the rudder to the opposite side; entering the counter course and arriving at the starting point of the maneuver; appropriate action(dropping a circle, giving a command to the helmsman, announcing an alarm, observing the fallen and the circle).

2 MISSING OF THE SHIP ABROAD

SHIP'S DEPARTURE TO CABOTAGE

COMING FROM ABROAD

COMING FROM CABOTAGE

Ship documents

Issued by the Harbor Master

Certificate of the right to sail under the State flag of Russia

Certificate of ownership of the ship (unlimited)

Minimum Crew Certificate

Certificate of Provision of Civil Liability for Damage from Oil Pollution

Ship documents issued by the technical supervision body:

Passenger certificate

Permit for the right to use a ship radio station

Cargo Ship Safety Radiotelegraphy Certificate

Load line certificate (lowest freeboard)

Regional cargo certificate

Ship documents required by international conventions.

Passenger Ship Safety Certificate

Cargo Ship Safety Certificate of Construction

Cargo Ship Safety Certificate for Equipment and Supplies

Safety Certificate of a cargo ship by radiotelegraphy

Cargo Ship Safety Certificate by Radiotelephony

Withdrawal certificate

Nuclear Passenger Ship Safety Certificate(nuclear passenger ship) andNuclear Cargo Ship Safety Certificate [email protected] site