The tiller compartment should be sufficiently illuminated day and night, in the parking lot it should be closed, in cold weather it should be heated. It is not allowed that there are foreign things in it.
You need to follow:
· In winter - over the temperature of the tiller room;
· When the vessel is parked in ice - so that the rudder has the ability to turn freely;
· When reversing in ice - ensure that the steering wheel is installed in the center plane.
It is necessary to store serviceable tiller-hoists with a set of fastening parts near the rudder sector (tiller).
After the end of mooring, the rudder must be placed in the center plane.
The following defects in the steering gear are not allowed:
a) stressed parts (including chains and rods of the steering rope) with an average wear of 1/10 or more of the construction thickness or diameter, as well as cracks or permanent deformations, should not be allowed for operation;
b) the steel cable in the steering drive system must be replaced if, anywhere along its length equal to 8 diameters, the number of wire breaks is 1/10 or more of the total number of wires, as well as in case of excessive deformation of the cable;
c) when twisting at an angle of 15 ° or more and if cracks are found, the stock must be replaced.
When the vessel is parked for a long time or when it is being repaired, all undercarriages of the steering gear must be carefully preserved.
Steering Commands.
The master of the ship assigns the course and speed of the ship through the officer in charge of the watch. In some cases (when determining the maneuverable elements, adjustments of instruments or sailing in narrowness), by the decision of the captain, the right of direct command to the rudder may be given to the navigator.
In order to successfully complete turns using the rudder, the ship's master and officer in charge of the navigational watch must know the following information:
Diameter of circulation when shifting the rudder to different angles to the right and to the left in different operating modes main machines;
· The time of the description of the complete circulation and its part at various speeds and combinations of operating machines;
· Loss of speed on circulation when shifting the rudder to a set number of degrees for different speeds;
· "Dead time" from the moment the command is given to the helmsman until the start of the actual turn;
· The possible value of the roll angle of the ship on the circulation, depending on the speed of the course.
When performing a turn, they are guided by the following rules:
· Before giving a command to the steering wheel, it is necessary to assess the situation and take all measures to safely perform the maneuver;
· You should resort to shifting the rudder “on board” only if absolutely necessary (when the vessel is turning in a narrow space, to avoid collision with another vessel, to avoid the detected navigational hazard);
· It is necessary to ensure the possibility of a quick transition to spare steering positions;
· When sailing together, the turn of the vessel must be indicated by an established sound and light signal in accordance with the MPPSS-72 at the moment the command is given to the rudder;
Commands to the steering wheel must be given in strict accordance with the "Command words" The given commands must be rehearsed by the helmsman in a loud voice, preceding them with a word "There is".
The following basic steering wheel commands are accepted:
1. Team "Right (left) aboard" means that the steering wheel should be put to the set limit in the indicated direction. The command is given taking into account the rapid shift of the rudder.
By command "Right (left) rudder" the helmsman is obliged to shift the rudder to the specified number of degrees (for a given vessel) in the indicated direction and report: "Steering wheel right (left) so and so." ( Usually 15 0 ) During the turn, the helmsman reports new heading values every 10 °. This command is issued when making normal turns to a new course. When performing a turn with a larger or smaller than usual diameter of the circulation, the command “ So many degrees of the right (left) rudder ”.
Command" Divert»Is given when the vessel approaches the designated course (usually 10-15 °). At this command, the rudder is retracted to the ship's DP, after which the helmsman reports: “ Steering wheel straight". Similar actions are performed by the command “ Steering wheel straight". The command is issued if necessary to interrupt the execution of the turn. After the commands "Retract" and "Straight rudder" the helmsman reports the course every 3 °.
Command" Obsess b "is given when 3-5 ° is left before the appointed new course. At this command, the steering wheel is shifted a small number of degrees to the side opposite to the circulation. The helmsman reports the compass heading every degree.
Command " Keep it up"Means that the helmsman must notice from the compass with an accuracy of a degree the course on which the ship was lying at the moment of giving the command, or the direction along the coastal landmark and keep the ship on this course, reporting:" Yes, keep it up, there are so many degrees on the rumba».
Request command " On the rumba?"Means that the helmsman should notice the compass heading and report:" There are so many degrees on the rumba».
Command " So many degrees to the right (left) according to the compass " means that the helmsman must change the course by a certain number of degrees, and then report: “ There are so many degrees on the rumba". The command is given in cases when it is necessary to change the course of the vessel by no more than 15-25 °.
An experienced helmsman can be given the following commands: « Right (left) rudder. The course is so many degrees "; " Keep in the wake of such and such a vessel»; « Lie on target»; « Leave such and such an object to the right (left)" etc.
In this case, the helmsman independently performs the specified actions and reports: “ On site. There are so many degrees on the rumba" or " There are so many degrees on the rumba" etc.
| Steering wheel straight | Midships | Bring the steering wheel to the center plane |
| Steering wheel left / right 5 degrees | Port / starboard five | Put the steering wheel 5 degrees to the left / right |
| Steering wheel left / right 10 degrees | Port / starboard ten | Put the steering wheel 10 degrees left / right |
| Steering wheel left / right 15 degrees | Port / starboard fifteen | Put the steering wheel 15 degrees left / right |
| Steering wheel left / right 20 degrees | Port / starboard twenty | Put the steering wheel 20 degrees left / right |
| Steering wheel left / right 25 degrees | Port / starboard twenty-five | Put the steering wheel 25 degrees left / right |
| Steering wheel left / right side! | Hard a port / starboard | Put the steering wheel left / right on the side to the limit |
| Steering half board left / right! | Half a port / starboard | Put the steering wheel to the left / right at about 15 degrees |
| Left / right don't walk! | Northing to port / starboard | Maintain the ship on a given course so that when yawing, the ship's course does not go to the left / right of the given course |
| Obsess! | Steady! Meet the helm! Meet her! | Reduce the steering angle to a minimum and even, if necessary, shift to the other side. This is done to reduce the angular rate of turn of the vessel, so that at the moment of entering the new course line, it can stop on this line. |
| Keep it up! | Steady as she goes! Straight so! | This command is given the moment the vessel enters the new course line. The helmsman notices the course with an accuracy of 1 ° on the compass card, then, shifting the rudder so as to stop the vessel's further turn, leads him to this course |
| Little by little left / right! | Easy to port / starboard! Port / starboard handsomely! | Shift the steering wheel to the left / right by about 5-10 degrees |
| Keep in alignment! | Keep alignment in sight! | Keep the ship's course on the leading line |
| Follow the boat! | Follow the launch! | Maintain a wake behind the boat |
| Follow the tug! | Follow the tug! | Maintain the ship's course in wake after tug |
| Edit to the lighthouse! | Steer to the lighthouse! | The helmsman detects the course to the lighthouse and keeps to the lighthouse visually, controlling the course with the compass |
| Take it to 5 degrees! | Ease to five! | Take the steering wheel to the 5 ° position |
| Hold buoy / landmark / sign ... left / right! | Keep the buoy / mark / beacon ... on port / starboard side | Hold the ship's heading so that the buoy is left on port / starboard |
| Go to course 1 | Steer the course! | Move the rudder to the left / right side, through which you can quickly go to the specified course. Make sure that the ship does not accelerate during the turn, and at the time of entering a new course, detain the ship. |
| Right steering wheel! Stay on course ... (125) | Starboard! One, two, five | The rudder is shifted to the starboard side at an angle that depends on the magnitude of the course change. When entering the set course - the ship is delayed (125 °) |
| Left hand drive! Lie down at 305 °! | Port, steer three zero five (305) | See previous |
| Careful on the steering wheel! | Ming the helm! | The helmsman must be more careful when executing commands |
| How does the ship obey the helm? | What (how) does she answer the helm? | Report how the ship responds to rudder shifting |
| Report if the ship is not steering! | Report if she does not answer the wheel! | If the vessel stops responding to the rudder shift - report loudly |
| Move away from the steering wheel, you no longer need to control the steering wheel! | Finished with wheel, no more steering! | With the permission of the officer in charge of the watch, you can move away from the helm |
Watch at the gangway
While the vessel is at the berth, the sailor on duty must be at the gangway at all times. Duties of a sailor on watch:
Must be dressed in accordance with the established uniform and have an armband or badge;
Must ensure that there is a lifebuoy with a line at the top of the ladder and a rescue net fixed under the ladder. If the ladder cannot be put on the berth, then the gangway is fed from the lower platform, and it is necessary to check the reliability of its fastening. At subzero temperatures and the presence of precipitation, the ladder must be freed from snow and ice and, if necessary, sprinkled with sand; It is strictly forbidden to leave his post and be distracted by the performance of any work or assignments without the permission of the watch officer. In the event of an urgent need to leave the gangway, the sailor of the watch must call the officer of the watch and ask him for permission. The assistant is called by two calls or by radio. During the absence of the watch sailor, either the assistant himself remains at the post at the gangway, or he entrusts this post to another sailor;
Must know about the personnel of the daily watch for all basic services. In addition, it is important to always be aware of which of the officers is absent and who is currently on board. To do this, a "Watchboard" is installed at the gangway. The sailor on duty is obliged to note the presence of officers on board the ship;
During the entire watch, the sailor observes the environment on the ship and around the ship, in the area of the post. All cases that may affect the safety of the ship and people or adversely affect the general course of its production activities, the sailor of the watch shall immediately report to the officer in charge of the watch and then act on his instructions;
When taking out things or any items from the ship, the watchman at the gangway checks the duly issued pass from their owner. In the absence of such, detains the person and calls the watch officer;
When the captain leaves the board and returns to the ship, three calls are made. At this signal, the officer in charge of the watch immediately goes to the ladder;
The sailor on duty at the gangway has no right to let unauthorized persons on board without the permission of the assistant. Having stopped a man on board at the gangway, the sailor on duty calls an assistant, who checks the documents of the arriving person and asks him about the purpose of visiting the ship.
The identity document of the newcomer is kept by the helper or the sailor of the watch and returned to the owner upon leaving the ship. The officer in charge of the watch is obliged to accompany the arriving person from the gangway to the cabin where the visitor is heading. The return escort to the ladder is carried out by the one who received the visitor, or the assistant. If an unauthorized person was not accompanied when leaving the ship, the sailor on duty is obliged to report this to the mate;
The change of the sailors of the watch at the gangway is made only in the presence of the watch officer. An advancing sailor must be familiar with all watch orders concerning him.
In the event of a fire on the ship or near it, as well as in other emergency or other emergencies, the sailor on duty immediately announces the alarm on the ship, using loud chimes, the ship's bell and other means. He is obliged to know the methods of calling the coastal fire brigades and the location of the water columns closest to the vessel on the coast.
In case of alarms, the sailor of the watch at the gangway remains at his post, not allowing unauthorized persons to board the ship. He may leave his post only at the direction of the captain, chief officer or officer of the watch.
Commands to the helmsman
Right steering wheel!
1 Starboard!
2 Helm a-starboard!
3 Starboard the helm!
4 Port!
Left hand drive!
5 Helm a-port!
6 Port the helm!
7 Hard a-starboard!
Right aboard!
8 All starboard!
9 Hard a-port!
Left aboard!
10 All port!
11 Midships!
Steering wheel straight!
12 Amidships!
13 Right the helm!
14 Meet her!
Obsess!
15 Meet the helm!
16 Check the helm!
17 Hard over the helm! Obsess more!
18 Steady!
Keep it up!
19 Steady so!
20 Keep her steady!
21 Steady as she goes!
22 Straight so!
23 Right so!
More right!
24 Better (More) starboard!
More left!
25 Better (More) port!
Little by little right!
26 Starboard easy!
27 Easy to starboard!
28 Starboard a bit!
29 Port easy!
Little by little to the left!
30 Easy to port!
31 Port a bit!
On the course!
32 Steer the course!
The right not to walk!
33 Nothing to starboard!
Do not walk to the left!
34 Nothing to port!
Right rudder on course 030º!
35 Starboard on course 030º!
Left rudder on course 030º!
36 Port on course 030º!
Don't yawn on the steering wheel!
37 Mind the helm!
38 Watch your steering!
Follow the tug into the wake!
39 Follow the tug!
Follow the boat to the wake!
40 Follow the launch!
Follow the icebreaker to the wake!
41 Follow the icebreaker!
Commands for anchoring
1 Get the starboard anchor ready! Prepare the right anchor for recoil!
2 Get the port anchor ready! Prepare the left anchor for recoil!
3 Get both anchors ready! Prepare both anchors for recoil!
4 Stand by the starboard anchor! Stand at the right anchor!
5 Stand by the port anchor! Stay at the left anchor!
6 Let go the starboard anchor! Give up the right anchor!
7 Let go the port anchor! Give up the left anchor!
8 Pay away the cable (chain)! Etching the anchor - chain!
9 Keep the cable (chain) slackened! Hold the chain anchor weakly!
10 Hold on the cable! Stop the chain anchor!
11 Put the windlass in gear! Connect the windlass!
12 Be ready to heave in! Get ready to choose!
13 Heave in the starboard anchor chain! Choose the right chain anchor!
14 Heave in the port anchor chain! Choose the left chain anchor!
15 Heave in upon the cable! Choose an anchor - chain!
16 Avast heaving in the cable! Stop choosing an anchor - chain!
17 Disengage the windlass! Disconnect windlass!
18 Secure the anchor for sea!
Travel anchor!
19 The anchor is up and down! Apeak!
20 The anchor is apeak!
21 The anchor is atrip! The anchor is up!
22 How is anchor? How is the anchor?
23 Clear anchor! The anchor is clean!
24 Foul anchor! The anchor is not clean!
25 Stand clear of the anchor cable! Do not stand in front of the anchor ¬- chain!
26 Pay away three shackles of chain! Set three bows anchor - chains!
27 Heave short the cable! Pick up an anchor - a chain!
28 How is the cable leading? How does the anchor stand - the chain?
29 The cable is leading forward, starboard. Anchor - the chain is positioned forward on the starboard side.
30 The cable is leading aft, port. Anchor - the chain is positioned backwards on the port side.
31 Stand by fore and aft! All up!
32 All hands on deck!
Commands for mooring
1 Give on shore the heaving line! Submit tossing!
2 Send on shore the head rope! Submit bow!
3 Send on shore the stern rope! Submit stern!
4 Send on shore the bow spring! Submit nasal spring
5 Send on shore the stern spring! Feed the stern spring!
6 Send on shore the breast line! Submit the presser!
7 Pay away the bow spring! Put the nasal spring down!
8 Pay away the stern rope! Pose the stern!
9 Check the head rope! Hold up the nasal!
10 Check the stern spring! Stop the stern spring!
11 Check the breast line! Hold the clamp!
12 Make fast the bow spring! Attach the nasal spring!
13 Make fast the stern rope! Fix the stern!
14 Make all fast!
So fix it! (So we will stand!)
15 Cast off the head rope! Give back the bow!
16 Let go the head rope!
17 Heave in the bow spring! Vira nasal spring!
18 Hold on! Stop choosing!
19 Avast heaving in!
20 Veer out handsomely! Poison little by little!
21 Veer out cheerily! Poisoning is more fun!
22 Heave in aft! Choose aft mooring lines!
24 Haul in the slack! Pick up the slack!
25 Haul taut! Choose a tidy one!
26 Haul fast!
27 Ship the fenders! Fit fenders!
28 Unship the fenders! Remove fenders!
29 Fleet the cable upon the windlass! Bring (enclose) mooring lines on the windlass!
30 Lower down the ladder! Lower the ladder!
Commands for towing
1 Is the towing hawser fast? Is the tug secured?
2 The towing hawser is fast. The tug is fixed.
3 All fast. Everything is fixed.
4 Are you ready for towing? Are you ready for towing?
5 Everything is ready for towing. Everything is ready for towing.
6 Commence towing! Start towing!
7 I am commencing to tow. I start towing.
8 Shorten in the towing hawser! Shorten the tug!
9 I am altering my course to starboard. I turn right.
10 Steer to starboard! Go right!
11 Pay out the towing hawser! Pull the tug off!
12 Veer out the tow-line!
13 I must cast off the towing hawser. I have to hand over the tug.
14 Cast off the towing hawser! Give back the tug!
15 The towing hawser has parted. The tug burst.
16 Shall I continue the present course? Should I keep going the same course?
17 Continue the present course! Keep on following the same course!
18 Stop your engines at once! Stop your cars immediately!
19 I am stopping my engines. I stop my cars.
20 Keep away before the sea! Take away from the wave!
21 I am keeping away before the sea. I take away from the wave.
22 I must get shelter or anchor as soon as possible. I need to take cover or anchor as soon as possible.
24 Bring me to shelter or to an anchor as soon as possible. Lead me to a confined place or anchor me as soon as possible.
25 Shall we anchor at once? Should we anchor immediately?
26 I want to anchor at once. I want to anchor immediately.
27 Go slower! Reduce your stroke!
28 I will go slower. I will decrease the stroke.
29 My engines are going astern. My cars are running in reverse.
30 Go astern! Back up!
31 Increase your speed! Increase your stroke!
32 I am increasing my speed. I increase my stroke.
33 You are standing into danger. You are heading for danger.
34 I am paying out the towing hawser. I hunt the tug.
35 Get spare towing hawser ready! Prepare a spare tug!
36 Spare towing hawser is ready. The spare tug is ready.
37 I cannot carry out your order. I cannot fulfill your order.
28/04/2016
Going on a voyage as a sailor or deck cadet, sooner or later you will have to carry steering watch... This requires certain knowledge and skills. If sailor, at least, studied the material on this topic in the courses, then cadet can easily face this for the first time. Let's try to give a small introduction for a young sailor, we will analyze basic commands, let's study the principles manual control of the vessel.
So, we have a scheme for keeping a navigational watch on a navigational bridge of a civil merchant ship:
The Officer of the Watch or the Master himself shall ensure the safety of the navigational environment in which his ship is involved. Also, a sailor on duty is on duty on the bridge. turned on, fulfills and holds the ship on a given course. The sailor on duty performs the functions of the forward looking, reports to the navigator or the Captain about changes in the navigation picture, helps in determining bearings and heading angles. There are many reasons for switching to manual ship control such as passing narrows, dangerous banks, fairways, failure of the autopilot, deviations from the vessel at dangerous angles, a large angle of change of course and much more. So, the sailor receives the command from the watchman:
The person at the helm must be familiar with the system switching control mode... It is recommended to keep the steering wheel straight when shifting to avoid water hammer. After entering manual control of the vessel, the sailor makes a small shift of the rudder, checking system operability and the response of the rudder to the helm commands. If the navigator did not immediately set the course to be held, then the helmsman should report the current course read on gyrocompass repeater and then the course.
From now on 
You are the one who provides the manual and you have to understand everything you do. Principle of physical impact rudder feather to change the course of the vessel is concluded in system propulsiveness, namely with the speed of the vessel relative to the water and the work of the propeller... The rudder itself, from the point of view of physics, is a wing, when changing the angle of attack of which, a distribution of force occurs, creating ship's angular velocity as a physical body. And here it is worth taking into account that at certain speeds, appropriate steering angles are required. For example, our ship is at full speed, the speed over the water is 15 knots. At such a speed, shifting, say, 20 degrees to one side or the other, will create a sharp increase in the angular speed, roll of the vessel and generally not a comfortable situation on board. Such angles should be used in an emergency that requires an urgent solution.
Axiometer - a device that determines the position of the rudder blade relative to the center plane of the vessel.
Conversely, at a low speed, the moments of interaction between the rudder and the water are relatively small, and the helmsman has to move the steering wheel at large angles in order to get a response from the vessel, which stubbornly does not want to work out the angular speed.
So, we are given a course. Steering wheel straight... Unfortunately, the ship is subject to many external forces and constantly tries to independently deviate from the given trajectory. For this, the helmsman has to obsess when there is a tendency to change the course, as if to anticipate the situation, barely noticing the application to the angular velocity of the vessel.
If the vessel does not obey the helm, the helmsman must report it!
There is a well-established list of commands that a person on the steering wheel must clearly understand, know and execute.
| Right! | Starboard! |
| Left! | Port! |
| Right steering wheel! | Starboard the helm! |
| Left hand drive! | Port the helm! |
| More right! | More starboard! |
| More left! | More port! |
| Right aboard! | Hard - a - starboard! All starboard! |
| Left aboard! | Hard - a - port! All port! |
| Easier, take it away! | Ease the helm! |
| Easier right! | Ease to starboard! |
| Lighter left! | Ease to port! |
| Steering wheel straight! | Midships |
| Obsess! | Meet her |
| Keep it up! | Steady! (steady so!); Steady as she goes! |
| The right not to walk! | Nothing to starboard! |
| Do not walk to the left! | Nothing to port! |
| Edit by course! | Steer the course |
Basically, these commands should be intuitive. The commander loudly and clearly gives the command to the helmsman, after which the helmsman repeats this command and begins to execute. At the end of the execution - reports on the result if the team is working towards the goal.
For example:
To the commander: Hard - a - starboard!
Hard - a - starboard.
‹Shifts the rudder to the right until the rudder stops. Waits for the axiometer arrow to reach the maximum mark. Report. ›
Hard - a - starboard now!
To the commander: Midships!
‹Shifts the helm to zero position. The indicator hand reaches zero. Report.>
Midships now!
To the commander: Meet her! Easy.
‹Starts shifting the rudder to the opposite side of the boat's turn, reducing the angular velocity to a stop. At the moment of stopping the change - the rudder is straight, on the compass repeater the heading readings are 235 °. ›
Midships. Course two-tree-five.
To the commander: OK! Steady as she goes!
Steady two-tree-five.
The next group of commands:
It is important that, unlike the Russian language, with the English pronunciation of the numeric value of the course each digit must be separated... The number 3 (three) is usually pronounced as tree, for simplicity.
010 ° - Course ten - Zero-one-zero
082 ° - Course eighty-two - Zero-eight-two
239 ° - Course two hundred thirty nine - two-tree-nine
000 ° - Heading zero - Zero-zero-zero
Experienced helmsmen are ready to take on tasks such as keep brand, buoy, sign,
If the person at the helm is distracted from his direct task, and the command is not executed clearly:
Watch transfer
When changing the helmsmen, the man on the watch asks the commander shift permit, having received confirmation, pronounces loudly and clearly held course(gyrocompass and magnetic), gives some notes and advice on ship behavior, gives the steering wheel to the receiver and for a while to be near... Only after making sure that the new helmsman is ready can he turn over the watch. It is forbidden to transfer the watch during a maneuver.
There are some tricks that a helmsman might need to do. For example maneuver 20-20: if, in a certain situation, it is necessary to reset the speed relative to the water, and there is no opportunity for circulation, then shifting the rudder to large angles can help. To start the maneuver, stop the propeller (s), lay the rudder to one side by 20 degrees, wait for a response from the vessel, and as soon as the course change begins, shift the rudder in the opposite direction also by 20. This repetition of obsessions can significantly reduce the speed of the vessel.
Of course, the literate will come only with experience and proper work, but NavLib hopes this article will give you some theoretical knowledge and an idea of watchkeeping.
© NavLib copying materials without an active link to the site is prohibited.
Ensuring the turnability of the ship is achieved by using the controls and movement of the ship. depending on the design and the nature of their use, the controls are subdivided into main (GSU) and auxiliary (APU). The action of the GSU depends on the speed of the ship or on the nature of the propulsion system. The main controls are rudders different types and rotary attachments.
Auxiliary controls are propulsion and steering systems, the action of which is not associated with the operation of the ship's main engines. Auxiliary controls include thrusters (PU), active rudders (AR), retractable propelling and steering columns (VDRK) and rotary columns (PC). Under certain conditions, on some projects of ships and submarines, auxiliary controls can also be used as the main means of propulsion.
Main controls. Rudders and their geometric characteristics
The ship's rudder is a wing with a symmetrical profile. According to the method of connecting the rudder blade with the ship's hull, rudders are simple, semi-suspended and suspended, according to the position of the stock axis relative to the rudder blade - unbalanced and balanced (Fig.1.1). Only balanced or semi-balanced rudders are installed on ships. The ratio of the area of the balancer part of the rudder to the rest is called the rudder compensation coefficient. It usually ranges from 0.2 to 0.3. The most important geometric characteristics of the rudder: its area Sp, relative elongation λр, shape and relative thickness of the cross-sectional profile Δр.The rudder area Sp is on average about 2% of the immersed area of the center plane (LxT).
The relative elongation λр = h²p / Sp, where hp is the height of the rudder blade, usually ranges from 0.4 to 2.5.
Rice. 1.1. Rudder classification
The relative thickness of the profile of the cross-section of the rudder Δр = lp / bр, where lр is the greatest thickness of the profile, and bp is the average width of the rudder, usually equal to 0.15-0.18.
The height (span) of the rudder, hp, is usually determined by the conditions for its placement in the aft clearance.
On single-rotor ships, one rudder is installed, which is located behind the propeller.
Twin-screw and three-screw ships can have one or two rudders. In the first case, the steering wheel is located in the center plane (DP), and in the second - symmetrically behind the side screws.
The position of the rudder relative to the incoming flow is characterized by the rudder shift angle ap and the angle of attack a.
The rudder shift angle ap is the rudder rotation angle measured in a plane perpendicular to the stock axis. ar of sea vessels is usually limited to 35 °. The angle of attack of the rudder is called the angle formed by the plane of symmetry of the rudder and the plane passing through the axis of the stock and coinciding with the direction of the incoming flow.
Rice. 1.2. Propulsive handlebar trim
To increase the propulsive efficiency of the propeller, propulsive (pear-shaped) trims are sometimes installed on the rudders (Fig. 1.2). The positive effect of propulsion pads is reduced to equalizing the associated flow and reducing turbulence during the operation of the propeller.
Swivel nozzles are a propeller guide nozzle mounted on a vertical stock, the axis of which intersects with the axis of the propeller in the plane of the propeller disk (Fig. 1.3). The rotary guide nozzle is part of the propulsion system and at the same time serves as a control element, replacing the steering wheel.
The nozzle removed from the DP works like an annular wing, on which a lateral lifting force arises, causing the ship to turn. The hydrodynamic moment arising on the nozzle stock (both forward and reverse) tends to increase the angle of its shifting. To reduce the influence of this negative moment, a stabilizer with a symmetrical profile is installed in the tail of the nozzle.
Rice. 1.3. Swivel nozzle
Auxiliary controls
The active rudder (Fig. 1.4) is a conventional rudder with an auxiliary propeller installed on it in a short nozzle. The screw is driven by an electric motor housed in a sealed housing.The power of the electric motor is about 8-10% of the power of the main power plant, and the diameter of the auxiliary screw is taken equal to 20-25% of the main one. The active rudder ensures the movement of the ship at a speed of 3-4 knots. Its most effective use is in the mode close to the mooring. Such a rudder provides a turn of the ship without a move, practically in place. The drive of the active rudder allows it to turn relative to the ship's DP up to 70-90 °. When the electric motor is off, the active steering wheel acts as a normal one.
Rice. 1.4. Active steering
The thruster (Fig. 1.5) is structurally a cylindrical pipe 3 in the ship's hull with a propulsion unit 1 placed in it, capable of creating thrust in two opposite directions perpendicular to the DP.
Rice. 1.5. Schematic diagram bow thruster with main counter-rotating propellers
The leading edges of the channel are rounded to increase the effectiveness of the PU. Protective grilles are installed at the entrance of the PU 2. Power from the engine 4 is transmitted through the vertical shaft 5, the bevel gear 6 and the horizontal shafts 7. By the type of propellers, thrusters are distinguished with propellers (fixed pitch propeller - fixed pitch propeller and variable pitch propeller - CPP), vane propeller or reversible pumps. Usually the bow thruster is located in the bow or stern.
Rice. 1.6. Schematic diagram of a retractable steering column
Sometimes two devices are used - bow and stern. As operating experience shows, the effectiveness of the thrusters decreases sharply with an increase in travel speed.
Retractable propulsion and steering column (Fig. 1.6). The propeller in the VDRK is the screw 1, located in the guide nozzle 2. Power to the screw is transmitted from the electric motor 3 through the vertical shaft 4, the upper cylindrical gearbox 5, the vertical splined shaft 6 located inside the column stock 7, and the lower angular gearbox 8. Turning mechanism 9 provides a turn of the screw-nozzle complex at any angle. The lifting and lowering of the complex is carried out using the lifting mechanism 10 in the form of a telescopic hydraulic cylinder.
The rotary columns are similar in principle to the VDRK, but they do not have a lifting mechanism. In some cases, folding pivots are used.
Of the SPGs listed above, VDRKs are the most effective: They can be removed while the ship is moving and do not create additional resistance.
The efficiency of any ACS is characterized by specific thrust, i.e. thrust per unit of consumed power. Usually it is at least 10 kgf / l. with. ACS can be used both in conjunction with the main propulsion and steering complex, and independently. They are widely used for mooring, turning in tightness with no progress and low moves.
The action of the rudder and the hydrodynamic forces arising on it
When the rudder is shifted to an angle αp, an area of increased pressure arises on its front plane due to a decrease in the flow velocity. On the back plane, where the flow rate increases, the pressure decreases. The pressure difference leads to the emergence of the resulting hydrodynamic force Rp, directed almost perpendicular to the plane of the rudder blade and applied in the center of its pressure.The Rp value depends on the area of the rudder blade, the angle of attack, and is approximately proportional to the square of the speed of the water flowing onto the rudder.
To consider the action of the rudder, the resultant Rp is decomposed into components in the coordinate axes invariably associated with the ship: Rpy (lift), Rpx (drag) and the components Rpn and Rpt relative to the stock axis (normal and tangential, respectively) (Fig. 1.7).
Rice. 1.7. Hydrodynamic forces acting on the steering wheel
Hydrodynamic forces are related to the resultant and to each other by the following relationships:
The action of the steering wheel in the forward motion (Fig. 1.8, a). Shifting the steering wheel in the forward direction is accompanied by the appearance of the lateral hydrodynamic force Rpy. Applying two equal and opposite forces Rpy in the center of gravity of the ship G, the moment Rpyl is obtained. The action of the moment RPyl is accompanied by a reverse displacement of the ship and the appearance of a drift angle α. The presence of the drift angle leads to the formation of a lateral force Fy, applied at the center of the ship's drag and reversed in the direction of Rpy. Thus, the turning moment during the forward movement of the ship is determined as the sum of the moments from the forces RPy and Fy:
Rice. 1.8. Forces acting on the ship when shifting the rudder
The action of the steering wheel in reverse (Fig. 1.8.6). When reversing, the rudder shift also causes the RPy to appear, the RPyl moment and the ship drift. The appearance of the drift is also accompanied by the appearance of the force Fy and the action of the moment Fyx. However, the action of Fyx is opposite in the direction of action of Rpyl.
Thus, the turn of the ship in reverse will occur under the influence of the moment difference;
Therefore, the controllability of the ship under the action of the rudder in reverse is much worse than in the forward direction. Coming out of steady circulation reverse using a single rudder is almost impossible.
The moment of the resultant relative to the stock axis is called the hydrodynamic moment on the stock. Its value is determined by the dependence
where a is the distance of the stock axis from the leading edge of the rudder;
Xp is the distance of the center of pressure from the leading edge of the rudder.
Rice. 1.9. Hydrodynamic moments on the stock of a simple and balanced rudder
At a balance rudder (Fig. 1.9), at small angles of shifting, the center of pressure is located in front, and at large angles, it is behind the axis of the stock. With a simple rudder, as the shift angle increases, the center of pressure moves away from the axis of rotation all the time. This leads to a constant increase in the hydrodynamic moment on the stock. At the same time, a high-power steering gear is needed to shift the steering wheel.
Ship circulation
When the rudder is removed from the DP at a certain angle, the ship will begin to make curvilinear motion along an open spiral-type curve. The trajectory described by the ship's center of gravity (CG), in this case, is called circulation (Fig. 1.10).
Rice. 1.10. Ship circulation
When the movement of the ship is established, the circulation becomes a circle. The diameter of this circle is called the circulation diameter Dc.
Circulation curve characteristics:
Extend l1; - the distance traversed by the ship's center of gravity in the direction of the straight course from the moment the rudder was shifted to a 90 ° turn; the value of the extension varies in the range of 0.6-1.2 Dc;
Forward displacement l2 is the perpendicular distance to the initial course, by which the ship's center of gravity shifts towards the circulation at the moment of its rotation by 90 °; the value of the forward bias varies within 0.25-0.50 Dts;
Reverse displacement l3 - the greatest distance by which the ship's center of gravity is displaced from the direction of the initial course in the direction opposite to the circulation; the amount of reverse displacement usually does not exceed the half-width of the ship;
Tactical diameter DT - the shortest distance between the position of the center line of the ship on the initial and return courses; the size of the tactical diameter usually ranges from 0.9-1.2 Dc;
The circulation period T is the time it takes for the ship to complete a full 360 ° turn. The circulation period depends on the speed of the ship and is approximately 3-5 minutes.
To assess the ship's turnability, the relative circulation diameter is used, which is determined from the ratio Dc / L. Its value for high-speed ships usually ranges from 4-7.
When studying circulation, it is conventionally divided into three periods.
The maneuvering period lasts from the beginning to the end of the rudder shift (10-15s).
The evolutionary period begins from the moment of the end of the rudder shift until the ship turns 90-180 °, when the forces acting on the ship come to equilibrium. After this, a period of steady circulation begins, which continues until the position of the rudder is changed.
Roll of the ship on the circulation
Shifting the rudder on a ship following a straight-line course leads to a curvature of the trajectory in the direction opposite to the rudder shift. As a result, centrifugal force arises, the moment of which causes a slight roll to the side where the rudder was shifted.This roll is also due to the moment of lateral force acting on the steering wheel. As the curvature of the trajectory changes, the centrifugal force first decreases and then increases. Under the action of the moment of this force applied to the ship's CG, the ship begins to roll in the direction opposite to the direction of the rudder shift, and the first inclination of the ship is the greater, the greater the roll angle it had towards the rudder shift (Fig. L.ll).
Rice. 1.11. Forces heeling the ship on a steady circulation
The maximum inclination of the ship in the direction opposite to the direction of the rudder shift is called the dynamic bank angle. Typically, the dynamic roll angle exceeds the roll at steady-state circulation by 1.3 to 2 times. The maximum value of the roll angle at steady circulation is determined by the formula of G.A. Firsov:
Where V0 is the speed of the ship on a straight course before the start of circulation, m / s;
T is the average draft of the ship, m;
H - initial transverse metacentric height, m;
L is the length of the ship, m; Zg is the ordinate of the ship's center of gravity, m. It follows from the formula that under certain conditions it is dangerous to circulate at high speed. It is especially important to take this into account when sailing on favorable waves and when making a turn to the wind.
Center of rotation of the ship
The character of the ship's movement on the circulation is determined by the position of a point on its diametrical plane, the drift angle of which is β = 0.
Rice. 1.12. Center of rotation of the ship
Geometrically, the position of this point is determined by the intersection of the ship's DP with the perpendicular lowered to it from the center of circulation (Fig. 1.12). This point is called the ship's center of rotation. Its position along the length of the ship is characterized by the Lcvv-Rβo value. Distance lcv, expressed in fractions of the ship's length L along the waterline:
The absolute value of this value at rudder shift angles exceeding 20 ° lies within
The center of rotation always lies at the nasal tip. Hence follows an important practical conclusion that control of the ship in turns is carried out by moving its stern. This must be constantly taken into account when mooring a ship, passing narrows and navigational hazards.
Steering wheel commands. Turning order
"The ship commander assigns the ship's course and speed through the officer in charge." In some cases (when determining the maneuverable elements, instrument corrections and narrow navigation), by the decision of the ship commander, the right to directly command the rudder may be given to the navigator.To successfully complete turns using the rudder, the ship commander, navigator and officer of the watch must know the following information:
The diameter of the circulation when the rudder is shifted to different angles to the right and to the left under different operating modes of the main machines;
The time to describe the complete circulation and its part at various speeds and combinations of operating machines;
Loss of speed on circulation when the rudder is shifted to a set number of degrees for different travel speeds;
- "dead interval" of time from the moment the command is given to the helmsman until the start of the actual turn;
Possible value of the roll angle of the ship on the circulation, depending on the speed of the course.
When performing a turn, they are guided by the following rules:
Before giving a command to the steering wheel, it is necessary to assess the situation and take all measures to safely perform the maneuver;
You should resort to shifting the rudder "on board" only if absolutely necessary (when the ship turns in a narrow space, to avoid collision with another ship, to avoid the detected navigational danger and enemy attacks);
It is necessary to ensure the possibility of a quick transition to spare steering positions;
When sailing together, the turn of the ship must be indicated by an installed flag or light signal from the moment the command is given to the rudder until the end of the turn;
When changing the course in the formation of the wake, the turn should be carried out so that the stem goes along the inner edge of the wake of the ahead matelot.
The steering wheel commands must be given in strict accordance with the "Command Words" (annex to the Naval Regulations of the Navy). The helmsman must rehearse the given commands in a loud voice, preceding them with the word "Yes".
The following basic steering wheel commands are accepted:
Command "Right (left) aboard" means that the steering wheel should be put to the set limit in the indicated direction. The command is given taking into account the rapid shift of the rudder.
By command "Right (left) rudder" the helmsman is obliged to shift the rudder to the specified number of degrees (for a given ship) in the indicated direction and report: "Rudder to the right (left) so much". During the turn, the helmsman reports new heading values every 10 °. This command is issued when performing normal turns to a new course and joint maneuvering with ships of the same type.
When turning with a larger or smaller than usual diameter of the circulation, the command “So many degrees of right (left) rudder” is issued.
Command "Take away" served when the ship approaches the designated course (usually by 10-15 °). At this command, the rudder is retracted into the ship's DP, after which the helmsman reports: "The rudder is straight." Similar actions are performed on the command "Straight rudder". The command is given when it is necessary to interrupt the execution of the turn. After the commands "Retract" and "Straight rudder" the helmsman reports the course every 3 °.
Command "Obsess" served when 3-5 ° is left before the appointed new course. At this command, the steering wheel is shifted a small number of degrees to the side opposite to the circulation. The helmsman reports the compass heading every degree.
Command "Keep it up" means that the helmsman must notice on the compass with an accuracy of a degree the course on which the ship was lying at the time of command, or the direction along the coastal landmark and keep the ship on this course, reporting: "Yes, keep it up, there are so many degrees on the rumba." ...
Request command "On the rumba" means that the helmsman should notice the compass heading and report: "There are so many degrees on the rumba."
Command "So many degrees to the right (left) according to the compass" means that the helmsman must change the course by the indicated number of degrees, and then report: "There are so many degrees on the bearing." The command is given in cases when it is necessary to change the course of the ship by no more than 15-25 °.
An experienced helmsman can be given the following commands: “Right (left) rudder. The course is so many degrees "; "Keep in the wake of such and such a ship"; "Lie on target"; "Leave such and such an object to the right (left)", etc.
In this case, the helmsman independently performs the indicated actions and reports: “On the alignment. There are so many degrees on the rumba ”or“ There are so many degrees on the rumba ”, etc.
Using autopilot
In recent years, to automate control of a ship on a given course, the main means of steering are automatic course stabilizers (autopilots). Compared to manual heading, automatic heading control facilitates the work of the helmsman and provides more accurate heading, reduces yaw and ensures that the desired turns are performed. The use of an autopilot allows for the use of a software device or a remote control system. Two modes of operation are possible depending on the tasks performed by the autopilot.2. Control mode. In this mode, the autopilot must ensure a change in the direction of movement of the ship in accordance with the requirements of the operation. In this case, the change in the heading angle can be performed using software control (according to a predetermined law) or using a remote control system. System automatic control heading usually consists of an object of regulation and an autopilot (regulator). The object of regulation is a ship, the heading angle of which is a controlled value, and the rudder deflection angle ap is a control action. The autopilot functions are performed by a special tracking system that provides steering deflection.
1. The sensor of the actual course Кгк provides measurement of the sign and magnitude of the misalignment (deviation of the ship's course from the set value), as well as the issuance of a control signal. The functions of the sensing element are usually performed by a gyrocompass.
2. The software device - the preset heading sensor - provides programmed heading control, which can be set manually, by a rigid program (zigzag), or by a ship's computer.
3. The misalignment sensor is used to generate control signals when the ship deviates from a given course.
4. The amplifier-converting device provides amplification of the control signal and the generation of corrective signals that take into account the speed of the ship's departure from the given course and the systematic one-sided deviation of the ship from the given course under the influence of various factors (wind, waves, partial operation of machines, etc.).
Rice. 1.13. Schematic diagram of the autopilot
Usually, the amplifier-converting device provides for the adjustment of the autopilot parameters (sensitivity, feedback coefficient, etc.) according to the maneuvering elements of the ship and the actual sailing conditions.
5. The actuator (steering gear) has a main negative feedback sensor designed to improve the quality of automatic steering control (provides damping of ship oscillations around a given course - Kzad).
(2) Semi-suspended balanced rudders are called semi-balanced rudders.
(5) KU-59 (Military Publishing, 1967), Art. 830.2-17
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