5.3. Features of the operation of inflatable boats.
So, the boat is prepared for sailing. How to exploit it? Let us first dwell on the general issues of the operation of inflatable boats. Any voyage begins with a departure from the coast. Unfortunately, many boat owners tend to quickly begin a tourist trip, reach the treasured backwater, cast a fishing rod in a favorite place and. lose vigilance when moving offshore. But it’s a pity, because the bottom of reservoirs, especially unfamiliar ones, is sometimes covered with broken glass, metal cans, driftwood. The most dangerous are the remains of shrubs that died from bitter-salt water in the water bodies of Central Asia. In the summer months, the water level in these reservoirs decreases as a result of intense evaporation of water. As soon as the water leaves, dead bushes with a powerful root system come to life, giving rise to young growth. In the fall, when this shoot comes under water, it dies, leaving hard knots that pose a danger to the shell of an inflatable boat. Increased attention is also necessary when passing rafting rivers and rivers that become shallow during the summer. They, as a rule, are littered with logs, snags, and topliki. When meeting such items, the boat may be damaged. A similar situation may occur when returning back.
Mooring and mooring is best done against the tide. In calm water, this is done in one smooth turn, on the turbulent river, backwaters should be used for rocks, and ledges of the shore. With strong excitement, landfall and departure from it seem to be the most difficult stages of the journey. To conduct them, you need to choose places in shallow water with sandy and pebble beaches, and not near rocky or rocky shores.
Therefore, the following should be remembered: Depart from the shore and approach it should be slowly, carefully, carefully inspecting the bottom of the reservoir.
When swimming, it is also important to be careful, especially in shallow water in unfamiliar and clogged bodies of water, and to monitor objects sticking out of the water. If you need to change places in the boat, then you need to do this slowly, so as not to bank the boat. Changing places in an unstable boat is only necessary near the shore. The boat should be located only on regular seats; placement on board can lead to the turning of the boat. Going from boat to boat is necessary without sudden movements. You can not jump from a boat to the shore or the bridge, since a person, when jumping with support on the borg, will push it to the side and will be in the water due to the insignificant mass of the boat.
Due to the low draft, large area of sail and small mass, inflatable rowing boats, especially small ones, are subject to drift under the influence of wind and waves, therefore, in large open water bodies dominated by wind and waves, care must be taken to monitor the strength and direction of the wind and wave height. The degree of excitement and wave height can approximately be determined visually by the characteristic features of the water surface (tab. 5.1). Each owner must know the permissible wave height indicated in the Owner's Manual for his boat and, depending on it, decide on the possibility of operating the boat.
The most dangerous wind in the water bodies of Central Asia. A rare day here is calm. A strong wind creates large waves, which in deep places can be gentle, and near the shore they become high, forming a surf. It should be borne in mind that in a strong wind, especially blowing from the shore, at a significant wave height it is very difficult to row in an inflatable boat. In this case, it is better to turn the boat forward or aft to the wave.
The height of the waves in the reservoirs usually reaches 2.5 - 3.0 m, in the lakes 3.5 m. On the rivers and canals, the wave height is usually less than 0.6 m, but sometimes (usually during the spring waters) it can reach 1 m When weather conditions worsen, the most prudent is to stay close to the shore. Small rowing boats should not be operated far from the coast at all. It is not recommended to use inflatable boats in the fairway zone of reservoirs, especially in the dark and during fog. But if you still have to swim in such conditions, then you must have a signal color electric lamp.
Consider the specific features of the operation of rowing, motor and sailing inflatable boats.
When rowing in an inflatable boat, an oar with support on board, the rower sits with his back to the movement, and when rowing by rowing - the same as on an inflatable kayak, facing the movement. Coverage of the oar handle with your fingers should be free, without tension. To create emphasis during rowing, the legs are slightly bent at the knees and rested on the inflatable side, seat, support ledges or lead under the side. Any person can use an inflatable boat with a certain skill and rowing skills. Since the inflatable boat has a tendency to yaw and drift, rowing should be done with short strokes, since in this case it easily glides on the water and is better held on course.
If for some reason the boat is sailing alone offshore, in a strong wind or in a fast current, it is recommended to tie the end of the bow of the nose to the body, because if a person accidentally falls into the water, the boat can quickly be carried away from it.
Everyone who uses an inflatable rubber boat knows that at one anchor it is very unstable, it is “carried” by the wind, and the installation of two anchors is difficult. Nevertheless, there is a reliable single-anchor version of the boat. To do this, the halyard is passed into the side rings on the cylinders and tied so that a triangle forms with a side length of approximately two meters. An anchor is attached to the free end of the halyard. Moving the halyard in the rings, they achieve the desired position of the boat in which it will be held by the wind or current. As a result, it becomes possible to place the boat at different angles to the wind or current and thereby increase, for example, the area of fish catch.
A person with the skills to control a rigid motor boat can easily drive an inflatable motor boat, the characteristic features of which are a small inertia of movement and a small circulation radius of 2 to 3 lengths of the boat hull, as well as great sensitivity to the placement of cargo along the length of the cockpit . When accelerating, an inflatable motor boat, as a rule, acquires a significant trim in the stern. The angle of the running trim during acceleration on motor boats with engines of 14.7 - 22.1 kW (10-15 hp) reaches 30 °, and the observers at the first moment get the impression that now it will turn over, but it will pass quite a bit time, and the boat quickly goes on planing. When gliding, the angle of the running trim does not exceed 1 ° 30 'and the boats literally “creep” through the water.
On fig. 5.14 and 5.15 dependences of the running trim angle and speed on the rotor speed of the motor for the Orion-8 and Orion-15 inflatable motor boats equipped with the Veterok-8 and Veterok-14 motors with standard propellers and two on board the passenger. As can be seen from the figures, the trim, having reached a maximum in the swimming mode, begins to decrease sharply in the transition mode and becomes minimal and constant in the planing mode. The stable planing mode for the Orion-8 boat starts at 4000 1 / min, and for the Orion-15 it starts at 3500 1 / min.
When operating an inflatable motor boat, it should be borne in mind that due to the low inertia of the course when the engine is stopped instantly, the stern wave can catch the boat and sweep it through the cutout in the transom. Therefore, the braking of inflatable boats must be carried out smoothly, gradually resetting the engine speed. You should not keep the boat heading straight for big waves, it is better to alternate one or the other side at an angle to the wave. Turning is necessary to carry out smoothly, slowly reducing the engine speed, since during a sharp turn, water escaping from under the end of the cylinder that is external to the turn hits the inner cylinder and floods the boat through the transom.
Loading, power and engine speed affect the speed of a motor boat (see fig. 5.15). An increase in motor power invariably gives a speed increase in any load case. At the same time, a change in load significantly affects speed only on boats with low power motors. On boats with medium and high power motors, the load has a smaller effect on speed, since their power quite enough to provide gliding even at full load. Heavy-duty inflatable boats with powerful engines allow you to develop high speed with one or three passengers on board, but with a further increase in load, their speed drops significantly.
The owner of an inflatable motor boat must clearly understand how the speed, fuel consumption, engine life, distance traveled are related, and correctly choose their optimal ratio, depending on the goals and operating conditions. The increase in speed is not always proportional to the increase in speed, distance traveled and fuel consumption.
Although inflatable boats in the efficiency of using sails can not be compared with rigid boats, they are quite suitable for tourism and recreation, holding regattas of various ranks. They can learn all the rules of sail management. However, for successful sailing on an inflatable sailing boat, even the smallest, with the simplest sailing weapons, special training is required.
Sailing boat is controlled by sheets and rudder or steering oar (Fig. 5.16). The steering wheel can keep the sailing boat on course, change course by shifting the steering wheel from the diametric plane to the port or starboard side, or turn or slow down the movement of the boat. The effectiveness of the steering wheel is determined by the speed of the boat and the angle of deviation of the steering wheel from the diametrical plane. Any deviation of the steering wheel, causing a braking effect, reduces the speed of the boat. Shifting the rudder to an angle greater than 20 ° reduces the speed of the boat significantly, therefore, when controlling a sailing boat with the help of the rudder, you should choose the optimal angle of its deflection so that at a given speed you can clearly perform a maneuver with minimal loss of speed.
An inflatable sailboat, like any other sailing vessel, cannot go directly against the wind, for this you need to resort to maneuvering. Depending on the sailing equipment, the boat can go in the following courses (Fig. 5.17): fordewind (tailwind wind blowing into the stern), gulfwind (wind blowing directly into the side), backstag (wind blowing into the stern at an acute angle), bedevind (wind blowing into the nose at an acute angle). At all courses, except fordewind, an inflatable boat drifts and rolls, which is inherent only to a boat with a sailing propulsion. The speed of an inflatable sailboat depends on the strength of the wind, the course of the boat relative to the wind, the design and type of sailing weapons, sail area and steering ability.
It is difficult to give advice on controlling an inflatable sailboat with different types of sails, however, you can list a few basic rules that the helmsman needs to remember before raising a sail on an inflatable boat. Before operating a sailing boat, it is recommended to pre-test sailing armament under the guidance of an experienced yachtsman, who will help to master the subtleties of control and eliminate the design flaws of the selected sail. To reduce the windage it is necessary to transfer the boat to the water with a lowered sail. Before sailing, it is necessary to check the fastening of the steering wheel, shverts, knots of fastening of sheets and files. Having sailed from the shore with the help of oars to a depth at which you can put the shverts, the oars must be put in the cockpit so that in an emergency you can quickly put them in motion.
Sail can not be raised high above the side to prevent the boat from tipping over in strong gusts of wind. When controlling the sail, the sheets must always be straightened, they should be held in hands, not winding or fastening to the details of the boat's hull, otherwise a sudden strong gust of wind could put the boat on the water. If a gust of wind strongly heels the boat to one side, then it is necessary to etch (loosen) the sheets, partially de-winding the sail, fasten the halyards, carefully stacking them so that in the event of a strong gust of wind or an emergency they can be instantly returned, i.e., lower the sail . Sailing is necessary so that they are always filled with the wind, and not rinsed (clapped) in the wind. People should be accommodated in the boat from the windward side (from the side where the wind blows from) and sit as low as possible.
In a sailing trip, weather conditions to a greater extent affect the passage of the route than in other water trips. The wind is not only a driving force, but also determines the state of the surface of the reservoir. Therefore, the development of the route is impossible without studying the windwave regime in the water area. Each section of the reservoir is characterized by its own winds. The nature and direction of the winds are determined on special maps by a wind chart called a wind rose. When swimming, especially in shallow water and when approaching the shore, you need to monitor the depth in order to remove the curtains and steering wheel in time. Since the direction of the wind, especially near the shore and in inland waters, never remains constant, it is necessary to have a pennant that will help you choose the right course when changing the direction of the wind. For safety reasons, inflatable sailboats are recommended to be operated in light, moderate and rarely fresh winds. Roughly the strength and speed of the wind can be determined on a scale for visual assessment of wind strength (tab. 5.2).
To determine the wind speed in the measurement range from O to 44.8 m / s with an accuracy of ± 3%, or ± 0.1 m / s, an electronic anemometer is produced in the United States as a turbo meter, which is a combination of a pocket calculator and a sensitive turntables - turbines that rotate in sapphire bearings. The speed of the turntable is measured and converted into digital readings on the display of the device. The device is powered from three small-sized elements with a voltage of 1.5 V. The dimensions of the turbometer are 118 x 66 x 29.5 mm, weight 85 g.
Inflatable boats, converted by amateurs into sailing boats and without a rudder and elements that reduce drift, can be used only with a weak or moderate tailwind blowing in the stern (fordewind course), since the wind blowing from the side and at an angle will cause strong drift and may tip the boat.
The movement of inflatable boats under sail at night is unacceptable. Each crew member of a sailing inflatable boat must be in a life jacket.
Any boat, including an inflatable boat, is not insured against possible damage and overturning. If the shell is damaged (a small puncture, cut, rupture, etc.), leading to a breach of tightness and a decrease in the buoyancy of the boat, people sitting in the boat need to remain calm. The first minutes after the accident are always the most unpleasant: it seems that the air is rapidly leaving not one compartment, but not enough to keep the boat afloat from the entire inflatable balloon and the remaining volume of air in intact compartments. This is actually not the case. After a few minutes, air no longer escapes from the damaged compartment, since the difference between atmospheric pressure and the pressure inside the side is negligible. In other intact compartments, the pressure remains almost unchanged and can only decrease due to the bending of the partition to the other side.
If an accident occurs, first you need to find out the cause of the air leak, the nature of the damage and decide on the place and time of the repair. With minor damage, you can reduce air leakage by covering the hole with a rubber stopper or a temporary patch of adhesive tape, and continue swimming until the first parking lot, where it is convenient to make repairs. In case of serious damage to one of the compartments, a noticeable pressure drop occurs in the entire chamber.
To ensure unsinkability, for example, of a small rowing boat with two compartments formed by vertical partitions, the damaged half must be bent into the inflatable seat inside the boat: it serves as a bridge preventing water from entering the boat. If possible, you should be careful not to pull out the filling valve, pump up entire compartments.
If the bow compartment of an inflatable motor boat with a keel and wooden floorboards, which give it longitudinal and lateral rigidity, is damaged, to ensure unsinkability, one must also bend the bow, slow down the speed of rotation of the propeller, and properly differentiate the boat so that water does not overflow through the bow. If the stern compartment of a U-shaped motor boat is damaged, you can get to the shore under the engine at a low speed. On O-shaped boats, in a similar case, it is better to remove the engine from the transom, put it in the cockpit, move the gas tank and heavy things from the stern to the bow and sail to the shore with oars.
If the inflatable hull of the sailing boat is damaged, you must immediately lower the sail, raise the curtains or the daggerboard and keep heading towards the shore.
Если вода поступает в кокпит через пробоину в днище, надо принять меры, чтобы уменьшить поступление воды, закрыв повреждение надувным сиденьем или другим подходящим предметом. Вместе с тем не следует проявлять особое беспокойство, так как при соблюдении требований к грузоподъемности лодки уровень воды не превысит половины высоты борта, что позволит без особого труда довести лодку до берега.
When turning over the boat, which happens more often on tourist trips, you must first try to return the boat to its original position. To do this, grab the board that is farthest from you with your hands on top of the bottom and jerk it toward you, and if the boat does not roll over, then you need to hold onto the boat rail or climb to the bottom to swim with it to the shore.