The question of what the name of a boat floating above the surface of the water in the air layer is often controversial among beginners and even experienced water engines. In everyday speech, you can hear different options from simple "amphibian" to complex technical terms that confuse the essence of the design. hovercraftOr, if you are talking about small size, hover-cushion.
The main thing about these vessels is the way they're propelled and kept afloat. Unlike the classic boats, which displace water with their hulls, they use injected air, which allows them to navigate not only water barriers, but also land, ice or marshy terrain, and it's this versatility that makes them a unique class of technology in a boating environment.
In this article, we will discuss in detail the physics of the process, the types of engines used and the design features. The pillow is created under the bottom.It's not on the sides, and how that affects handling, and we're going to talk about maintenance and safety in real-world environments.
Terminology and classification of boats
The first thing you need to learn is to clearly distinguish between concepts. hovercraft (SVP) But in aquatic motors, the term amphibian is often used, although it's not exactly a classification term, amphibian is a capability, not a propulsion type. ekranoplanesThey use the aerodynamic lift of the wing rather than the static air pressure under the body.
Classification of airbags is usually based on the type of airbag scheme. The most common chamber scheme, where air is pumped under a flexible fence; there are also nozzle and slot circuits, which are more often used on large boats or specialized equipment; for private water-motor use, it is the chamber variants with flexible fencing that are most relevant.
It's important to understand the difference between a VVR and a glitter boat, and the plane only rises above the water at high speed because of dynamic pressure, whereas the air cushion lifts the body before it even starts, which gives a tremendous advantage when starting and driving through shallow water or grass.
⚠️ Warning: Do not confuse a hovercraft with a hydrofoil, the latter being generated by the movement of water relative to the submerged wings, not by air.
There's a lot of variation in models, and it depends on what you're looking for, and if you want to be able to walk on ice and dirt, it's a SVP. If you only have to be able to run on clean water, you might want to consider traditional glittering options.
Operating principle and propulsion device
The basis of any IFR is an air injection system, and it's sucked in through the inlet and pushed down under the bottom, so that it doesn't escape immediately, it's used to keep it from flowing out. flex-fence It's the skirt that forms a closed volume, which creates an excess pressure that lifts the body.
The forward movement is carried out by a separate traction engine or propeller. Often a two-engine scheme is used: one works on the injection (cushion creation), the second - on the traction. In simpler and cheaper models, one engine can be used with power sharing through the transmission, but this reduces efficiency.
The design of the skirt requires special attention, it is made of durable, elastic materials that are resistant to abrasion and ultraviolet light. Damage to the skirt leads to loss of pressure and the inability to detach the body from the surface. Modern models use sectional skirts that are easier to repair.
Why does the skirt wear out faster than the body?
The skirt is in constant contact with surface irregularities (waves, rocks, grass), friction and dynamic loads lead to rapid wear of the material, so this is the most consumable part of the IFR.
The direction of travel is controlled either by turning the traction screw or by using air rudders located behind the screw, and the rudders redirect the flow of air, causing the stern to shift in the right direction.
Types of engines: gasoline, electricity or gas?
The power selection plant is critical. High power specific engines are required to create sufficient pressure and thrust. Traditionally, gasoline engines, often converted from car or motorcycle units, are used to provide the necessary traction, but they are noisy and require regular maintenance.
Electric motors are gaining popularity because of the quietness of operation and the absence of exhaust gases. However, their main enemy is the weight of the batteries. For a SVP, every extra kilogram reduces lift height and cross-country ability. So electrification is still relevant only for light single models with short battery life.
Gas turbine engines are used on large and high-speed models, they are very powerful and lightweight, but their cost and fuel consumption make them a lot of professional equipment or sports, for recreational fishing or recreation, this is redundant and economically inefficient.
When choosing a gasoline engine for a VPS, prefer air-cooled models that are lighter than water-cooled models and do not require complex cooling systems, which is critical for the weight of the vehicle.
The table below compares the main types of engines used in amateur shipbuilding:
| Type of engine | Power | Weight. | Noise | Applicability |
|---|---|---|---|---|
| Gasoline engine | High. | Medium. | High. | Universal. |
| Electric motor | Low/Medium | High (batteries) | Low. | Small distances |
| Gas turbine | Very high. | Low. | Very high. | Sport/Profi |
Advantages and disadvantages of operation
The big trump card of the SVP is permeabilityThe boat can go ashore, drive on sand, mud or ice, making it ideal for rescue, hunting and fishing in hard-to-reach places where the usual topping up engine is powerless.
But there are some significant downsides, and noise is the first, because being on an open platform next to the engine and propeller requires the use of headphones, and wind is also a problem, because of the large sailing and the lack of contact with water, it becomes difficult to control high winds.
The fuel consumption of a SVP is generally higher than that of a similarly sized glitter boat, and the engine has to be constantly running to keep the cushion running, even if you're standing still. Unlike a normal boat, where the idle engine is running idle, here it does weight retention work.
The cost of ownership is higher, too, and the resource of a full-rotor engine is reduced more quickly, the skirt needs to be replaced or repaired after a certain number of hours, and all of this needs to be considered when planning your budget.
Features of management and security
The control of the SVP is very different from the control of the boat. There is no rudder in the classical sense (unless there is a sub-rig, which is rare for clean SVPs), the rotation is carried out by relaying the air rudders, the efficiency of which depends on the speed of air flow. At low speeds, the boat hardly obeys the steering wheel.
The inertia is very high, and you can't stop it instantly because there's no brakes on the water, and you can do it by turning against the wind or by using a traction screw reverse if you can, and you need skill and foresight.
Safety of passengers is a priority. An open screw in the rear poses a danger. All passengers must be inside the fence or behind safety nets. Exiting the hull on the move is strictly prohibited because of the risk of being hit by the screw or being dropped by airflow.
⚠️ Attention: When driving on ice or rocky surface, the speed should be minimal. A sharp impact on an obstacle can damage the skirt or bottom, leading to instantaneous loss of buoyancy and tipping.
Maintenance and repair DIY
Owning a SVP means being ready for frequent maintenance. An engine that works in dusty or wet conditions requires regular filter replacement and candle checks. Pay special attention to engine mounting - hover vibrations are transmitted to the body more strongly than on water.
The skirt is the most vulnerable element. Small punctures can be sealed with special compounds for PVC or rubber right on the spot. Serious tears require patching or replacement of sections. It is a mandatory rule to have a remix for a skirt.
Checking the air duct seal is also important, because cracks in the body or loose connections cause pressure loss, and you can use a soap solution to diagnose it by applying it to the joints with the supercharger running.
☑️ Daily maintenance of MRAs
Comparison with traditional PVC boats
Many people wonder whether to switch from a conventional inflatable boat to a SVP? PVC boat is cheap, compact when folded and silent (if rowing or using a low-power electric motor), but it does not have the cross-country speed and speed that an airbag gives.
The VVP is a winner in speed and overgrown water, and Tina and algae are not coiled onto the propeller because it's in the air, but the VVP is a loser in terms of size when transported (you need a trailer or a roof of a car) and in price.
The choice depends on the geography of your exits. For a quiet fishing on a lake with a hard shore, the classic is better. For expeditions to swamps, shallow waters and ice, only SVP.
A hovercraft is a specialized tool for challenging conditions, not a universal replacement for a regular boat for weekend walks.
FAQ: Frequently asked questions
Can I make a boat on an air cushion myself?
Yes, it's a popular project among home-makers, but it requires a precise engineering calculation of the ratio of engine power, body weight, and cushion area, and miscalculations result in the machine either staying on the ground or becoming unmanageable.
What is the maximum speed of these boats?
Amateur models develop speeds from 40 to 80 km / h. Sports and military models can reach much higher rates, but for civilian use, high speed on the water is often unnecessarily dangerous.
Do I need to register with GIMS for SVP?
Yes, if the mass of the boat in running order exceeds 200 kg or the engine power exceeds 8 kW (about 10.8 hp), in this case, the MVP is equivalent to small vessels and requires registration and management rights of the appropriate category.
Is the SVP afraid of punctures like a PVC boat?
Less than it seems. Due to compartmentalization (if the skirt is sectional) or air inertia, a small puncture does not cause an instantaneous fall. The machine can continue to move, although efficiency will decrease. However, cuts longer than 10-15 cm are critical.