This article aims to create a guide to facilitate the choice when people are going to buy an inflatable boat. The material is based on years of experience working with the production and maintaining boats, consulting clients and boat owners.
Advantages of Purchasing an Inflatable Boat
- Can be transported wherever you need inside the car;
- Can be assembled/disassembled by one / two people in 5-20 minutes;
- Can be stored in the garage, shed, closet or balcony;
- Has a large carrying capacity;
- Has good stability (it is challenging to flip the boat whether in a standing position or on the move);
- Practically not sinkable;
- Can be seaworthy and high-speed (more on that later);
- The most affordable floating craft.
Answer these Questions when Choosing an Inflatable Boat
- What bodies of water will I operate the boat on.
- What will I use the boat for (fishing, hunting or recreation.)
- What is the minimum permanent crew expected?
- What is the maximum crew expected?
- What engine power do I want or have.
- What speed is needed.
- What weight is critical for me personally.
In 80% of cases, the more accurately you formulate your wishes, the more the chosen option will fully meet your expectations. You should know that there is no boat for all occasions.
Types of Inflatable Boats
1. Flat-bottomed Boat Without Sleigh
1. The most negligible weight.
2. The minimum dimensions of the package.
3. The lowest price.
Disadvantage – you cannot stand in the boat.
This version uses fabrics with a density of 650-750 g / m2. This density is quite enough for boats of this type. Nevertheless, it is necessary to consider that the higher the thickness of the fabric, the greater the weight of the boat and the dimensions of its packing.
2. Flat-bottomed Boat with a Slatted Bottom
Slate is an insert in the bottom made of waterproof plywood. It makes the base more rigid and allows the boat to stand. The slatted floor boat will be slightly heavier than the previous design. Although the price and time of assembly and disassembly will be comparable, this design has all the advantages of a boat without a slate. Still, it has no drawback – you can stand in it.
The slate distributes the load over a particular area of the bottom. Boats with this type of floor can be either rowing or motorboat. These boats are the most common due to the democratic price and mobility.
Disadvantages of this type of boat are:
There is no problem if you take a rowing boat, but the slate gives the bottom lateral rigidity with motorboats and practically does not add longitudinal rigidity. In this regard, the design has poor hydrodynamics. At a certain speed, the bottom enters into resonance and begins to move in a wave. The resonance disrupts the hydrodynamic flow, and the boat stops picking up speed, even if the engine power allows it.
Such a bottom is a tunnel through the raised bow, and the boat picks up the air under the base. A bubble begins to form, which pops up from behind the transom after a while. As a result, the engine picks up air. You can hear how it is rapidly gaining momentum. And then, it happens again.
A slate boat is not a speed boat. Therefore, the race for the power of the motors is inappropriate. In this case, a 2.5-5 hp motor is more efficient than an electric motor. Installing a fully rigid plywood deck or adding more slats and widening them can improve the Hydrodynamics. After that, the boat will quickly begin planning. Consequently, the speed will increase significantly, and it will be possible to move the boat around. Nevertheless, the boat’s weight, price and assembly time will be comparable to keel motorboats.
The next disadvantage is such driving characteristics as handling and seaworthiness. A feature of any flat-bottomed boat design (no matter if it is rigid or inflatable) is the presence of side drift when entering a turn. Gluing an inflatable keel underneath will improve the part of the handling. Nevertheless, don’t expect it to increase longitudinal stiffness and enhance hydrodynamics.
How a flat-bottomed boat behaves on a wave
It doesn’t cut her. The boat will ride the wave. Travelling on a wave on a flat-bottomed boat is very uncomfortable. That is by no means an option for large bodies of water.
What to look for when buying a slatted floor boat
First of all, pay attention to the distribution of slates along the bottom. It should not be too big, especially in the area near the transom intended for planning. Otherwise, an air bubble will be formed there. The closer the slates get to the transom, the better.
Due to the presence of a keel, the boat has good controllability. It also can overcome the wave (the keel partially cuts it and diverts the water to the sides). Besides, the design of boats is more rigid, and the bottom has good hydrodynamics. As a result, boats are faster and allow the installation of more powerful motors than slate boats.
3. Keelboat with Inflatable Flooring
In terms of price, they are much more expensive than rigid flooring. In terms of structural rigidity and weight, they are an intermediate option between slate boats and keelboats with tough flooring.
A unique feature of the keelboat is the inflatable flooring. As a result, the boat is 10-15 kg lighter than a boat with a hard deck and more compact in packaging. Most importantly, it can be easily assembled and even thrown into the water by one person. That is an excellent option when you need to assemble a keelboat alone.
Inflatable flooring is a unique fabric consisting of two parallel warps intertwined with threads of the same length at a minimal distance from each other. The fabric is covered with a layer of PVC (or other material) from the outside. Such flooring allows you to create sufficiently high pressure in it.
What are the disadvantages?
We noted the first – a higher price. Next, the rigidity of this structure is not ideal. The motor can be installed with more power than on a slate but less than on a boat with a hard deck. The load and weight distribution across the boat will significantly affect the performance. Often observed, albeit to a much lesser extent, is the formation of an air bubble underneath.
There are also less apparent disadvantages, such as the thickness of the flooring being greater than the thickness of the plywood flooring. That means the inside headroom will be lower, and the distance from the bench to the flooring will be less. The bottom does not have a perfectly flat surface. There is a slight hump along the longitudinal axis of the base.
It would help if you kept in mind that the flooring requires additional attention. It can simply leave you without flooring if you constantly walk on it wearing sand boots and keeping sharp objects on the surface. During harsh conditions (for example, fishing in the fall or hunting), our friends cover the flooring with a piece of carpet. It collects sand and prevents the flooring from mechanical damage.
The longer the boat’s length with inflatable flooring, the less rigidity of the structure and the more pronounced negative features. In this regard, the most appropriate size for a boat with inflatable flooring is 3.5 m.
4. A Keelboat with a Hard Deck
The flooring is most often made of waterproof plywood or aluminum plates. In addition to the deck sections, the kit includes transverse and longitudinal joining profiles.
One of the most promising boat designs
A boat of this design has the highest rigidity among collapsible boats, such as the best dynamics, speed and ability to overcome the wave. A keelboat with a hard deck allows installing powerful motors (up to 40-50 HP with a length of 4.5-4.6 m). Also, this design provides maximum comfort because you move on a rigid base.
Boats with hard flooring have the most significant weight and package dimensions. Their assembly takes up to 15-20 minutes on average. It is challenging to cope with the preparation of such a boat alone. Hard deck inflatable boat owners often buy trailers to avoid the boat assembly. An inflatable boat with rigid flooring is the most acceptable option for medium and large reservoirs and harsh operating conditions.
It is good if the flooring has a non-slip notch so pay attention to that when buying a boat. A non-slip notch increases the safety of the boat. It is necessary to pay attention to the bottom deadrise angle. The higher it is, the better seaworthiness (ability to overcome the wave) and the boat’s controllability. The bottom deadrise angle is especially important for large boats with powerful engines.
Rigid Bottom Boat
5. Inflatable Boat with a Rigid Bottom (RIB)
The RIB combines a rigid hull boat and an inflatable boat that takes advantage of both designs. This class of boats will have hydrodynamics like a conventional rigid hull. Hence, the boats have excellent running characteristics, seaworthiness and comfort. The RIB received a large carrying capacity from an inflatable boat, a large buoyancy reserve, unsinkability, and excellent stability. This combination of advantages increases the popularity of this class of boats every year.
Also, RIBs remain the leading mobile and highly seaworthy boats for many special services worldwide: border guards, coast guards, police, rescuers, and the military. The plastic bottom makes the structure rigid. It also allows more powerful motors to be installed on boats and increases comfort.
Several factors determine the comfort level.
Thus, comfort is increased due to:
- the running characteristics (the boat cuts the wave better);
- the fact that you move on a stern deck;
- the fact that the flooring does not play under your feet and the latter does not rattle on the wave;
- the fact that you can equip the boat with comfortable seats, a steering console, and additional equipment.
Moreover, the boat doesn’t need to be assembled. RIBs have less weight than plastic or duralumin boats (with the exact overall dimensions). At the same time, they have more carrying capacity. As a rule, they allow the installation of more powerful motors. And the RIB price is much more democratic.
The only thing that the RIB loses to completely rigid hulls is the size of the cockpit, which will be smaller due to the large diameter of the inflatable balloon. RIB requires a trailer for transportation and storage space compared to a collapsible inflatable boat. Launching a boat with a trailer is easier and faster. You need to remember that you need good access to the water and reasonably dense bottom soil at the descent place.
The Main Stages of the Production of Inflatable Boats
First, the fabric is cut out, and preparatory work is underway to glue the cylinders (gluing in internal partitions, valves, and individual cylinder elements). When the entire balloon is glued, it gets inflated, and further operations are performed on the inflated balloon. This is the first step in checking the tightness of the cylinder. At this production stage, it is clear whether the boat is holding pressure or not. Further, after complete assembly, the boats are put on the slop, i.e. they stand inflated for a particular time. The quality control department monitors how the boats hold pressure.
Methods of Gluing Seams
There are two of them all over the world: gluing and welding. Until now, we have to hear from buyers that those manufacturers who weld the seams talk about their superiority. If this were so, one of the methods would already prevail throughout the world. This does not happen because both methods have their pros/cons.
The development of the modern chemical industry makes it possible to create very reliable materials for gluing fabrics. If you test both seam variants on a tensile testing machine, then in both cases, the break will occur in the fabric and not at the seam. The quality of craft is determined by the culture of production and quality control methods, not by the seam formation technique chosen by the manufacturer.
Inflatable Boat Fabrics
The PVC fabric is structured as follows:
- the central layer is the base;
- external and internal are protective layers (Rubber vs PVC);
- in between the bottom and the protective coatings, there are tie layers.
The nylon fabric base is responsible for the mechanical strength of the fabric. It also keeps the shape of the boat. If the base extends enormously, it means balloons have different diameters at the seams of an inflated boat.
Protective layers are designed specifically to seal fabrics, protect against aggressive environments, and provide appearance. It is not easy to connect the base and protective layers. There is such a thing called adhesion (the tendency of dissimilar particles or surfaces to cling to one another). The higher adhesion improves the cling of layers to each other. Lower adhesion increases the likelihood of tissue delamination. The task of the bonding layers is to glue the protective layer to the base. Moreover, the fabric should not have fewer than five adhesive layers. Not to mention that the fabric may look similar in appearance, but the purpose is different.
Why you need to be afraid of awning fabrics is that awning fabric is static. There is no need for high adhesion. Such material does not provide for constant folding. Also, from a security point of view, the requirements are lower. Therefore, it is inexpensive. For boats, it is essential that the fabric does not delaminate (otherwise, it will etch itself on the material) and be sufficiently elastic (to withstand many folds and folds). Yes, this fabric structure provides you with reliability. Let’s say you cut the top protective layer to the base with a sharp object. There is nothing to worry about. The inner protective layer will ensure tightness.
The following characteristic of the fabric is density. Conventionally, this is the thickness of the fabric and its layers. The higher the density of the material, the higher its mechanical resistance. But the weight of a boat made of denser fabric will also be higher. And the price will be higher. And the size of the package will be more significant. As a rule, boats for large bodies of water, large boats and RIBs are made of dense fabrics (over 1000 g / m2). So, what they are, and what do you need to know.
This fabric is exposed to ultraviolet radiation, saltwater and corrosive environments. Rubber has weak mechanical resistance and requires meticulous care: drying, cleaning, and using talcum powder. Usually, a rubber boat is heavier than PVC. All those maintenance features make its price dubious.
2. PVC (PVC – poly-vinyl chloride)
PVC is a synthetic fabric with a strong nylon (polyamide) base. The fabric is weakly exposed to ultraviolet radiation, saltwater and corrosive environments. It has high mechanical strength. The PVC material doesn’t rot. It is easy to look after it. Most inflatable boats are made of PVC. Prices for PVC boats are very reasonable.
The PVC loses elasticity at low temperatures (below 0). True, we do not often operate boats at such temperatures.
To summarize, you need to take a boat made of PVC. Today, this is the perfect combination of price/performance.
Hypalon is a rubber-based fabric, which remains exotic in our country due to its high price. Briefly, Hypalon is more elastic than PVC and has a higher upper-temperature limit. Therefore, it is justified when operating in high or low temperatures. In our temperate climate, the difference in price from PVC will be unjustified.
Features and Technical Specifications
The most important thing is how to read the technical specifications. Think about technical specifications. The boat is 3.3 m long, with a carrying capacity of 700 kg and a passenger capacity of 4 people. It is unlikely that someone will load the boat up to 700 kg during amateur operation.
Technically four people can sit in a boat, but we wouldn’t suggest loading a boat up to the maximum. For example, if you decide to go fishing on it, we recommend not to have more than two people over 100 kg each on the boat. Let me remind you that the selection of the boat depends on the conditions it’s going to be used in.
There is never much space in boats. Ask any experienced user. The longer the length, the better the boat will hold the wave, the easier it will be to go on planning, and the more comfortable you will feel in the boat. But starting from a length of about 3.8 m, a collapsible boat becomes less rigid.
The wider the boat, the more room it is, making the boat more stable.
The Diameter of the Cylinder
The larger the cylinder diameter, the higher the boat’s buoyancy, carrying capacity, stability and the less chance of water spilling over the side. The higher the bench is placed, the larger the sailing capacity of the boat, and the less the legs will become numb. With comparable dimensions, there will be less space in the cockpit.
Boat weight is a critical parameter. If you read all of the above, you already know which parameters affect the boat’s weight. This parameter is not vital for RIBs since the boat is transported and launched using a trailer. Nevertheless, when operated by one person, it becomes an essential, practically critical parameter.
Remember that the passenger capacity is calculated considering the average weight and size of the person and the safety and certification requirements. Considering only the movement state of a boat means that the parameter will not stay the same for all specific operating conditions (e.g. fishing, hunting, towing).
Recommended and Maximum Outboard Motor Power
Always check the maximum engine power and engine weight required by the boat manufacturer. Exceeding these parameters is the basis for losing the warranty. The maximum engine power lets you squeeze all the potential out of the boat. In this case, external factors will be a minor extent. The main thing is that you do not feel discomfort from the weight of the motor.
While it is understandable about the maximum motor power, the question arises about the recommended one. The trick is quite simple – do not put the less potent motors than recommended. Always rely on the worst-case scenario on the water, such as you have a maximum load, a big wave, or a strong headwind. It may turn out that you will go where you are forced and not where you need to. Pay attention to matching boat transom height and motor leg length.
That’s all you need to know as a first approximation when buying a boat. We are sure this information will help you in the throes of choice. All that remains is to wish you to make an informed choice and start enjoying it.