Redeemers on the boat: purpose, types and how they change the behavior of the boat on the water

If you've ever looked at the bottom of a boat -- especially a high-speed or professional model -- you've probably noticed longitudinal protrusions going from nose to stern. rentansThe redundancy often seems like a bit of a complexity to beginners, but it actually does a number of critical functions, from speeding up to handling in challenging environments.

Many boat owners mistakenly believe that reds are only for racing models or large boats, but even on small PVC boats or aluminum "communities" smartly designed reds can reduce fuel consumption, reduce splashes on board and make the trip more comfortable. In this article, we will discuss how the redans work, what are their types, and why some manufacturers abandon them in favor of a smooth bottom.

Spoiler: If you're planning to tune your boat or you're choosing a new model, understanding the principles of redans can help you avoid common mistakes. mounting It can be a speed gain, it can only worsen the stability of the wave, or vice versa, the right configuration will save up to 15% of fuel on long transitions.

What are the Revenants and How They Are Made

term "Redan." (from French) redan And what we call "barrier" in shipbuilding is the longitudinal ledge on the bottom, which creates additional points of support when you're moving, and unlike the keel, which is centered and is responsible for stability, the reds are symmetrically positioned on the sides and they do a different job. flowReduce resistance and improve glossing.

Structurally, the redan is a flat or slightly rounded strip, raised above the main bottom by 1-5 cm (depending on the type of boat).

• 🛥️ Single redan - occurs on small boats and boats, provides a basic improvement in planing.
• 🏄 Double reeds - Classic scheme for most motor boats, optimal for speeds of 30-60 km / h.
• 🚤 Multi-resided systems (3-5 protrusions) – used on racing boats and large vessels for maximum stability at high speeds.

The material of the lease depends on the type of boat:

• 🧵 Nana PVC boats Redans are formed due to welded seams or glued strips of reinforced PVC.
• 🔧 Nana aluminum-boat - these are stamped or welded elements from the same alloy as the body.
• 🧪 Nana fiberglass and composite The boats are cast together with the hull as a whole.

It's important to understand that redeemed is not a universal solution, and its effectiveness depends on a combination of three factors:

1. Engine power (redans are useless without sufficient thrust).
2. Boat hull shapes (on round-bottomed models they work differently than on flat-bottomed ones).
3. Conditions of operation (in calm water or with heavy chop).

The main functions of the redans: why they are needed

The main task of the redans is Optimize the interaction of the body with water So let's look at how they do it.

1. Reduced water resistance

When a boat moves, the water under the bottom creates lift, but it also slows the boat down. divide the flow into several narrow channelsThis reduces turbulence and makes it easier for the boat to go out onto the glider, and tests show that properly designed redans reduce drag by 10 to 25 percent compared to smooth bottoms.

2. Improved planing

Without redanes, the boat needs more power to move from sailing to planing mode (where the hull slides through the water rather than cutting it), and the redans create additional footholds, allowing:

• 🔹 Quicker to go to the plane at lower engine speeds.
• 🔹 Maintain planing at lower speeds (fuel economy).
• 🔹 Reduce the "subsidence" of the feed during acceleration.

3. Increased stability on the wave

On flat water, the reds are almost invisible, but on excitement they play a key role:

• 🌊 Prevent side slip ("skid") during corners.
• 🌊 Reduce the likelihood of overturning with sharp maneuvers.
• 🌊 Reduce vertical swing (the boat is less "jumping" on the waves).

Reduced spraying and splashing of sides

At high speed, water sloughing off the bottom creates a cloud of spray that not only interferes with view, but also increases air resistance, and Redans direct the flow of water downwards, reducing the spraying of the sides by 30 to 50 percent.

5. Fuel economy

By reducing drag and plane more efficiently, a boat with redans consumes 5 to 15 percent less fuel at the same speeds, especially on long crossings.

The myth of "eternal" redancing

Why do some boats wear out faster than the hull?

The wear rate of the redan depends on the material. For example, on aluminum boats, welded redans can be washed off from sand and gravel in shallow water, and on PVC boats, they can peel off if they are not stored properly. Manufacturers often reinforce the redan with additional stainless steel or composites linings, but even these require periodic inspection.

Types of Redan: which to choose for your boat

Not all the redeemeds are the same. They're shaped, numbered, and arranged for specific tasks. Let's look at the basic types.

Type of redan	Design features	Advantages	Deficiencies	Which boats are suitable for
Direct reeds	Parallel projections from nose to transmunus	Ease of manufacture, low resistance	Weak stability at corners	Small PVC boats, fishing "communities"
Stepped redoubts	Bedges of different heights (usually 2-3 levels)	Excellent planing, high speed	Difficult to repair, sensitive to overload	Speedboats, sports boats
V-shaped renditions	The projections converge to the stern at an angle.	Good handling on the wave	Greater resistance at low speeds	Sea boats, boats for open water
Hydrodynamic redanes	Combined form with variable profile	Maximum efficiency in all modes	Roads in production require accurate calculations	Premium boats, professional vessels

Which type to choose? Here are some brief recommendations:

• 🎣 For topping up (Lakes, rivers) will fit straight or slightly curved reds.
• ⚡ For speed-walk or towing skiers need stepped or hydrodynamic.
• 🌊 For sea-cruising with waves of 1 m + optimal V-shaped or combined.

Interesting fact: on some modern boats (for example, the Brig Eagle 6 or Yamaha 242 Limited Suse symmetrical - when the ledges on the right and left side have different shapes, which allows you to compensate for the effect of rotation of the propeller on handling.

Redans vs. Smooth Underbody: Which Is Better?

The debate over whether to rent on a boat has been going on for decades, and let's compare the two in key terms:

1. Speed and acceleration

Boats with reds go out faster on the plane and support it at lower revs. Aluminum boat Kazanka-5M With redans, it accelerates to 40 km / h with a 15 hp engine, while the same model with a smooth bottom barely reaches 35 km / h.

2. Steadiness on the wave

On flat water, the difference is almost imperceptible, but on excitement, the boat with the redans behaves more predictable:

• 🔵 Less tilts in corners.
• 🔵 Less often, he's nose-in-the-wave.
• 🔵 It quickly restores the course after a shock to the wave.

3. Fuel consumption

According to the journal's tests Boats and Yachts.A boat with redans consumes 8-12% less fuel at cruising speed (for example, 30-40 km / h), but at low speeds (up to 20 km / h), the difference is minimal.

Repairability

A smooth bottom is easier to repair: there are no protrusions that can be damaged or that interfere with welding, and Redans require care when repairing, especially if they are welded or pasted.

5. Price.

Boats with redanes are typically 10 to 30 percent more expensive because of the complexity of production. PVC boat "Fregat-360" With reds costs ~ 120 000 rubles, and the same model with a smooth bottom - ~ 95,000 rubles.

When is a smooth underside preferable?

• 🚣 For boats with engines up to 5 hp (redan will not give a noticeable effect).
• 🏞️ For operation in shallow water with a rocky bottom (redans can cling).
• 💰 If the budget is limited and the speed is not critical.

How Reedans Affect Boat Controllability

Experienced water-engineers know that a boat with a redana behaves differently on the water than on a smooth bottom.

1. Turns

Redans improve traction, so the boat is better "holds the track" and less slips sideways. slip-roll - especially on boats with high reds, to avoid tipping over, it is recommended:

• 🔄 Slow down before turning.
• 🔄 Smoothly turn the steering wheel, avoiding jerks.
• 🔄 Distribute the weight of the crew closer to the center of the boat.

Drift in side wind

In open water, the wind can blow the boat aside, and Redans can partially offset this effect, but not completely. trim (Stop and down) and spread the load evenly.

Reaction to gas

Boats with redanes respond faster to gas, but they also squat more sternly when they accelerate sharply, to avoid this:

• ⚡ Accelerate smoothly, especially with full load.
• ⚡ Use the trim for the optimal angle of attack.

4. Braking

When you dump the redane boat, it keeps inertia longer because it's better at sliding, which is a plus for speed crossings, but a minus if you need an emergency stop.

Frequent errors in the selection and operation of redans

Even experienced boat owners sometimes make mistakes with redans.

Engine power mismatch

Installation of high redan on a boat with an engine up to 10 hp is not only useless, but also dangerous.: the boat will be worse at steering and may tip over when turning.

• 🔋 Up to 10 hp - 1-2 small redan height of 1-1.5 cm is enough.
• 🔋 10–30 hp - optimally 2-3 redana height of 2-3 cm.
• 🔋 From 30 hp - you can use stepped or V-shaped redans.

2. Overloading of the boat

Reds are designed to carry a certain load. If you exceed the permissible weight, the boat will "burrow" nose, and the reds will work like brakes. Always check the data-sheet figures for load capacity!

3. Wrong trim

Many people forget that the reds are only effective at the right angle of attack, if the engine is picked up too high.positive, the boat will start to bounce on the waves.negative) will increase resistance.

4. Ignoring the state of redanas

Damaged or contaminated redans lose their properties and inspect them regularly for:

• 🔍 Cracks (on PVC boats).
• 🔍 dents or burrs (on aluminum boats).
• 🔍 (If the stains are stained)

⚠️ Attention: If the aluminium boat welds the welds with spot welding, check the seams for corrosion. In salt water, they can break down in 2-3 seasons!

5. Homemade reeds

Some owners try to make reds themselves by gluing PVC strips or welding metal plates, which is dangerous for two reasons:

1. The boat's balancing is broken.
2. Homemade reds can fall off on the go.

If you want to modify the boat, contact the professionals or buy a model with factory redanes.

How to care for rents: maintenance tips

Reds, like any part of the boat, require maintenance.

1. Purge.

After each launching:

• 🧽 Wash the redans with fresh water (especially after salty water bodies).
• 🧽 Remove the adhesive algae or sand with a plastic scraper (not metal!).
• 🧽 For persistent contaminants, use special cleaners (for example, Star brite Hull Cleaner).

Protection against damage

During transport or storage:

• 🚛 Cover the boat with a cover to avoid scratches.
• 🚛 Do not put the boat on the redan (use the stands under the hull).
• 🚛 Avoid dragging over rocks or sand.

3. Repairs.

In case of damage:

• 🔧 Nana PVC boats Small cuts on the reds can be sealed PVC glue (for example, Bostik 2120) with a reinforcement patch.
• 🔧 Nana aluminum-boat The dents are leveled with a richt, and the cracks are brewed with argon welding.
• 🔧 Nana fiberglass The chips are slapped and covered with gelcoat.

⚠️ Attention: If the redane has broken off or deformed by more than 30%, do not try to repair it yourself - contact the service.

4 Storage

In winter or in the long term, it is simple:

• ❄️ Keep the boat in a dry, ventilated room.
• ❄️ Inflatable boats with redanes are better stored in a semi-inflated state to avoid deformation.
• ❄️ Periodically inspect the reds for mold or corrosion.

5. Modifications

If you want to improve the boat’s performance, consider:

• 🔧 Installation rent-out (for example, Redan Booster for PVC boats.
• 🔧 Sticker hydrodynamic strips (for example, Hydroturbo).
• 🔧 Optimization of the engine trim for existing drives.

FAQ: Answers to Frequent Questions about Rentals

Can I install the redeemed on the boat if they were not from the factory?

Technically, yes, but it requires a professional approach. PVC boats redanes can be glued using heat welding or special glue (for example, Cléopâtre 5000On aluminum-boat They're welded or riveted, but self-assembly can lead to:

• Balancing violation.
• Deteriorating handling.
• Loss of warranty (if the boat is new)

It is better to buy a boat with factory redanas or contact specialized workshops.

How do redans affect the maximum speed of the boat?

All other things being equal, the boat with the redans accelerates faster and reaches a higher maximum speed.

• The winger 420 boat. with an engine of 20 hp and a smooth bottom accelerates to 45 km / h.
• The same model with redans - up to 50-52 km / h.

However, the speed increase depends on:

• Redan forms (stepped ones give a greater effect than straight ones).
• Engine power (on low-power engines the difference is minimal).
• Boat loading (when overloading the reds lose efficiency).

Is it true that the redans increase fuel consumption at low speeds?

Yes, it is. At speeds up to 20 km/h (swimming rather than planing), the redans create additional drag, which can increase fuel consumption by 5 to 10 percent. fuel-efficient It's because of better gleaming.

The bottom line is that if you walk at low speeds a lot (like trolling a fish), the reds don't really pay off. If you prefer high speed, they pay off.

Can I use a boat with redans in shallow water?

You can, but with caution.

• 🪨 Redans can cling to stones or snags, especially if they are tall (more than 3 cm).
• 🪨 On the sandy bottom between the redans accumulates sand, which is difficult to wash.
• 🪨 When dragging along the pebble bank, reds wear out faster.

Tips for shallow water:

• Choose boats with low-rounded redans (for example, Bark 320).
• Install. removable lining We're going to re-rent out of solid plastic.
• Avoid the harsh maneuvers of the shore.

Which boats do not need redundancies?

Redeemeds are useless or even harmful in the following cases:

• 🚣 Boats with engines up to 5 hp (lack of power for planing).
• 🚣 Rowing boats or boats with oars (redans will only increase resistance).
• 🚣 Boats for rafting on rivers with rapids (redans can catch obstacles).
• 🚣 Inflatable boats with hinged transom, if they are used only for fishing in calm water.

Also, redeemed are not needed on boats with hydrodynamic (for example, RIB or variable-kilometer) where their function is performed by the shape of the shell itself.