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Hobbyking bat 1 rc land yacht: all you need is wind and a sail.

RC Boat Staff August 17, 2016 Reviews 738 Views

IN THE WIND

After wrapping my head around how the sail system works, it was time to head outside and give this wind-powered 3-wheeler some stick time. I gathered up the BAT, the transmitter and the ambitious E-Man and trekked out to the parking structure outside our building. It was a beautiful day, however there was very little wind; the one thing we needed. We gave it our best but without that wind the BAT 1 barely moved. Back to the office we went.

Let me tell you that having the BAT in my office on the bench staring me in the face was like getting a new bike for Christmas only to find out it’s raining outside. It was four days before Mother Nature finally decided to cast some wind my way, so it was back outside to give the BAT another try.  AUTHOR’S OPINION

Anything RC is fun for us and when the BAT 1 rolled into the office, we were pretty excited to try it since it was something a little different. Once you get it going (that is, once there’s wind), it’s actually really fun to drive. The controls are similar to a regular RC car so if you have any experience driving, you’ll pick this up in no time.

• Electronics already installed
• Easy assembly with very few parts
• Low-drag foam tires
• Only requires four “AA” batteries
• Requires wind or it won’t move

Transmitter on; switch on. Steering working; check. Boom swinging; check. After my ‘all systems go’ check, I set the BAT down and immediately it started speeding away as the wind caught the open sail. As I approached the end of the parking area, I applied brakes on the throttle to cinch the sail in but found that the BAT doesn’t actually have brakes! Cinching in the sail only limits the amount of air that it gathers; slowing down is simply a matter of it losing speed! Panicking a bit, I cranked the wheel and the BAT aggressively whipped around and almost immediately the sail swung around to the other side. Ah, now I’m getting the hang of it. No matter which way the BAT is pointed, the sail will swing to the ‘wind’ side as long as you have the throttle open.

I drove the BAT around for what seemed like an eternity before Edwin graciously noted that he’d been done with pictures for about 20 minutes! Yes, the run-time on this thing is unreal; as long as your “AA”’s are fresh and there is wind, you could go all day!

FEATURE BREAKDOWN

• Since the BAT is powered by wind, it only needs the giant sail for movement. The main sheet line extends out of the hull and is attached to the sail at one end and a second servo on the other. Connecting the sheet line is a little tricky … it took me a few tries to figure out exactly how it works. The throttle on the transmitter actuates the sail, but here’s the trick: when you pull the throttle on the transmitter (similar to accelerating in a normal RC car), it provides slack in the main sheet line and allows the sail to swing, catching air and moving the BAT forward. When you push forward on the throttle (similar to braking on a normal RC car), you are cinching in the main sheet line, or preventing it from swinging. This keeps the sail inline with the BAT and limits the amount of air it can catch, effectively slowing it down. Trust me, it’s weird at first but you’ll get the hang of it.

NEEDED TO COMPLETE

• AA batteries

DIMENSIONS LENGTH: 28.7-inch (730mm) WIDTH: 19.7-inch (500mm) HEIGHT: 39.4-inch (1000mm) SAIL AREA: 0.15m² WEIGHT: 692g

BODY, WHEELS AND TIRES BODY: Pre-molded 2-piece hull WHEELS: Plastic with bearings TIRES: Foam donuts

SUSPENSION TYPE: None SHOCK POSITIONS: No shocks CAMBER: Fixed ROLL: Fixed WHEELBASE: Fixed RIDE HEIGHT: Fixed

STEERING TYPE: Direct TOE: None CHASSIS TYPE: 2-piece hull MATERIAL: Plastic THICKNESS: N/A

DRIVETRAIN TYPE: Wind power! TRANSMISSION: None DIFFERENTIAL: None CLUTCH TYPE: None GEAR RATIO: None BEARINGS: Full shielded

THE LAST WORD

HobbyKing , hobbyking.com

Design Tips

In the process of designing my own model landsailers over the last few years I've learned a lot and developed a few calculations that have proven useful. Below you will find a series of mini-articles on model landsailer design as well as a few spreadsheet design tools for making simple calculations. In the interest of promoting this hobby I'm sharing these tools and advice with you.

I'm always trying to improve and add to the information here so if you have any questions about the information below or something that's not here please email me and I'll be happy to discuss it and maybe the answer will end up on this page

OVERVIEW OF DESIGN ISSUES

LANDYACHT VELOCITY PREDICTION PROGRAM

Wing Mast Experiments

• Sail Design Tool

Sail Scaling Formula

Why landsailers don't have jibs, ls mast system.

• Wheel Selection
• Bearing Selection
• Optimum Center of Mass (ballast location)
• Expected Loads
• Beam Bending Analysis Tool
• Speedometer Setup

Generating down force with rear beam

• Center of Lateral Resistance

Optimizing Length/Width Ratio for Maximum Righting Moment

General design issues.

This article is an attempt to describe the big picture of model design. In general there are two primary measurements of model performance; acceleration and top speed and the following description explains which model variables affect these two performance characteristics.

Acceleration

Acceleration is important when racing around a course when you need to change directions and get the most speed out of each gust. The very simple relationship that determines acceleration is Force = mass x acceleration. It says that a body experiencing a force will have an acceleration that is equal to the net applied force divided by the body's mass. This means that one way to increase model acceleration is to make it as light as possible. Alternatively, you can increase the net force by increasing the thrust generated by the sail or by decreasing the model drag. Increasing the sail thrust can be done by improving the sail lift to drag ratio (like using a wing mast) or by increasing the sail area. Since you need more weight to carry more sail area you can see that there must be some balance between model weight and sail area. The other way to increase net force is to reduce model drag. In practice this in not very effective because drag force is proportional to velocity squared. When accelerating from low speed these forces are small compared to the sail thrust and so body drag is not very important to acceleration. In fact, if the model is moving downwind and has not yet reached wind speed a larger body drag force may actually increase acceleration.

The conclusion is that model mass, sail lift/drag ratio and sail area are the primary variables that influence model acceleration. Acceleration can be improved only by increasing the sail lift/drag ratio and correctly balancing model weight with sail area.

Top speed is important when racing in a straight line on a long leg of a course. Calculating maximum model velocity is more complicated than acceleration but we can still determine the primary factors that influence it. Maximum model velocity occurs when the thrust force generated by the sail is equal to the combined drag force of the sail, body and wheels. Model weight has no direct correlation to maximum velocity. Instead we must consider the lift/drag ratio of the sail, the sail area, the aerodynamic drag of the model body and the drag in the wheels. Maximum velocity can be increased by improving the sail lift/drag ratio, increasing the sail area and decreasing the model drag. Because sail area must still be balanced with model mass, one way to increase top speed is to carry a large sail and make the model very heavy but this will adversely affect acceleration and maneuverability.

The best way to increase top speed, besides improving the sail performance, is to reduce drag by using low friction ball bearings in the wheels and making the body slim and streamlined to reduce friction.

Conclusions

Increasing the lift/drag ratio of the sail increases model acceleration and top speed while sail area and model mass must be properly balanced for optimum performance. In addition, reducing the model drag from the body and wheels will increase model top speed but has little effect on acceleration.

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Program Description

The program described here is a Matlab script that was written to predict the speed and loading on a landyacht based on the yacht configuration, the wind conditions and the vehicle heading. To run the file you need a version of Matlab or you will need to convert the algorithm to some other language but you can at least view the file with WordPad. The algorithm doesn't make any assumptions about the size of the landyacht and so it is valid for models and full size landyachts alike. I don't have much data to compare the results to but it seems to at least be in the right ballpark for predicting yacht speeds.

The program works by guessing at and then adjusting the vehicle velocity until the net thrust is close to zero (steady state operation, i.e. top speed) for all possible headings (0-180 degrees) and sail/wing trim angles (0-60 degrees). It then stores the maximum velocity for each heading that also satisfies the criteria that the vehicle can't flip over or slide sideways. It also stores the maximum possible velocity when slipping and flipping are ignored so that you can see how close your design is to achieving it's maximum possible speed. This information is then plotted in a polar plot like the one below:

The red line represents the maximum speed when flipping and slipping are ignored. The blue line is the maximum vehicle velocity when flipping and slipping are taken into consideration. In this case, the yacht could achieve greater speeds if it were made heavier or if it made use of down force. One useful aspect of this program is that it can be used to predict how much weight is required to prevent slipping and flipping for given wind conditions and yacht configurations. Based on this information the program can also estimate the loads the vehicle will experience for any wind speed, yacht speed, rig trim and heading.

To use the program to simulate your own yacht you just need to change the yacht parameters to match your own design and run the script for the wind speed you're interested in. If you do use this program in the design of a full sized landyacht or a model, please send feedback to [email protected] along with any real data you have to compare to predictions. If you do not have access to Matlab, I will be happy to run the script for you if you provide me with the necessary yacht parameters.

To download the script right click the link below and "save as"

Matlab Velocity Prediction Script

John Horstkamp, a student at George Mason University, has translated this script to a program that can be run on any Windows machine. To download the zipped file, click here .

RIG DESIGN TOPICS

I have constructed several wing masts for the LS-3 and LS-4 platforms. The wing is similar in construction to a model plane wing with slight modifications to the trailing edge allowing for a sail slot. The balsa and basswood wing skeleton is shown below.

The wooden skeleton is then covered with monokote heat shrink aircraft covering to form the surface. This construction is very light, extremely strong and relatively inexpensive.

In light wind conditions (less than 15 mph) a small sail is attached using the LS-3 quick change groove system. In heavier wind conditions the sail is removed and the wing alone can be used to power the model. Though this configuration is faster than the storm sail rig it is much more sensitive and therefore more difficult to sail.

The resulting rig noticeably outperforms the standard rig reaching speeds 30-40% greater than the rectangular mast with mylar sail. To see the detailed data see the speedometer section.

The most interesting observation I have made so far is that wing thickness and tapering have no noticeable effect on wing performance. The only important variable seems to be wing area which must be balanced with the model righting moment. With this in mind, the LS-3 wing mast has been designed to provide sufficient power by itself in a 20 mph breeze. In lighter conditions the addition of the mylar sail increases the rig power so that the wing rig can outperform the stock mast and sail in all wind conditions. The LS-3 in now available with a wing mast option for a small increase in cost, and the wing mast is standard on the LS-4 .

Sail design tool

This spreadsheet is meant to make sail design a little faster. It takes a few inputs, such as luff length and rake angle, and calculates sail area, the location of the center of effort and draws a simple picture of what the sail will look like. I use it to quickly run through a few different sail plans before I start cutting. Because the materials are relatively cheap, it's a good idea to build a few sails for different wind conditions like windsurfers do.

This article develops an equation for determining an appropriate scaling factor for making a sail bigger or smaller than an existing sail that is already known to work well in a particular range of wind conditions. This is intended for making multiple sails for use on the same yacht. It may not be valid for estimating appropriate sail scaling between different yachts. The equations presented assume a triangular sail shape that is scaled in such a way that the aspect ratio is maintained from one sail to the next, though this same approach could be used to derive the scaling laws for differently shaped sails as well.

Lets say you already have a sail that works great on your model in 10 mph winds and you want to make a similarly shaped smaller sail for 20 mph winds (Of course, wind is variable so when we talk about 10 or 20 mph winds, what is meant is wind conditions with an average speed near that level). To accomplish this objective, you will need to reduce the size of the sail enough that the new sail generates the same amount of heeling moment in 20 mph winds that the old one did in 10 mph winds. But how much smaller should you make it? Changing the size of the sail makes the yacht better suited for more or less wind for two reasons. First, the sail size affects the sail area, which governs the magnitude of the forces generated by the sail. Second, the sail size also affects the location of the sail’s center of effort, which governs the effect that the sail force will have on the yacht. Because the center of effort changes, the mast step will also have to be shifted either forward or backwards to maintain proper helm balance. Another result of this effect is that since a smaller sail will have a lower center of effort, it can generate higher forces before exceeding the yachts maximum stable heeling moment. This means that more thrust can be generated before the yacht will tip, which is one of the reasons that yacht speed increases as wind speed increases.

Scaling Equation

S - sail scaling factor you want to compute (scaling of each sail dimension)

R - ratio of new design wind speed to old design wind speed (in this example R = 20mph/10mph = 2)

The following is a scaling equation for a triangular sail shape (click here for derivation):

S = R^(-2/3)

When plotted this function looks like this:

There is also an excel worksheet that will perform this calculation for you: click here.

An example of how to use this formula will now be presented. Although in this example, the formula is used to scale down, it can also be used to scale up. Assume you already have a sail that works well in 10 mph winds with the following dimensions:

Original sail dimensions:

Foot (triangle base “b”) = 10 in

Leach (triangle height “h”) = 50 in

Area “A” = 250 sq. in

Now you decide that you would like to make a new sail that will generate a similar heeling moment in 20 mph winds. The variable “R” is 20 mph/10 mph so R = 2. Using the above equations or plots, when R = 2, S = 0.63. Now we multiply the original sail dimensions by “S” to get the new dimensions:

New scaled sail dimensions:

Foot (triangle base “b”) = 10 in x 0.63 = 6.3 in

Leach (triangle height “h”) = 50 in x 0.63 = 31.5 in

Area “A” = 99 sq. in

While this method does not take into account differences in mast bend, Reynolds number and other secondary effects, it should provide a very good estimate for scaling up or down from an existing sail configuration. Once the mast step is repositioned properly, this new sail should behave similarly in 20 mph as the original did in 10 mph winds.

It seems that every soft water sailor who contacts me asks why my models don't have jibs.

To understand the difference between soft water sailing and landsailing you must think about working in an entirely new realm of speed where the effect of apparent wind actually exceeds the true wind. Because the resistance to forward motion is so small on a landsailer, it will quickly reach wind speed at almost any point of sail other than head to wind. At that point the vehicle speed will increase further based on the combined effect of the true wind added to the apparent wind. This makes it possible to reach speeds in excess of 3 times wind speed! This means that once under way, a landsailer (even a model) is essentially going upwind no matter what it's angle to the true wind.

At these high speeds and low angles of attack a single sail rig is vastly superior to a multi sail rig because it can generate a higher lift to drag ratio than multiple sails. This is why you will never see a modern land yacht with a jib (see http//www.nalsa.org/ ) or a bi-plane for that matter. The same reasoning applies for models. When you're sailing a monohull these effects are not apparent because of the limits of hull speed, but you don't need to be going 60 mph to see this effect. If you've ever sailed on a modern beach catamaran you know that in an upwind leg a jib is often a hindrance which is why the fastest cats use a single, wing like main sail for upwind work and a retractable reaching sail for downwind work.

I hope this explanation satisfies anyone's urges to try a jib on their land yacht. While I enjoy and encourage experimenting with new rigs and configurations to enhance model performance this is one test that has been done many times before. Why not try a wing instead!

Since I've heard quite a few questions about my spring loaded side stays I've provided a short description below.

As it turns out, I've found that model performance is also very dependent on rig tension. Specifically, the model is much faster when the sail leans to leeward. This behavior is much harder to explain, but I'll try.

These figures try to show the difference in the vectors of the air flow over the sail for a vertical and tilted configuration.

With the sail vertical, the air is forced to flow approximately parallel to the foot of the sail so that the resultant forces on the model are to leeward (which causes sliding) and forward (to cause forward acceleration).

When the sail is leaning to leeward, the air flows upwards and to leeward (parallel to the mast). That results in two forces down and to windward that weren't present when the mast was vertical. This additional force to windward (which counteracts the leeward force and improves balance) may explain the better performance of the tilted rig.

PLATFORM DESIGN TOPICS

Wheel selection (urethane inline skate wheels vs. foam RC plane wheels)

I have also tried both types of wheels and there are three main reasons I feel urethane wheels are better than foam plane wheels for model landsailers.

And now thanks to the increased popularity of foot scooters urethane wheels with diameters of 125 mm and even larger are now available.

If you are planning on purchasing inline skate wheels I recommend the closeout deals at www.skatepro.com

Bearing selection

There are many grades of bearings available for roller blade wheels and I have tried several to determine the impact of bearing quality on model speed. Delrin bearings range in quality from ABEC 1 to ABEC 3, 5 and 7 with ABEC 1 being the slowest and cheapest (about $1 each) and 7 the fastest and most expensive (about $2.50 each). There are also ceramic bearings available that are even faster and more expensive ($5 or more each).

When used on inline skates or skate boards you can notice great differences in bearing performance because each set of bearings is supporting 20-40 pounds. On a model landsailer each set of bearings supports about 1-2 pounds. This small load makes the advantages of "better" bearings much smaller.

To test the effects of bearing quality on model speed two identical LS-3 's were raced. One was fitted with ABEC 1's and the other with ABEC 7's. The result was that the LS-3 equipped with ABEC 7's had a slight advantage in wind conditions from 5-8 mph though it was barely noticeable. In winds in excess of about 8 mph no difference could be noticed.

These results lead to the conclusion that high quality bearings may be slightly advantageous for racing but do not have as much effect on speed as other features such as beam, mast and sail configuration.

Optimum Center of Mass

This section describes the best way to position weight on your model in order to counteract the force of the wind on the sail. This approach does not take into account the effect of weight distribution on model balance and vibration which should also be considered.

On a landsailer, as with any wind powered vehicle, it is beneficial to minimize overall weight to increase acceleration. Of course, some weight is required to counteract the force of the wind that tries to flip the vehicle over. How this weight is distributed determines how much righting moment (the thing that keeps you from flipping) you have per unit mass. The goal is to maximize the righting moment per unit mass so that you get the most benefit from the weight you carry. In the LS designs overall weight is minimized first and then the majority of the model weight is concentrated in the area that yields the most righting moment.

There are two methods for determining the optimum weight distribution and both lead to the same conclusion. Both methods are described below.

The results show that the best place to put the majority of the model weight is a far to the stern as possible. Furthermore, whether you concentrate the model weight at the ends of the rear beam or at the center, there should be little difference as long as the weight is balanced side to side and is far rear as possible.

Energy-Work approach

One way to approach this problem is to say that the rig must do some work on the mass of the vehicle to lift the windward wheel. If the goal is to prevent this from happening, then lifting the windward wheel a given amount should require as much work as possible. Work (or energy) is equal to force times distance. In this case, the force is the weight of the vehicle and the distance is the height that weight is raised off the ground.

To maximize the energy required to lift the wheel for a given model weight all the weight should be put where it will move the most as the wheel comes off the ground. Based on the geometry of a 3 wheeled landsailer, this distance is largest at the rear of the model near the windward wheel. Since the weight must also be symmetrically distributed for vehicle balance we can consider two cases:

If all the weight (let's say 2 pounds) is at the center of the rear beam then the work done is 5" x 2 pounds = 10 inch-pounds total.

If there are two equal weights (1 pound each) located at each end of the rear beam then the total work done is 10" x 1 pound = 10 inch-pounds total. The other pound of weight doesn't contribute because it doesn't move as the vehicle tilts. The result will be the same if the 1 pound weights are located any distance from the center as long as they are symmetric.

So as long as the weight is far rear it doesn't make any difference how you distribute it along the rear beam as long as it's symmetric.

Moment approach

We can also model the sail as exerting a moment on the model that must be counteracted to keep the model from flipping (or forcing you to let out the sail). In this case we want to maximize the moment exerted by the model weight. Since moment is distance times force you want your weight in a place where it is far from the point of rotation (the leeward rear wheel).

For example, say your beam is 30" long. If you put 1 pound of ballast at each end of the beam then as the windward wheel lifts off the ground the weight at the leeward end does nothing to counteract the sail force because it's not moving. The weight at the windward end it being lifted and is 30" from the rotation point so it exerts a moment of 30 inch-pounds (1 pound x 30") keeping you from flipping.

Now consider if instead of 1 pound at each end, you put 2 pounds in the center of the beam. As the windward wheel lifts off the ground all 2 pounds will move but now the moment arm is only 15" long and so the total moment is still 30 inch-pounds (2 pounds x 15").

So once again, as long as the weight is far rear it doesn't make any difference how you distribute it along the rear beam as long as it's symmetric.

Expected loads

By analyzing the failure mode of an early model, I was able to estimate the maximum load you can expect the main beam will have to support which can then be used to get an idea of how strong you need to make it.

In this case, a composite balsa/basswood I-beam fractured from the force of the sail pushing down on it.

The wind was blowing approximately 20 mph when this beam failed just forward of the mast step. Based on the material properties and the loading geometry, I found that the force exerted on the beam by the sail must have been at least 25 lbs. The area of the sail being used was 250 in 2 . So assuming this force increases linearly with sail area (which is probably a good approximation) this should give you a rough idea of how much load your model must support for a given sail area in 20 mph of wind.

Bottom line: To get a rough idea of how much load your beam will see in a 20 mph breeze, take your sail area in square inches and divide it by 10 to find the expected load in pounds.

Beam bending

This spreadsheet is an aid in designing beams for the main spar, rear beam and mast cross sections. It helps calculate the bending of a simple wooden beam for a given loading situation and could be modified to work for more complex structures and different materials.

Speedometer Experiments

I've been working on a system to more accurately measure model speed. To refine the measurement, I've purchased a bicycle cyclometer and fastened it to one of the rear wheels as seen in the accompanying pictures.

This cyclometer is an avocet cyclometer model 15 which was chosen for its capability to be programmed for wheel circumferences as small as 100 mm eliminating the need to convert the display's velocity read out. This model also has a maximum speed function which is required on a model if you wish to see how fast you were going.

The system is relatively cheap and simple to put together but the initial results were disappointing. The speedometer hit a limit at 11.2 mph, and was incapable of measuring any higher speeds on the 80mm wheels. Since the recommended sensor position is 3" from the axle with a top speed measurement of 75 mph, and on the model it was mounted approximately 1" from the axle, the maximum speed expected is about 25 mph. This suggested that there was a mounting/alignment problem that needed to be corrected before an accurate velocity measurement could be made.

The magnet was remounted on a larger 110mm urethane wheel and the maximum speed increased to 15 mph but did not work at higher speeds as you can see in the following plot.

Preliminary results are shown here for the LS-3 with the standard sail (pink) and with the developmental wing mast (blue) though no data has been taken yet in winds over about 9 mph. The horizontal axis represents wind speed and the vertical axis is model speed. As you can see the LS-3 exceeds wind speed by 50-100% and may even do better in higher winds. The velocity curves fall off at higher speeds because the speedometer is currently not capable of measuring speeds greater than 15 mph.

Traditionally in any sailing vehicle the only force that is used to counteract the sail and keep the vehicle from flipping over is weight. An alternative is to generate an aerodynamic force (down force) to counteract the sail. In most sailing vehicles the air velocity simply isn't large enough to easily generate significant amounts of force but on a model landsailer apparent wind velocities can easily reach twice wind speed. This makes it possible to use the model's rear beam to generate an appreciable down force (about 1/4 to 1/3 of the model weight). This can be accomplished by making the rear beam in the shape of an asymmetric airfoil. The drawback is that an asymmetric airfoil creates more drag than an equally sized symmetric foil.

To determine if the benefits of this design outweigh the extra drag the performance of the LS-4 prototype design was simulated for a symmetric rear beam and a down force generating asymmetric beam. The polar plot of vehicle velocity vs. wind angle is shown below for both designs in a 20 mph breeze. The result is that the asymmetric design, shown in blue, is slightly faster (about 1 mph) than the symmetric design for most points of sail. Both designs are predicted to reach speeds of 28 mph using the wing mast alone in the 20 mph breeze.

During some initial tests on the prototype LS-4 this technique seems to have some large benefits. The result is a much more stable model with no noticeable affect on top speed. This is possible because the slight increased in air drag is balanced out by the fact that the model can safely carry more sail area and use more of the existing power to generate more thrust without flipping.

Locating the Center of Lateral Resistance

Lateral resistance is the force or forces that oppose sideways motion in a yacht (land or otherwise).  It is important to know where the center of lateral resistance is so that you can position the sail's center of effort nearby to control the helm (the tendency of the yacht to turn up into the wind or down away from the wind when you stop steering).  In the case of a boat, the lateral resistance is provided by the hull and the foils (i.e. rudder and center board).  On a landyacht, the friction between the wheels and the ground provides the lateral resistance.  The center of lateral resistance (CLR) is the point along the length of yacht where, if you push it sideways, it will slide sideways without rotating.  You can also think of this point as the place where all the lateral resistance force would be acting if it was only a single force, rather than forces on several different wheels.  To find out where the CLR is on your yacht, set it up on the ground and push it sideways with your finger.  Search for the place where the boat doesn't rotate as you push it.  It turns out that on a landyacht, under static (i.e. non accelerating) conditions, the center of lateral resistance will be the same as the center of gravity (CG), provided that the coefficient of friction for the front and rear wheels is the same.  The figure below shows the static force and moment equations for a landyacht.  

These equations show that the CLR and the CG are the same as long as the friction is the same for all the wheel.  If the friction at one wheel is greater than at another, then the CLR will be shifted towards the wheel with the higher friction.  Once you start sailing, the forces on the sail will have an effect on the weight carried by each wheel, which will also shift the CLR slightly.  That is why the static determination of the CLR may only be good enough for a first guess at where to place your sail for proper helm.  After that, you will probably need to experiment a little to find the position that gives you the helm you want.  

The length-to-width ratio (L/W) of a three-wheeled landyacht affects the righting moment available to keep the yacht from flipping.  This is because the moment arm (the distance from the center of gravity (CG) to the line about which the heeling yacht rotates) changes as the L/W ratio changes.  The figure below demonstrates this.  

The distance "d" in this figure is the moment arm and as you can see, as the yacht gets very long (L/W -> infinity) d approaches half the rear axle width (w/2).  As the yacht becomes very short (L/W -> 0), d approaches zero.  This relationship is demonstrated in the following dimensionless plot.  

The plot shows that for small L/W ratios, the righting moment arm increases quickly and then levels off.  Based on this analysis, you might think that the longer you make your yacht, the better, although most of the benefit is had once you get to L/W = 1.5.  It also shows that as the CG moves backwards, the righting moment increases.  However, the previous plot assumes that the CG can be moved independently of yacht length, but in reality the CG will move forward as the length increases.  Exactly how much the CG will move depends on the specific design of the yacht.  To quantify this relationship, the LS-3 design was chosen to determine the approximately relationship between length and CG position.  This next figure shows the normalized moment arm (d/w) when we account for the relationship between length and CG position (based on the LS-3 design).  

This shows a more realistic picture of what is happening as the L/W ratio changes.  Now you can see that the maximum righting moment arm is reached at an L/W ratio of about 0.8 to 1.3.  However, L/W ratios at or less than 1 have undesirable behavior because the fore-aft stability becomes an issue when the windward wheel begins to lift off the ground.  A good compromise is an L/W ratio around 1.3-1.5, which is a value commonly seen in full scale landyachts and models alike.  In fact, the IRCSSA class rules, when maxed out, result in L/W ratios of 1.3-1.5.  

More to come soon... And if there is an aspect of model design you would like to discuss, please send your suggestions, questions or comments to [email protected]

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KRIS SELUGA | MILFORD, CT | [email protected]

Top 5 Best RC Sailboats for Sale

Updated: June 4, 2021

RC Sailboats are an awesome hobby to pick up and make for hours of fun sailing. RC sailboats glide through the water, typically from electricity as a fuel source, and have pretty cool features and specs based on each model.

We’ve found top 5 best RC boats so you can find the sailboat that fits you best.

• Range: 14.86 M
• Time: 5 mins

• Range: 200 M

• Range: 15 M
• Time: 20 mins

• Range: 100 M
• Time: 10 Minutes

The Best RC Sailboats

We’ve found the best RC Sailboats for sale on Amazon and have created a review with the top 5 RC Sailboats and RC model Sailboats to help you find the best one for you.

Rage RC B1300 Eclipse

High-quality ABS molding

Reinforced, rip-stop nylon sails

Includes 4 AA batteries for transmitter

Dimensions 11 x 7.5 x 46.4 inches

Weighs approximately 11 lbs

Pros and Cons

Minimal assembly is required and batteries are included so you don’t have to wait to get sailing

Large model stands out amongst other boats on the water

The size may make it difficult to travel and transport

POCO DIVO RG65 Class Competition Yacht

Read reviews and show for the POCO DIVO RG65 Class Competition Yacht Here

650mm or 900mm sails

3kg winch servo

Waterproof, durable ABS molding

Takes 8 AA batteries

Dimensions 25.6″L x 5.3″W x 53.7″H

Weighs approximately 10 lbs

The size makes the sailboat easy to transport and great for pools, ponds, rivers, and lakes

The durable and waterproof molding keeps electronic componenents safe

Golden Bright Full Function Boat

Read reviews and show for the Golden Bright Full Function Boat Here

Sails are individually controlled

Takes 1 9 Volt battery and 4 AA batteries

Dimensions 20.3 x 4.7 x 33.7 inches

Weighs approximately 4 lbs

The motor makes it great for beginners learning to sail

The Golden Bright is a small RC sailboat, making it easy to travel with

Assembly is required and the batteries are not included Golden Bright manufactures great RC hobby toys. Their Full Function Boat is a small RC sailboat and so simple. It’s great for beginner sailors just learning, but intermediate sailors will love perfecting their skills with this boat too. Because of its size it is a budget-friendly option for remote control sailboats, but still with top-notch quality.

Kyosho Seawind

Detachable parts for easy transportation

Dimensions 40 x 9 x 73 inches

Weighs approximately 13.5 lbs

Easily detachable parts make transporting this RC sailboat a breeze

High-strength aluminum mast makes a durable boat

Intricate assembly required with approximately 1 hour of rigging and sail trimming

DragonForce 65 V6 Racing Sailboat

Read reviews and show for the DragonForce 65

Micron Mylar “A” sails

Upgraded digital rudder servo

Extremely durable hull

Requires 8 AA batteries

Dimensions 4.6 x 25.6 x 52.7 inches

Weighs approximately 6 lbs

Pros and Cons Fast and powerful

Designed for actual racing

The rigging process can take a while

This smaller RC sailboat is great for beginner sailors. It comes partially pre-rigged and is ready to race with only minimal assembly. It’s a fast, user-friendly RC sailboat that you’re sure to love.

Click To Shop or Read Reviews

Now that we’ve found all of the best RC Sailboat – top 5 RC Sailboat for sale, which one is your favorite? We’ve found a rig that is perfect for all different types of skill levels and preferences, so you’ve got the literal pick of the litter.

FAQs About RC Sailboats

If you do not see your question, or an answer to it, listed below, get in touch with us and we’ll happily give you one!

How do RC Sailboats work?

RC Sailboats work through radio control, which is a given considering the “RC” in the name, and a bit of skill. You need to steer, draw the sail, etc. Interestingly enough, it’s a lot like sailing a real sailboat, but you’re using a controller to do it.

This is where the skill part comes in. Drawing the sails, for example, requires timing and precision to ensure that you’re doing it properly. If you don’t, you face it sinking, should the model be a very extensive one, or not sailing properly at all.

Where can I race a RC Sailboat?

You can race a RC Sailboat virtually anywhere. Although, racing in the ocean may not be the best idea if you’re very invested, both emotionally and financially, in your boat.

This is where lines come in. A lot of users will have a line system to ensure that if there is a crash and their boat sinks, or whatever the case may be, they can still retrieve their vessel without actually having to go into the water.

Are there are RC Sailboats that use wind?

Yes! Some RC Sailboats do not use electricity or a motor as a source to run. Some only work with windy weather, but still require a controller for steering, drawing the sails, etc.

What happens when the wind stops?

This is another instance where a tow line comes in handy. If the wind stops you have two options – wait for it to come back, or use your tow line to reel it back in. Some users have small tugboats that are able to go out and retrieve a RC Sailboat that has a downed sail, has stalled, etc.

What if it tips?

If your RC Sailboats tips, it’s obviously not a very good one. The good quality ones have something at the bottom to ensure this doesn’t happen unless it’s hit by another one, has a hole in the side, etc.

It may tip into the water from the wind or have the bow go under water, but it should not tip on its side completely in any instance other than one of the reasons previously mentioned.

If it does tip, reel it in using your tow line or go into the water and get it.

Further Reading & Related Sites

Best RC Boats for Kids Electric RC Boats Boats for pools

Remote Control Sailboats For Sale

We hope this article has helped you find the best RC sailboats for sale in 2021. If you have a great sailboat we missed, or any questions about this topic we didn’t address, be sure to let us hear about it in the comments!

Kennedy Martinez

Kennedy Martinez is a resident writer who joined Dronethusiast at the beginning of 2019. She has years of experience reviewing drones and other tech products. When it comes to flying drones, Kennedy loves the ability to create artistic videos from a unique point of view. Kennedy enjoys researching new drones and other exciting products that are available to consumers which is why she is committed to creating the best buyer's guides for our readers.

There are 10 comments:

I would definitely go for K2 – manufactured by Sailboat RC company. That 1-metre hull beast won World AND European Championship, USA Nationals, Southern America Cup, Australian Nats…and all in 2017/2018 season!!

Check it out, it is outstanding piece of art really, a must have RC Sailboat.

I am looking for 1 mtr fibreglass remote controlled sailing boat preferably European or american.Thanks Annette

Hej! Have you found something? I search for a rc sailboat that I can transport with my bicicle.

Hi Annette, I too am looking for a 1 meter or 3 foot sailboat. Had a “Tradewinds” that was 3 feet long and loved it! BUT, the 5 pound center board weight (I used BB’s) was hard to find…. Want to get one so it can be sailed in the pond/small lake outside. A friend got one too and we used to “race”. But, we had no buoys – there are usually two or three and depends on the size of the boat.

In the Chicago area, Wisconsin, Chicago, Indiana (Munster), Michigan, and Florida (about 20 miles from Orlando) – we were lucky and I was sailing anywhere from 13′ to 45′ boats. People that did not know me were freaked out when I could sail.

Another boat makes sense here. And, if I had two, then another person can sail too. And, I can make buoys that are needed to race boats. Hmm, that is a good idea.

I am a former professional licensed Captain, sailboat dealer and racer who is now landlocked. Looking to start RC sailing, but prefer to identify key class associations, publications and such information to make sure there is a strong RC class or one design to guide me. Looking forward to guidance first, then back on the water the right way.

look up rc lazer,good sail boat spend the extra cash and get the “a” and the “c” sails the “a” sail needs the larger mask.it does come with “b” sail and mask.the travel bag is great.just got back from michigan brought the boat with and had a lot of fun with all the crazy wind on the lake.i live in chicago and its great 1m boat to take anywhere

My 18-year-old sails 420s and Lasers competitively, and is now asking for a r/c sailboat for Christmas. He has never used one before, but thinks the idea sounds fun. He is engineer-minded, grew up rigging and racing. We live on a bay off the ocean. Can anyone recommend a r/c sailboat $300 or less?

I am sourcing an RC catamaran (3’+-) and would like suggestions. Thx.

what about a orion?

Where can I purchase a large laser rc sailboat

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Build your own radio controlled yacht

Are you ready to embark on the exciting journey of building your very own model rc yacht.

Our comprehensive eBook has  clear building instructions and step-by-step photography for the Racing Sparrow 750mm RC Yacht.

What we cover in our boat building eBook

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Even those with limited building experience can join in on the fun with minimal materials and a simple toolset. Our eBook by New Zealander Bryn Heveldt covers strip planking, fibreglass strengthening, mould and casting techniques, electrics installation, spray painting and masking, sail making and tuning.

To get started on your Racing Sparrow model RC yacht project, purchase our eBook and download the PDF now.

Racing Sparrow blog

We share tips and stories from the model boat building community. See all Blog Posts.

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We provide a number of different boat plans that you can build using techniques covered in our full eBook.

You can download plans for boats of different sizes and specifications.

What our customers say about Racing Sparrow

Being a complete novice, I purchased your book a couple of years ago and built two racing sparrows. Building on this experience I then went on to build, from scratch, an IOM (Triple Crown design). I've since joined a local club and sail virtually every weekend. I would just like to thank you for your endeavours which have allowed me to enter a world I never thought was in my reach.

John Sterland, Australia

Coming upon your book, "Build your own Radio Controlled Yacht" in the Napier Public Library, I am hugely impressed. The combination of your superb photos and illustrations with your easy writing style make it a standout publication and I hope it does well for you.

Richard Spence, New Zealand

Thanks for an excellent design in your RG65. I trialled her again today in a solid 20 knots gusting higher. Even so in a steep chop and fingers off the rudder she drove upwind remarkably well, balanced perfectly. Very impressed that a model boat can handle that with a large rig. I found the book excellent. Ive built several big boats, plus a few skiffs and without that resource building such a good boat would have been impossible.

Mike Bennett

Boats built by the Racing Sparrow community

We continue to be amazed at the beautiful model RC boats created by Racing Sparrow enthusiasts .  Send your images to info@racingsparrow.co.nz.

Take a look at the full boat gallery  page. So many fine model yachts!

Martin Whittle, RS750 , UK

May 1, 2011

Kendal Allcott , Nelson, New Zealand

Feb 11, 2010

Bryn's fibreglass Racing Sparrow , Wellington, New Zealand

Sep 2, 2008

This red boat is the latest racing sparrow that we've built and put to the test. It has been built for wellington conditions. It has the maximum 1.3kg lead bulb. It has a basic deck structure, no plywood, 1 layer of balsa with a coat of resin-only to save on weight and budget. It uses the more basic hatch construction of plastic sheet taped on with ducktape, very effective and waterproof. The sails are maxed out, being cut very close to the plans, maybe a little bigger, there are no rules about max sail area in the class rules! Another difference on this boat is the mast has been painted black for a different look.

'Sparrow' based RG 65

May 2, 2020

More about Racing Sparrow

When I was nine years old my father, Ross Heveldt taught me to sail down at Bucklands Beach in Auckland. My wee optimist dinghy was called 'The Racing Sparrow', the nickname my uncle Bruce Curry gave to me when I was a small boy. Apparently I had an abundance of energy.

I studied at Whanganui School of Design and have been a designer / developer since 1998. I live in New Zealand.

Best wishes and happy sailing, Bryn Heveldt.

To contact me please email:  info@racingsparrow.co.nz

International Radio Controlled Surface Sailing Association

Welcome to ircssa.

IRCSSA, the International Radio Controlled Surface Sailing Association, was founded by radio control surface sailors to include both land and ice yachts because of the common sailing principles of the two vessels and the differences between them and other forms of sailing.  Its mission is to promote the sport and encourage the exchange of ideas with cooperation and friendly competition worldwide. 

*****************

To accomplish its mission IRCSSA intends to provide such things as Class Standards, a standardized Sail Numbering system and racing rules. It is not the intent to dictate what members do in their home countries. Rather, it is to provide in addition to local practice, standardized conditions in which members can compete with other members in other parts of the world, under identical conditions. Members can use any rules or conditions they wish when competing with local members, however when competing with members in foreign lands, IRCSSA standards will be available for them to use.

It is also IRCSSA’s intent to provide in this website, notice of sources for items useful for participating in this sport.

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Lee Valley Model Yacht Club's (Brief) Introduction to Radio Controlled Yacht Racing

Are you up to a real challenge?

Students Build and Sail a Radio-Controlled Model Sailboat

This first story is from Captain David Bill, Nautical Sciences Teacher at Tabor Academy in Marion, Massachusetts. Since 2008 Tabor has offered students a boat design and building course using radio-controlled, or R/C wooden sailboat kits. It has proven to be one of the most popular courses in the school (there is always a waiting list) because it satisfies a hidden need among today’s students raised in a digital world: The need to make something using their own hands and skills. In the process, they learn valuable lessons in math, chemistry, physics, problem-solving, teamwork and leadership. Some students even incorporate lessons in graphic arts into their projects.

by Captain David Bill

Edited by dan walker, national sailing hall of fame.

Radio-controlled sailboat models are not just fun to sail and build; they also serve as excellent hands-on teaching tools for several different lessons in maritime skills, math and physics… even in art!

Tabor Academy is a co-ed boarding and day school located on the water in Marion, Massachusetts. As the “school by the sea,” Tabor sustains a unique maritime heritage that embodies in all its programs the qualities that a seagoing life requires: Thoughtful preparation for and awareness of the wider world, perseverance, courage, good humor, a sense of direction, and humility.

A number of years ago at Tabor we decided to change our traditional year-long Marine Architecture class into a one semester class which allowed for more flexible student scheduling for this nautical science elective. This new class, which we call “Practical Ship and Boat Design,” includes teaching sailing theory, boat building, parts of the boat vocabulary, rigging, boat design and many other applications. Math, physics and other lessons easily work their way into the lessons learned from this class.

Building and sailing the model allows for numerous teaching moments and building real life skills. In our digital world, young people have an unconscious desire and need to learn hands-on skills, even skills as simple as constructing a wooden hull using two-part epoxy, or learning to wire controllers and configuring the running rigging of their boats. Many of our students have never sailed a boat before, and now here they are — masters of their own first command!

Concepts Learned – Math, Chemistry, Physics, Leadership, and Art!

After the boats are sailing, navigation concepts can pull in both the math and physics, as the students work to explore concepts of distance, rate and time, speed over ground, velocity made good, etc.

Since Tabor is a private boarding school, we are more free than most schools to develop our own standards and how they are applied. That doesn’t mean, however, that this class could not easily comply in with typical core curriculum standards found in most public schools. Given a motivated teacher and some thinking outside the box, there are many “tests” along the way in the building process:

Engineering: Did your epoxied pieces set up properly? If not, reasons why and what can be done to repair?

Architectural Design: Is your keel shaped for best hydrodynamic flow? Is your hull symmetrical or is there twist along the longitudinal axis? How will that impact your boat’s speed?

Leadership skills: If the boat is a group project, team leaders could be assigned for each step of the process, and encouraged to teach their part of the process to the others in their team.

Business: Extrapolate how this process would be controlled by a company in the business of building and marketing these boats?

Statistics: Given a set of performance data after several measured test sails, develop a statistical model that could be used to rate and handicap each student’s boat, then race the boats using the handicaps; are the statistics fair and consistent?

There are several sizes and types of radio-controlled sailboat kits available. In addition to cost, factor in the place where you will be having your students sail their finished boats. Places with more wind need a larger boat; I’ll talk about why later on.

We use a T27 model sailboat kit, available online from Tippecanoe Boats: https://www.modelsailboat.com or http://www.tippecanoeboats.com. The cost for the complete kit, which includes radio control equipment, sails, zinc ballast — everything except batteries and materials to paint or varnish the boat — is around $240 per boat (likely the least expensive racing boat anyone will ever own!). Tippecanoe Boats has both larger and smaller kits, ranging in cost from $49 for a T12 (a 12” boat without radio controls that can be sailed with a light line and fishing reel (for retrieval purposes) all the way up to the T65, weighing in at almost 5-1/2 feet long, 12 pounds of weight and costing $895 each. They even have a trimaran and a US Venom One-Metre class racer, which has a carbon fiber hull! Enough day-dreaming…

Other companies also make wooden model sailboat kits:

• Chesapeake Light Craft ( http://www.clcboats.com/shop/boats/wooden-sailboat-kits/independence-remote-control-sail-boat.html ) sells a 48-inch long wooden Independence R/C boat kit for $199 for the wood parts, plus costs for epoxy and wire kits. You will still need to source the sail material —  rip-stop nylon makes a good model sailboat sail, and is readily available from fabric store chains like Jo-Ann Fabrics.
• Another potential source for both boats and advice is the American Model Yachting Association: https://www.theamya.org. Radio-controlled model yacht racing has several one-design classes, and the competition can get as serious as the big boys, with yacht prices to match… even for a model! That said, every class of boat has a low-cost entry point, and model sailboats are no exception. Google “wooden model sailboat kits that sail” or “DIY model sailboat kits” – I’ve seen model kits available for as low as $29.
• If you are more creative, and your school has the resources and tools to allow students to shape the wood themselves, you could encourage them to apply what you’ve taught about hull design. Let them shape their own unique hull design from blocks of balsa or other light, easily workable wood, available at hobby stores, finishing it off with keels and sailing rigs made either from pre-built rig kits or materials of your own sourcing.
• For elementary schools with “Maker Labs,” Oriental Trading sells DIY wooden sailboat kits for $19 that contains all the components to build a dozen 7.5-inch sailboats good enough for a “Rain Gutter Regatta” – that’s $1.58 per boat! For kits like these, you could use non-toxic wood glue and instead of epoxy to assemble, and fabric markers, wood markers or even crayons to decorate, making this a project even for younger grades. http://bit.ly/STEMsailing-DIYtoyboatkits

Workshop as Classroom

Students should be dressed appropriately: Have them wear clothes they don’t care about, and bring in old long-sleeve shirts that can get ruined; they can keep them at school with their boat projects. Boiler suits, shop aprons or disposable Tyvek suits could be useful — see if you can get some donated.

The Lessons

The model building period, from start to finish, spanned a time period of eight weeks, with one 40-minute class per day, five days a week. Of course, a single model built by a skilled individual could be accomplished in far less time, but the timeline for our students’ model building was governed by the school class schedule and other commitments they have in their normal school day.

All work on the boats was done in class. Nightly reading was assigned from the instruction manual so students will have a step by step understanding of what we will accomplish the following day.

An important engineering skill set involves learning how to read and follow a technical manual. By following the detailed instructions, they quickly learn these skills. And sometimes, when in the course of learning the students make mistakes, they learn another important skill: Problem-solving.

Obviously, since materials like epoxy, paint and/or varnish are used, safety procedures must be first taught and then supervised to ensure that any mistakes don’t result in a mess, or worse.

If possible, you might want to build one of the boat kits ahead of the class, so you can have firsthand knowledge of what is involved and the time that you should plan in for your students to perform the same procedures. Since it takes time for things like epoxy and paint to cure or dry, plan on either finishing a class so the boats can dry overnight, or use that time for cleanup, group discussion or introducing the next concept.

This IS Possible for Land-Locked Schools

Our students sail their boats on the waterfront that is part of our campus, but you don’t need to be near waterfront property for this to work. The beauty of radio-controlled boats is that they can be sailed on any body of water — including shallow ponds and lakes. I’ve heard that inland folks even sail their boats in indoor swimming pools utilizing fans for a wind source.

End Result: A Fleet of Sailboats!

It would be possible for teams of students to work on a single boat, treating the costs as either a “lab fee” or using PTA or school funds for the materials. I would guess in those cases that the boats would be school property.

You could display them and use the best ones as reference boats for next year’s class, hold a competition where students vie to win the boats, or offer them as a reward for students who provide additional volunteer assistance or some other good work that is “above and beyond.”

And a School Regatta!

Where your students will sail the boats should factor in to what type of boat you have the students build. Just as it is for any sailboat, a general rule is that the greater the LOA (Length Over All) of a radio-controlled model sailboat, the greater its ability to sail and manage higher velocity winds.

Conclusions

The big success of the Practical Ship and Boat Design class is because each student can build and sail their own boat. They take complete ownership of the boat, connect with the hands-on aspect of the work, and they are very proud of the finished product. Plus, the boats are VERY fun to sail.

After eight years of teaching this class, the result is that there is a waiting list to get in. Sometimes a student must wait patiently for two or even three years in order to get a spot in this class.

My students tell me that it is their most challenging class (but also favorite) because they have to think and problem solve on their own.

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Payne: Sailing the screen-tastic Lincoln Nautilus land yacht

Palm Springs — Welcome to the 2024 Lincoln Nautilus. Call it the Lincoln Not-like-any-cabin-you’ve-seen-before.

A handsome, high-definition 48-inch screen wraps the front cabin from A-pillar to A-pillar. Like the twin screen sitting on your office desktop, its expanded space allows you to run multiple applications. Which means you can keep your eyes on the road while scanning information including speed, navigation map, Sirius XM channels, range and more.

Cruising hands-free in Blue Cruise down Interstate 10, I rested my hands on my knees and settled back in the comfy leather thrones. Ahhh, a comfortable day at the office.

With its emphasis on quiet luxury (current slogan: “Power of Sanctuary”), Lincoln has been about comfortable cabins rather than carving corners. Let Bimmer, Alfa and Caddy fly around Nürburgring setting lap records, Lincoln wants to fly you First Class. Now, with its Lincoln Digital Experience, the brand has created a high-tech environment to rival other transformative interiors from Tesla Model S, Mercedes EQS and Cadillac Lyriq.

I first saw a pillar-to-pillar design on the Byton M-Byte, a Chinese electric vehicle, at the 2018 Los Angeles Auto Show. It was a showstopper. Byton promised its 48-inch jumbotron would come to market in 2020. Didn’t happen.

With Nautilus, this is Lincoln’s chance to shine. At a dealer in North Miami Beach recently, I heard audible gasps from customers as they opened the Nautilus doors. I haven’t seen butts jump into seats so fast since the Model S screen wowed at the 2010 Detroit Auto Show.

Tesla opened boutique stores at high-end malls (think Somerset) across the country so casual shoppers could try on their interiors as easily as fitting pants at J.McLaughlin. Lincoln, which has dabbled in the boutique store market, should do the same.

The 48-inch display works as well in practice as it looks. Like a TV screen paired with remote control, the touchless jumbotron is controlled via a console-mounted 11-inch tablet. Lincoln’s native navi system is run by Google — like Android Auto — and either can be used in the panoramic display’s center.

“Hey, Google, navigate to Idyllwild,” I barked, and the route populated the command tablet and megascreen. I gripped the wheel and eased into Palm Springs traffic for my trip to the San Jacinto Mountains.

The simple steering wheel (Tesla simple and square like a Corvette C8) is slick. It’s squared-off so as not to obstruct the megascreen. Like a head-up display, instrument and navigation information is always in your line of sight. The wheel’s simple interface is anchored by twin touchpads (Tesla uses scroll wheels): volume on the right, adaptive cruise control to the left. It shames over-engineered, button-infested wheels like Mercedes.

My instinct was to glance at the closer console pad for directions, but, with time, my eyes focused on the big screen. Its right half contains three more “pages,” which I filled with radio, trip information and clock. Want to change the selection to include tire pressure? Simply drag ‘n’ drop the icon on the command screen and — bingo! — it's mirrored on the megascreen. A muscular Qualcomm chip makes for smartphone-fast touch speeds, a key to Tesla’s early popularity.

Also like Tesla, the Lincoln system is so cool you forgive Nautilus its dissonate notes.

Lincoln’s engine lineup is weak compared to competitors like Genesis and Mercedes (more on that later). Blue Cruise drive assist is sketchy — turning off multiple times during my interstate test. And there’s a wonky Drive Mode button on the console that doesn’t actually control the modes — it just gives you access to them in the command screen. It’s an awkward process not unlike Tesla’s two-button chore to open the glovebox. Happily, most Lincoln drivers will rarely use SPORT mode. Nautilus is no BMW M4.

Like the Bimmer, however, Nautilus is gas-powered. Lincoln teased a Star Concept EV two years ago, but has resisted the Sirens’ call to full-electrification like other small premium brands. Instead of tearing up its playbook, Lincoln’s refining it.

Nautilus’s state-of-the-art interior is executed atop a familiar gas-powered drivetrain lineup. Customers (Nautilus is part of an SUV family including Corsair, Aviator and Navigator) prize the “utility” in sports utility vehicle for summer trips up north or out west.

For all of Tesla’s innovation, the Silicon Valley brand copied Lincoln’s electronic button transmission for its 2024 Model 3 Highland. Tesla’s shifter buttons, naturally, are in the screen, whereas Lincoln offers hard buttons on the console. I played them like piano keys, shifting the DRIVE button with my middle finger and the REVERSE button with my forefinger as I backed in and out of a parking space.

Once on the road, my hybrid turbo-4 cylinder purred along — a distant heartbeat from the hush-quiet cabin wrapped in acoustic glass and insulation. Despite the premium ride, the engine is Nautilus’s weak link.

The base 2.0-liter sounds like the Ford Escape egg-beater it’s shared with, and the hybrid lacks the visceral authority of a Detroit machine. Genesis, Acura, BMW — even Mazda’s premium CX-70/CX-90 — offer six-cylinder mills. Lincoln follows Lexus to hybrid fours, and it’s worth the $1,500 upcharge over the base engine. Coupled with a smooth CVT transmission, the battery provides good low-rev torque-fill to offset turbo lag.

Also worth the extra cents are the seven cabin scents on offer.

The electronic scent cartridges — standard Mystic Forest, Ozonic Azure, Violet Cashmere and additional Cloud Balsam, Serene Seashore, Twilight Embers and Sunlight Retreat — are loaded, three at a time, into a hidden chamber beneath the armrest. I hesitated at dispensing them, fearing my cabin would be doused in incense.

But the odors were mild and pleasant and complemented my refreshing interstate drive.

Passengers will enjoy the ride, too, as Nautilus offers best-in-class rear legroom (43.1 inches) and a giant panoramic roof so they can enjoy the treetops/sky/stars overhead. The hybrid’s 600-mile range will get you to Mackinaw City and back without ever having to stop at a gas station. Or, ahem, sit at an electric charger.

This rolling yacht is wrapped in a bold Lincoln exterior, including soft-squeeze, Packard-like door handles along the shoulder line. Mirroring the brand’s signature horizontal rear taillight, the front LED lamp now wraps ‘round the front. Lincoln also is hell on wheels (remember the turbine wheels on the Navigator?) and offers head-turning 22s that come with the Jet Package.

Big as it is, Nautilus sweats the little things.

Start with the door handles, then note the no-cap gas filler and double-pull hood tab under the dash so you don’t have to fish around the engine bay for the hood latch.

Buy it and you’ll be that guy giving neighbors interior tours.

Next week: 2024 Ford Ranger

2024 Lincoln Navigator

Vehicle type: Gas-powered, all-wheel drive, five-passenger luxury SUV

Price: $52,210, including $1,595 destination charge (as tested)

Powerplant: 2.0-liter, turbocharged inline 4-cylinder; hybrid-electric drivetrain with 2.0-liter, turbocharged inline 4-cylinder

Transmission: Eight-speed transmission (2.0L); CVT (hybrid)

Weight: 4,517 pounds (hybrid, as tested)

Power: 250 horsepower, 280 pound-feet torque (2.0L); 295 horsepower, 310 pound-feet torque (hybrid)

Performance: 0-60 mph, NA; towing, 1,750 pounds

Fuel economy: EPA est. 21 city/29 highway/24 combined (2.0L); 30 city/31 highway/30 combined (2.0L);

Report card

Highs: Inspired interior tech, roomy, detailed design

Lows: Uninspired 4-cylinder engine lineup; Blue Cruise a work-in-progress

Overall: 4 stars

Henry Payne is auto critic for The Detroit News. Find him at [email protected] or @HenryEPayne

SU: Radio Catalog for the radio manufacturer Chayka, Moscow

RC Pond Yachts for Sale: A Beginner’s Guide

• By - Kyle Hilson
• Posted on November 14, 2023 November 15, 2023
• Posted in RC Boats

If you love sailing but live far away from the coast or a large body of water, an RC pond yacht might be the perfect solution. These miniature boats give you a taste of the experience of controlling a boat on the waves or in a lake without the need for a large body of water. They’re perfect for backyard ponds or small lakes near your home. Unlike full-sized boats, these models are lightweight and easy to transport, which allows you to take them wherever you go. RC pond yachts come in various sizes, ranging from 1 to 4 feet in length, allowing you to choose the one that suits your space and sailing needs. Some models also feature wind-powered sails to simulate real sailing, adding to the experience. If you’re new to RC pond yachts, there’s no need to worry; these boats are relatively easy to operate, and most come with simple controls that let you steer the boat around the water with ease. With the right model and a bit of practice, you can quickly become an expert skipper, mastering the wind and waves and enjoying everything that sailing has to offer.

Benefits of RC Pond Yachts

There are many benefits to owning an RC pond yacht for sale , including:

• Low maintenance costs compared to full-sized boats
• Relatively affordable price point for beginners
• Easy to transport and store
• Ability to operate alone or with friends for socializing
• Provides an excellent way to relax and de-stress

To get started with RC pond yachts for sale , there are a few models to choose from. The Pro Boat Ragazza 1 Meter RTR Sailboat is a popular choice, featuring a durable fiberglass hull and a 2.4GHz Spektrum radio system. Another great option is the Joysway Mad Flow F1 Brushless RC Boat, which offers a fast and nimble design that’s perfect for racing. RCPlanet.com and HobbyKing are popular online stores that offer a variety of RC pond yachts for sale models to choose from. Whichever model you choose, you’re sure to have a ton of fun sailing your boat in the pond or lake near your home.

How do you control a RC sailboat?

To control an RC sailboat, you need to use the transmitter channels and controls. For RC sailboat controls, the side channel typically used for throttle on an airplane controls the sails. You can draw the sail in or let it out by moving the left side stick vertically. The right-hand side stick controls the rudder on the RC sailboat. For more information on radio control, you can visit the Wikipedia page on Radio Control. Some products that can be helpful for controlling RC sailboats are the RC sailboat kits available on Amazon and hobbyist websites like Horizon Hobby.

Considerations When Choosing an RC Pond Yacht

When shopping for an RC pond yacht for sale , there are a few things to consider to ensure you find the right model for your needs. Some factors to keep in mind include:

• Size: Consider the size of the boat and the size of the pond you’ll be sailing in. A larger boat may be more difficult to maneuver in a smaller pond, for example.
• Materials: Look for boats made with high-quality materials, such as fiberglass , to ensure durability and longevity.
• Design: Consider the design of the boat and choose one that fits your style preferences. Some boats have a more classic look, while others have a modern, sleek design.
• Price: Decide on a budget before beginning your search to ensure you find a model that fits your price range.
• Accessories: Look for boats that come with all the necessary accessories like radio , receiver , batteries , and charger . Some boats also come ready-to-run (RTR) which means they are fully assembled and require little setup time.

It’s also important to note that some RC pond yachts can be customized with additional sails or graphics, so be sure to choose a model that can be modified to your liking. Additionally, there are a number of online forums and communities dedicated to RC pond yachts, where you can find tips, advice, and even meet other enthusiasts.

Below is a table comparing the specifications of two popular RC pond yacht models:

How to choose a yacht?

Choosing a yacht involves deciding the kind of motor yacht that will meet your needs, considering the amenities and narrowing down a size range. It is also important to try before you buy by conducting a sea trial. Working with a dealer or broker who understands your needs is helpful. It’s essential to set a budget and stick to it. Also, take a boating safety course before setting sail. For more information, check out yacht manufacturer websites or speak with a yacht dealer or broker.

Final Thoughts

In conclusion, owning an RC pond yacht can be a fun and rewarding hobby for those who love sailing but don’t have access to a larger body of water. By considering the size, materials, design, price, and accessories of different models, you can find the perfect boat for your needs and preferences.

One great option for those just starting out with RC pond yachts is the Pro Boat Ragazza 1 Meter RTR Sailboat. This boat comes fully assembled and includes all necessary components like a 2.4GHz Spektrum DX2E radio, Li-Po battery, and charger. Plus, with its classic design and realistic sail, it provides an authentic sailing experience.

For those looking for a smaller, more maneuverable option, the Joysway Mad Flow F1 Brushless RC Boat is a great choice. This boat features a lightweight design and powerful brushless motor, making it ideal for racing and maneuvering.

Overall, there are a wide range of RC pond yachts available for purchase, each with their own unique features and capabilities. By doing your research and considering your needs and preferences, you’re sure to find the perfect model for a fun and exciting sailing experience in your local pond.

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Middle East latest: Explosion in Red Sea near Yemen; Biden backs US leader who said Netanyahu must go

The United Kingdom Maritime Trade Operations has said a vessel has reported an explosion 65 nautical miles west of Yemen's Hodeidah. Meanwhile, Joe Biden has backed the US Senate leader who said the Israeli PM was an obstacle to peace and must go.

Saturday 16 March 2024 00:15, UK

• Israel-Hamas war

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• 'He made a good speech': Biden backs US leader who said Netanyahu must go
• Explosion in Red Sea near Yemen - report
• Israel warned by Germany over offensive in Rafah
• IDF claims armed 'terrorists' killed civilians 'looting trucks' - and criticises Hamas 'smear campaign'
• Group claims it was Israeli soldiers who killed at least 29 waiting for aid
• Alistair Bunkall:  Differences remain on ceasefire deal - but gap is narrowing
• Explained: What did Chuck Schumer say about Netanyahu?

We'll be back soon with all the latest updates on the Israel-Hamas war.

The families of hostages in Gaza have been marching in Tel Aviv today to call on the Israeli government to agree to a ceasefire deal.

Prime Minister Benjamin Netanyahu has been criticised by the families for prolonging the war instead of negotiating a deal.

Further to reports we brought you earlier of an incident 65 nautical miles west of Yemen's Hodeidah (see post at 8.48pm) we are now receiving more information.

The United Kingdom Maritime Trade Operations (UKMTO) has said the master of a merchant vessel reported an explosion a distance off the vessel's starboard beam.

"There is no damage to the vessel and the crew are reported safe. The vessel is continuing to its next port of call," UKMTO added in an advisory note.

Months of Houthi attacks in the Red Sea have disrupted global shipping, forcing firms to re-route to longer and more expensive journeys around southern Africa, and stoked fears that the Israel-Hamas war could spread to destabilise the wider Middle East.

The US and Britain have carried out strikes against Houthi targets in response to the attacks on shipping.

Back to the offloading of aid in Gaza now and the World Central Kitchen has shared a video of cargo being offloaded.

The US-based aid organisation said almost 200 tonnes of rice, flour, proteins and more "arrived by sea earlier today".

It has said a second vessel is preparing to set sail from Cyprus with "hundreds more tonnes of food".

The UK Maritime Trade Operations has said it has received a report of an incident 65 nautical miles west of Yemen's Hodeidah.

Authorities are investigating the incident, the UKMTO said.

Today we have been reporting on Israel's approval of a potential ground operation on the Gaza city of Rafah.

But global allies and critics alike have urged Benjamin Netanyahu to hold off attacking Rafah, for fear of mass civilian casualties.

Looking at the move, our  military analyst Sean Bell  has said the region is "packed" and "dense".

"How an earth you can do a military operation and differentiate between where Hamas are, where the civilians are and even where the hostages are? It would be a nightmare," he said.

"And if they were to do airstrikes, which has been part of what the IDF have been using, it would have devastating consequences for the people on the ground."

You can watch Bell's full analysis here...

The White House has expressed cautious optimism about a proposal from Hamas on a Gaza ceasefire-for-hostages deal.

The proposal has been presented to mediators and the US and includes the release of Israeli hostages in exchange for Palestinian prisoners, 100 of whom are serving live sentences.

White House national security spokesperson John Kirby said the proposal was "certainly within the bounds in broad brush strokes... of the deal we've been working on now for several months".

"We're cautiously optimistic that things are moving in the right direction but that doesn't mean that it's done," Mr Kirby said.

After Israel approved plans for a Rafah military operation, our  Middle East correspondent Alistair Bunkall  has said it is unlikely that a operation will happen imminently.

He said the Israelis have "always been clear" about their military operation in Rafah and argued they need to do that in order to dismantle Hamas's infrastructure and gain a victory. 

"They have never wavered from that," he said.

"The Israeli military have been drawing up plans about how that would work and how they would evacuate the people who are now in Rafah."

But Bunkall noted this is "not going to be a simple task".

He added: "It may be a credible plan in America's eyes but it will be difficult to implement.

"I think it will take time so I don't think we are looking at an imminent ground invasion of Rafah."

He went on to say the announcement of a ground operation in Rafah was Israel's way of showing "they are going to keep military pressure up".

As detailed here earlier, reports in Israel suggest Benjamin Netanyahu has approved plans for military operation in Rafah, where more than one million people in Gaza have fled after being previously ordered to do so by Israeli authorities.

The plan would reportedly include people being evacuated from Rafah itself, despite large swathes of the enclave having been devastated by Israeli bombardments.

While Germany has been largely supportive of Israel throughout its military operations since 7 October, it's foreign minister issued a warning following the latest reported development.  

"A large-scale offensive in Rafah cannot be justified," Annalena Baerbock said.

"Over a million people have sought refuge there and have nowhere to go.

"We need a humanitarian ceasefire now, so that the dying ends and the hostages are finally released."

It comes after US Secretary of State Anthony Blinken said Washington had not yet seen a clear and implementable plan for how civilians would be protected in the event of an Israeli offensive in Rafah.

The IDF has issued an update on the aid ship from Cyprus, which in the last few hours arrived in Gaza.

They said the ship contained 130 pallets of humanitarian equipment and 115 tonnes of food and water, which were transferred to 12 World Central Kitchen trucks and accompanied by IDF naval and ground forces.

"The vessels and goods underwent comprehensive security inspection," the IDF added.

They also emphasised that "the delivery of humanitarian aid does not affect the maritime blockade". 

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