RC Yachts for the model aviator

Yachts are different

If you've never tried doing any kind of rc model sailing, then you'll find that yachts are different. In pretty much every way.

It's all about racing

While there are races for model aircraft, they aren't even the bulk of competition types, with aerobatic and precision competitions being common. Not to mention that scale aircraft are as popular if not more so than competition aircraft.

Model yachting is primarily about racing. Things that don't contribute to speed are generally considered a minus. For most yachts, looks take a definite second place to performance, and the only acceptable visual tuning is hull paint. Possibly some sail coloring, but the number needs to be easily visible for races, which tends to limit that.

There are modelers who are interested in remote controlled scale models of sailing ships. They tend to favor historical models, as those have more structure and other things to experiment with. This part of the hobby is called scale sail or minisail, but I'm going to talk about model yachts.

Terminology

Just as with aircraft, there's lots of new terminology. Lots of it isn't new, just used in different ways, because the early aviators borrowed terminology from sail. So a rudder is still a rudder. Further, people have been sailing for as long as we've been keeping records, and the terminology has seeped into the language in ways that surprised me. So here's some common terms in topological order. I've tried to include all the ones I'm going to use.

bow
The front of the ship.
stern
The back of the ship.
starboard
The right side of the ship.
port
The left side of the ship. I actually prefer the archaic larboard.
helm
The steering mechanism or direction the ship is heading.
lee
Away from the wind, as in lee side - the downwind side of the ship, or lee helm - an undesirable tendency of a ship to turn away from the wind.
weather
Into the wind, as in weather helm - a tendency to turn into the wind, a little bit of which is desirable.
sail
A large sheet that interacts with the wind to propel the boat.
mast
The large post to which the sails are attached.
boom
A spar at right angles to the mast at the bottom of the sails.
mainsail
The large sail behind the mast of a yacht.
foresail
A sail in front of the mast of a yacht.
jib
The most common foresail for a yacht.
line
A cord connecting two parts of the yacht.
rigging
The various devices used to propel the yacht: masts, booms, sails, and the lines connected to them.
running rigging
The rigging that is changed to control the ship.
sheets
The lines in the running rigging. An RC yacht normally has two sheets, one for the mainsail and one for the jib. Both are usually controlled by one servo.
standing rigging
Rigging that is not usually moved during sailing. It can usually be adjusted to tune the ships handling.
stays
The lines that are part of the standing rigging.
forestay
A stay running to the bow.
backstay
A stay running to the stern.
shroud
A stay running to the side of the ship.
keel
A blade extending downward from the hull to counteract the sideways force of the wind on the sails.
ballast
A weight at the end of the keel to stabilize the yacht.

Controls

Unlike other vehicles I've dealt with -'copters, aircraft, cars/tanks/etc, and even hovercraft - there isn't a simple correspondence between stick motion and model motion, no matter how convoluted. About the worst I've dealt with is aircraft, where the controls control orientation, not motion, but that still just means learning how to think in terms of orientation. Maybe gliders - which I have no experience with - are different.

Ok, the rudder on a boat is similar - it tries to turn the boat. If you're not making steerage way, it may not succeed, but it at least tries. However, the throttle stick controls the sheets. Sometimes, moving the throttle up - which I have configured to let the sheets out - will cause the boat to start slowing down, other times it will cause it to speed up. Ditto for moving the throttle down, with the added bonus of sometimes causing the boat to heel over until the sails are almost in the water. It all depends on the orientation of the boat with the wind.

Setup

Setting up surface vehicles is straightforward, at least in my experience. Mostly it's a matter of getting the steering trim right. Most aircraft aren't a lot more complicated. You have more trims to get right, as well as the biggie of getting the CG in the right place. 'Copters will need the blades balanced. But these are all things that are either right or not, and can be done on the bench. Much of the control of how an aircraft flies is done at part selection time, not during tuning.

A modern flight controller has a slew of PID values that can be tuned. Most commercial models come with those already set, and they may not be adjustable. They are adjustable on stand-alone flight controllers, but most models should fly ok out of the box. These will have a range of values that fly ok, but you can tune them to change the flight characteristics of the aircraft. And if they aren't tuned, you'll need to fly the thing to figure out how to adjust them.

On a yacht, you can adjust - for each sail - the two end points of the sheet control, as well as the tension along the edges of the sail. You can adjust the top of the mast back and forwards by adjusting the tensions on the fore and back stays. Further, you may be able to adjust the position of the bottom of the mast. These things all affect the shape of the sails, which have all the properties of wings. Contemplate for a minute what tuning an airplane would be like if you had to tune the shape of the wings and stabilizers to the CG instead of vice versa. While you can tune some of these things on a bench - provided your bench has a bathtub - most of them require actually sailing the yacht. They all affect how the boat handles in different conditions, and they all have a range of values that can be considered "right". And this is on a simple, entry-level, ready-to-sail yacht!

Transmitters

There aren't very many transmitters designed specifically for yachts. For that matter, there aren't very many designed specifically for rc marine vehicles, and rc power boats are far more popular than rc sail boats. While you can use surface transmitters, having to keep a trigger pulled in to adjust the sheets properly just seems painful. The transmitters sold with RTS yachts are basically aircraft transmitters, with two sticks that are free to move in two directions, and all but one vertical direction having springs to keep them centered. The latter is the sheet control, and the rudder control is the horizontal direction on one of the two sticks.

One odd thing about these is that there is disagreement about whether the sheet channel should be reversed or not. The safest - for the model - setting for the sheets is all the way out, so there is an argument that this is where the the sheets should be when the throttle is all the way down. But to some people - me included - moving the throttle away from you feels like it should let the sheets out, so you want the opposite behavior. Different models from the same manufacturer will do it different ways!

Many people use cheap aircraft transmitters, as most of the adjustments you can make on a computerized transmitter are unnecessary, if not meaningless, on a yacht. After all, being able to set up elevon mixing doesn't help much if you don't have elevators or ailerons. I recommend a Devo 7E using the deviationTx firmware, as it provides a power through flexibility that's agnostic to the craft type, rather than with lots of craft-specific features.

Batteries

Batteries are one of the things where rc yachts are a clear win. All these things with motors need some hefty battery to drive the motor. Run times will be limited by that battery, and will be measured in minutes. An RC yacht just needs a receiver battery, and you should get hours of use out of one. You may want to bring along a spare in case you run out, but it's not required if your battery is freshly charged.

Failures

One of the nicer differences is what happens when things fail. A failure in your gear - letting the battery run down, having a servo fail, or some control stop working - just leads to the boat drifting back to shore, where you can go get it. That's about the worst that happens even if you dumb-thumb things, unless the boat develops a leak. In that case, you might sink, but most boats can be modded to avoid that by filling them with some kind of floatation material. Even if it sinks, if you can recover it much of the kit will still be usable. Your electronics is most at risk, as opposed to an aircraft crash where it's the body and framework that's most at risk.

How to get started

Ok, so this sounds interesting. Now you want to know how to get started. Doing this is no different from aircraft, except that there's no analog to the cheap micro and nano 'copters that you can fly indoors.

Local resources

As with aircraft, getting something that you can get local help with is a good idea, so the best way to start is to find a local club and see what they're doing. The largest organization in the US is the American Model Yachting Association, and there are similar organizations in other countries. Just like at an airfield, once there you should be able try piloting a few. Probably more, since accidents don't typically lead to rebuilds. That also means that buying a used model yacht is much less risky than buying a used model aircraft.

Of course, if there is no local club, the local hobby shop may have some expertise, and is worth checking out.

Internet resources

I'm not going to list any specific forums, because there are lots of them. If you regularly use a general RC forum, they may well have an rc yacht or sail section - or several. There are also specialized forums for brands, racing classes, and specific boat types.

Of course, you can find videos reviews, written reviews (check my rc blog for some), tutorials, tuning tips, and even books on the subject on the internet. One problem is that yachts are such complicated systems that you often find multiple solutions to a single problem - and both or neither may work for your issue, depending on what's actually causing them. Because of this, I haven't found a single How to fix your problem type guide, or even a single good tuning guide. There are some very good guides for specific models, but when they ask you to adjust things you can't adjust, I sort of lose interest.

What to buy

Again, the best choice is your favorite among the choices popular at your local club. Beyond that, and again like aircraft - or at least like they used to be - there's a trade off with size. Larger is generally better. Larger yachts are more stable, have fewer problems from scaling issues, and it's easier to figure out what's going on with them. However, they cost more, require more storage, and in extreme cases won't fit in your car. They also require a bit more room to maneuver in, and more depth, which could be a problem if you're not sailing at a club pond.

Toys

There are a lot of what model yachtsmen refer to as pool toys available, which model aviators would call toy-grade models. These can be recognized by many of the indicators that work for aircraft. In addition, anything that has a propeller should certainly be discounted, as that shows lack of trust in the ability of the craft to sail well.

Non-functional scale items - rails, wheels, possibly even life vests - on a model yacht are a bad sign, as yachts are generally about performance. These items don't contribute to that, and may well foul the rigging.

Low-cost options

A number of Chinese hobby companies make inexpensive models that have been labelled as anything from "cheap junk" to "nice inexpensive models after you fix the flaws". These are the source of most of the yachts you find on sites like Hobby King. They also have brand-specific forums. While I don't have anything against these and will probably buy one at some point, one hasn't been the right choice for me yet.

Low-cost Ready-To-Sail options

The next level up belongs to companies like Joysway. They have been characterized as RTS versions of the previous category with better quality control. They probably still have issues, but not quite as many and probably not as serious. Also, they tend to be sold complete, with radio gear and ballast weight in the kit. I've bought a number from Joysway, and will talk about some of those.

Joysway has been pushing the lower bound on size limits. As of this writing, their Dragon Force 65 is a very popular class-compliant yacht. At only 650mm long, it's a size that you can still find recommendations against buying because that's just to small to sail well. Cost is about US$180.

Going down a size, the Orion uses a lot of the Dragon Force rigging, but scaled down so they could sell it with the sails already rigged and displayed in the box. You still have to attach the rudder and keel, but the rigging is what looks cool in the box. It's brand new, but early opinions are that it sails well once properly set up. Can be found for US$100 on sale.

Finally, the Caribbean is so small as to not be much of a yacht. None of the rigging is designed to be adjusted, and looking like a boat instead of a pod with sails was clearly a design priority. This is a pool toy, including features like scale rails, wheels, benches and even a table. It even has shrouds, though neither of the larger two yachts do. Supposedly a lot of fun for the price, it's also popular for tweaking to add scale features, as it's the same scale as all that O-scale model train gear. It's normally US$60, but I found it on clearance for US$30. I haven't gotten it wet yet, but check my blog for the review after that happens.

More serious models

The previously mentioned Orion provides an inexpensive option if you just want to sample the hobby, but will probably lead to buying a second yacht soon. The Dragon Force 65 is probably the least expensive option if you're serious about model yachting. Prices can go up quite a bit from there, especially for the larger models. Even those that are smaller - the Micro Magic and Footy classes - tend to cost more than the Dragon Force. Many of the improvements you get with these boats are specific to competition as opposed to spending a lazy day at the pond.

Summary

Model yachts are different. They are challenging and a lot of fun. If you have a place to sail, I definitely recommend trying them out.