Yes. The website and the online calculator are free. All that we ask is that you become a registered member first. Subscribers unlock additional functionality in the calculator.

Registering is free and easy. Registered users gain access to thousands of preloaded components (motors, etc) and can save their data for later use.

Registration also allows us to keep you informed of major changes and new features. Expect emails no more than once a month.

Subscribers gain access to the component filters and the PowerEnergy per unit of time. Common units include the watt and horsepower. System Optimizer. To learn more about these features, please look at the tutorials.

By subscribing you help us continue to improve the calculator. Subscriptions cost just $19.95/year.

The goal of this website and application is to provide you with information so you can make informed decisions regarding your flying models. We do not say “do X”. We say “if you do X, this is what you might expect.” Ultimately, it is up to you to act or not act on our advice.

Unfortunately, no. If it were a bug in the calculator, I would be able to fix it. I depend on Adobe Flash Player, your Internet browser and the graphics card driver on your PC to correctly handle the display of the calculator screen. This sometimes does not happen. My advice is to first make sure you have the latest versions of all of these applications (Adobe Flash, Internet browser and graphics card driver). Adobe also has a technical note that might help.

The Data Server setting controls which Content Distribution Network (CDN) is used in connection with your account. A CDN is a network of servers that behave as one very fast server. When a data transfer request is made, the server that is physically closest to you is automatically chosen. Data updates are transparently mirrored throughout the rest of the CDN.

RCadvisor uses two CDNs behind the scenes to speed-up file transfers. One CDN is in the United States and the other in Europe. Large files such as the calculator, tutorials and airfoils database are downloaded from the chosen CDN. Your user data is also stored in the CDN that you selected.

The features available to you are identical regardless of which CDN is selected. This setting is totally unrelated to the Imperial/Metric unit setting. You can also change this selection at anytime through your account settings. But keep in mind that your saved data is not mirrored across networks. Data that was saved in the United States CDN will not be visible if you change the setting to use the Europe CDN.

Picking the ‘wrong’ location will probably make large file downloads (such as running the calculator) go at less than half the speed. If you live outside these two locations, such as Australia or New Zealand, I suspect that the United States CDN will work better for you.

Quick fix: go back to www.rcadvisor.com, logout, and login again. The forums should now know who you are and everything should be working.

Longer explanation: The forums run as an entirely separate application from the rest of the website. They maintain their own user registration information. A module on the main website copies your user registration data between the two systems. If you registered on the main site before May 17, 2008 and use cookies to stay logged in, the forums may not know who you are.

Error code 2032 means that for some reason the calculator could not talk to the server. Unfortunately, the calculator has no way of knowing exactly what the problem was.

Could there be a firewall getting in the way? Is there something unusual about your computer configuration or network connection? Could your Internet connection just have timed out? To avoid firewall issues, the calculator only uses HTTP through port 80.

It can be difficult troubleshooting this error, since there are so many potential causes. If you’re stuck, contact me with your specifics, and I’ll do what I can to help you sort it out.

No, cookie blocking software. The website uses cookies to keep track of who is logged in. The calculator queries the web server for this information.

There might be software running on your computer that is blocking cookies and you may not even know it’s there. This is a known problem with Road Runner customers.

Unfortunately, there are many places where the cookies could be getting blocked. Talking to your ISP might yield some clues.

Slow performance on the calculator is not normal. I’ve gone to a lot of trouble to make sure it always runs quickly. Once the calculator has finished downloading, it runs on your computer just like any other desktop application. The fact that it runs from within your web browser doesn’t matter. It is still running on your computer. The performance of my servers has nothing to do with it.

The power system and airplane charts take the longest to run, but I’ve never seen them take more than one second on my computer. If you don’t care about the real-time charts in the analysis that you are doing, then just select a different chart that won’t need to be updated with every data edit. For example, display a location chart.

Other than that, my advice is the same as for any other situation where a program runs slowly. Install the latest system patches, don’t run applications in the background, reboot, etc.

It is very important for your Internet browser and Flash player to be updated to their latest versions. I have seen many strange screen display problems go away when the Flash player is updated, for example. Remember to restart your web browser after the update.

Click here to see what the calculator is supposed to look like. If it looks different, then something is wrong.

Due to the unpredictability of the Internet, sometimes the calculator doesn’t look quite right even if you have the latest version of the Flash player loaded. It is safe to use the calculator as it is or just refresh the web page to trigger a reload.

I hate having to take sides, but consistently I’ve found that Mozilla Firefox and Apple Safari simply work better than Internet Explorer and Opera.

Questions about the website and technical problems with getting the calculator running on your computer receive free technical support via the Contact Form.

First of all, don’t feel bad. I’ve gone through a lot of trouble making the calculator easy to use, but there’s still a lot of functionality to understand.

Go through all of the tutorials. Go through them more than once if you have to. Read through this FAQ, the Glossary and the Blog. Every data field in the calculator has ToolTipA ToolTip is a small text box that appears when the mouse pointer is hovered over a screen object. The box disappears when the mouse pointer is moved away from the object or after a specified period of time, usually a few seconds. help – just hover your mouse over it for a couple of seconds. There is a lot of information available to help you out!

The best way to learn a tool like this might be to run through a known scenario. Enter the data for a model airplane that you already own. Play with the knobs and look at the different graphs. Pretty soon, it’ll all start making sense.

That would be going outside the scope of the website and your subscription agreement. Please contact me so we can discuss your needs. If I cannot help you, I’ll do my best to find someone that can.

We only require Adobe Flash Player 9. For the best viewing experience, a video resolution of at least 1024x768 and the latest version of Flash Player (www.adobe.com) is strongly recommended. Flash Player runs on Windows, Mac OS X, Linux and Sun Solaris.

The recently released Flash Player 10 has been tested with the calculator and it appears to work fine.

If your monitor is small (1024x768 or 1280x1024), it may help to go into full-screen mode in your web browser. Use the vertical and horizontal scrollbars to center the calculator in your browser window.

A professional aerospace engineering team, using tools that cost many thousands of dollars and spending months on a single design, would be ecstatic if all their simulation results turn out to be within ten percent of the actual performance of the prototype. Your results will probably not be as accurate as theirs.

I never said that the results were inaccurate. They may or may not be, depending mainly on how well the assumptions that the program makes match your model. If it is a very unusual design, the results are likely to be less accurate. But they are almost certainly more accurate than if you just guessed.

There are two ways to effectively use the calculator. One method is to use the results to compare the relative merits of two components. If propeller A looks like a better match for your model than propeller B, it probably is. The other method is to calibrate the results to exactly match your test data. The calculator is still very useful without this extra step, but it is always there as an option.

That is not what I discovered during the early research phase of this project. I found a motor calculator on a vendor website that gives results that are just too good to be true. Another respected website states something along the lines of “we know for a fact that the performance of propeller X is …” and then proceeds to give grossly inaccurate numbers. Another authoritative source assures us that minimum power to fly occurs at stall speed. Wrong!
Through extensive research, I’ve located actual recorded flight data, wind tunnel test results and controlled lab experiments that I’ve used to validate every aspect of the calculator.

No, the scope of RCAdvisor.com is any calculation that involves flying models. I needed the airfoil calculations for the propeller editor. I decided to expose its functionality since it is useful in its own right.
If you know (or can take a good guess at) the airfoil of a given model airplane, by studying the behavior of the airfoil in the virtual wind tunnel you can learn a lot about the flying behavior of the overall model.

If your monitor has square pixels (the vast majority of monitors do), then the plotted coordinates should be accurate.

The vast majority of the airfoils contained in RCAdvisor.com come from the UIUC Airfoil Coordinates Database. These airfoils are covered under the GNU General Public License. This means that they can be used for any purpose as long as you acknowledge the data source and the GNU license.
Some of the data, such as the Norbert Habe (hn) airfoils, are copyrighted. If you intend to build more than three models with the given airfoil, you need permission from the designer.
Like the saying goes, “if in doubt, check it out!”