What would be the advantage of a certain type of "engine" (i.e. rubber band, RC, Gas) over another?

Well rubber would be a free flight and and glow would be RC

i know gas engines run a lot longer than a Nitro engine...

and a rubber band engine is just a childs toy...

rubber band = freeflight, "childs play".

Electric = quiet, but short flight times.

Glo = louder, but moderate flight times.

Gas = similar to glo, but more economical granted you have a gas engine.

sounds like a homework question to me.

There are a few rubber band powered RC models out there, belive it or not. Small indoor jobbies done by guys just because they can and it sounded like a good idea at the time. (some are reported to have rather decent flight times as well). But in general, it's not a practical power source for RC.

Electrics are quiet and slime-free. Most common are the smaller park flyer sizes. These have low power output and the planes don't always handle winds very well. However, if you spend enough money, you can do anything with an electric that you can do with glow(nitro) or gas. The big advantage to the small electrics is that they can be safely flown in a park or large backyard.

Glow (aka nitro) has the hightest power-to-weight ratio out there. Glow engines are actually fairly easy to get working right once you get past the initial learning curve. But they are loud, and make a mess on your airplane. The fuel is also expensive, at $15-25 per gallon, depending.

Gasoline is cheaper than glow, so gas engines make sense in the larger sizes where fuel consumption is rather high. Also, many (but not all) of the large gas engines can trace design influcence back to small gas powered devices like leaf blowers and weedwackers. So, for the size, they are cheaper than Glow. But they don't produce as much power for the same displacement as Glow, and you have to deal with a spark ignition system.

Hi,

The Dumas aircraft people make a rubber band powered airplane w/ a 30” wingspan. The Beaver is the name of the airplane.

I want to put an electric motor in it, instead of the rubber band. What electric motor and battery size should I put in the plane (be very specific please).

First time forum writer, so please be gentle.

Dumas? I thought they made submarines.

You'd do a lot better with that question in the electric forum, or over on ezone/rcgroups.

This will have nothing to do with the original question, but I could no longer ignore a couple of the above posts. I've been a modeler since early childhood, over 50 years, and have built lots of models. Flew my first R/C in 1960. Over the years, I've found that rubber power free flight to be the most challenging aspect of model aviation. I think almost anyone can buy an arf or rtf trainer and learn to fly it in a weekend or two, but if you will ever watch a competitive rubber F/F clawing for altitude then transition into a long, flat glide, you might get hooked. Jim

I wouldn't call rubber power "child's play" the guys who do that are technically ahead of a lot of us!

I too was going to post a reply to try and educate those "rubber power = child's play" posters. I've been in RC for about 8 years now, and have quite a bit of experience building, but I sincerely doubt that I could get a free flight rubber powered plane to perform the way experienced free-flighters do.

I would advise these guys to read a couple of free flight articles in the AMA magazine. The indoor free flight folks can get well over 20 minute flights out of their planes. Could you get an airplane powered by rubber to fly in a large gym for 20 minutes straight?? And the outdoor free flight flyers very often get "out of sight" flights.
Dennis-