New Member with Question

[matttornado]

Hi.

I'm new to this forum but built many balsa kits as a kid. Man, I wish we had the internet back in the late 70s/80s!
So I'm starting this hobby back up again this fall/winter with my son so I have a question about gas / Motor Free flight:

Does the gas power free flight run on just a few seconds worth of fuel?
I learned that timers can be used with electric motors....

If anyone has any info or knows of any links pertaining to how Free Flight works, types of engines, and how to install them, that would be fantastic! If i remember correctly, the Guillow's plans suggest engine size and give some instruction, is that correct? It's been so long.....

Oh and will a gas powered propeller cut fingers off? Sorry had to ask!

Matt

[David Lewis]

Gas free flight requires a large flying field. You usually use a partial tank so the airplane doesn't get too high and fly away. You will get noise complaints unless you are out in the country. The engines suggested in the plans are much too powerful, in my opinion, for these small planes. They were the smallest engines available when the models were designed.

The longer the motor run, the higher the airplane gets, and the bigger your flying field will need to be, so electric free flight uses a timer to shut off the motor. If the prop on a Cox .020 (cubic inch displacement) hits your fingers, it will hurt, but that's about it.

[matttornado]

Thanks! How does one decide what size motor to use? wingspan length?
Sorry for the beginner questions

[David Lewis]

You would like thrust equal to 40% to 50% of gross take off weight.
There is a motor thrust table:
http://www.homefly.com/reference/Electric%20motors.htm

[Billy Mc]

... If the prop on a Cox .020 (cubic inch displacement) hits your fingers, it will hurt, but that's about it.

I don't know anything about the .020, but those .049s back in the 70s would give you a nasty gash.

[davidchoate]

RC Groups Forum has a lot of info. I was loke You 5yrs ago and now I am a little more knowledgable. Co2 motors were My favorite, but now they are hard to find.