Mousetrap propelled Airplane

[rlynn]

I wasn't sure as to where this post should of been posted in. But does anyone have any ideas how to build a mousetrap propelled airplane? Any imput will be appreciated.

[ecoli]

define airplane... I suppose you could use a mouse trap to launch objects, but the shape of the object would certainly be a factor.

[Externet]

Hmmmm.... A mousetrap provides a considerable force during a 180º half a revolution short travel; and what you want to move (¿a propeller?) takes comparatively much less force and much longer revolutions...

If you can come up wth a set of gears to use the spring force to multiply the spinning, something could kind of work... briefly.

Like a wind-up toy.

Miguel

[rlynn]

hmmm, well the mouse trap is supposed to propell the airplane (a regular airplane?) and the only use of propulsion is rubber bands, or a propeller and the mousetrap, and the mouse trap has to be connected to the plane at all times.

[Destroid]

Use the Mousetrap to pull a string wrapped around a little thingy connected to some gearing to increase your revs for the propeller is the easiest way i can think of to make the trap power a plane. The plane will need to be pretty robust, mousetraps have quite alot of pull in them.

[ecoli]

How big will the plane be? I have a feeling that the mousetrap would cause aerodynamical problems.

[gcol]

Sneaky, but...

 

first define a mousetrap, simply "a device with the potential to catch mice", however inefficiently. Then build a standard model airplane with a sprung trapdoor in the fuselage, baited. Flying mousetrap solved.

[gcol]

The rubber motor when wound will power the plane, the tension on the rear hook can set and spring the trapdoor.

[Phi for All]

Could the mousetrap arms be extended and used to pull a loose collar down a threaded propeller shaft? Something along these lines only smaller and lighter weight. Carved and waxed balsa wood comes to mind. You could even cut most of the mousetrap away (at least the metal U part) if that's legal.

[lightwave]

Well, you can use a mousetrap to catch a mouse, then train the mouse to crank a propeller and steer an aeroplane.

 

Next inane question please!

[gcol]

Could the mousetrap arms be extended and used to pull a loose collar down a threaded propeller shaft? Something along these lines[/url'] only smaller and lighter weight. Carved and waxed balsa wood comes to mind. You could even cut most of the mousetrap away (at least the metal U part) if that's legal.

 

1. The pitch of the thread is completely wrong for that application, it would need to be far coarser, and of a different profile, square-cut as in a platen press, to reduce friction.

 

2. The weight penalty of a threded device would be unsupportable.

 

3. A small diameter airscrew must turn at several hundred rpm. The length of thread to produce more than a second or two of power run would be several yards at least.

 

So if anyone was at all serious, the rules would have to be very closely examined, and an "out of the box" solution sought, perhaps as my previous suggestion.

[rlynn]

[bUBBLE=How big will the plane be? I have a feeling that the mousetrap would cause aerodynamical problems.][/bUBBLE]

 

I'm not sure about that either. How big would the plane have to be in order for the mouse trap to be strong enough to provide the force of propulsion?

[rlynn]

The only source of propulsion that can be used is rubber bands. propeller and the mousetrap. Motors cant be used.

[gcol]

I will stake all my aeromodelling experience on saying that a standard mousetrap will not supply any useful flying power. The rubber motor will supply the power, the mousetrap will be payload, and the wingspan should be 2.5 to 3 ft. The rules should be specific as to what constitutes a valid flight. Any fool should be able to achieve at least 30secs. with such a settup. Unless the rules specify a maximum weight of rubber, you just beef up the rubber until you achieve your goal.

[adrake]

Reverse catapult. mount the mouse trap on the bottom of the glider. You would need to build something to take the anvil from the moustrap hitting it to launch the glider.

 

Intresting idea, I see a homeschool project for my 11 year old. Drill holes in the mouse trap to lighten it.

 

Great idea. If rubber bands are allowed use them for powering a propeller as well.

[ewmon]

The mousetrap will add significant weight to the airplane, so the designer should place it near the main wings (to maintain fore-and-aft balance), preferably "sideways" (to reduce drag) and underneath (to keep the center of mass below the center of lift) like the sternum of a bird. The "bale" (the part that snaps shut!) would be turned upward in its "loaded" position. To eliminate the relatively heavy weight of gears, attach a strong thread (such as dental floss) to the bale, and wind it around the propeller's metal axle. When the bale is released, it will turn the shaft and propeller (like the pull start on a lawnmower).