PM-Bee (oz4226)


PM-Bee (oz4226) by Howard McEntee 1972 - plan thumbnail

About this Plan

PM-Bee. Sport model for CO2 power and either free flight or radio control.

Quote: "Whether you consider yourself a typical, experienced model builder, or are an Ace at local model plane meets, you might like to add this little engine-driven plane to your squadron.

You can fly it almost anywhere - it's powerplant is scarcely louder than a bee. Fueling is a simple, odorless operation. There is no smoke problem. It is sophisticated, but fairly simple to build.

Carbon dioxide gas (CO2) is the fuel. Under pressure, as it is in the cannisters you buy - the gas is a liquid, which means enough can be carried in a small tank for long flights. The liquid vaporizes as it expands to drive the engine. The powerplant is similar to a steam propulsion unit in that the the tiny CO2 tank in the plane acts as a boiler, and the surrounding air as the fire.

Under high pressure in the tank, the liquid CO2 travels through an exposed coil in which it is warmed to outside temperature. When it reaches the engine, it is a high pressure gas. A tiny ball valve in the cylinder head, opened when the piston reaches the top of its stroke, meters the gas into the cylinder as needed.

This little plane, which we've named the PM-Bee, can be built as a free-flight model or as a radio-controlled Flier. Very lightweight commercial equipment is now available to make R/C flying of such tiny planes quite practical.

While of simple construction, the Bee is not a first project for beginners: its delicate balance acquires some skill to achieve. But for the powerplant, cost of materials is low.

Keeping weight down is a must to obtain best flying qualities. Pick all wood carefully. Use a minimum of cement (just enough for firm joints) and as little dope on the com-pleted plane as necessary.

The fuselage sides and doublers (the latter run forward from station E to the nose) are of soft 1/32 sheet; the heavier outline on the fuselage side view shows exact shape to cut the sides. The doublers are the same, but taper off between stations D and E..."

Supplementary file notes

Article pages, text and pics.


Did we get something wrong with these details about this plan (especially the datafile)? That happens sometimes. You can help us fix it.
Add a correction

PM-Bee (oz4226) by Howard McEntee 1972 - model pic


PM-Bee (oz4226) by Howard McEntee 1972 - pic 003.jpg

Do you have a photo you'd like to submit for this page? Then email

User comments

No comments yet for this plan. Got something to say about this one?
Add a comment



Download File(s):


* Credit field

The Credit field in the Outerzone database is designed to recognise and credit the hard work done in scanning and digitally cleaning these vintage and old timer model aircraft plans to get them into a usable format. Currently, it is also used to credit people simply for uploading the plan to a forum on the internet. Which is not quite the same thing. This will change soon. Probably.


This model plan (like all plans on Outerzone) is supposedly scaled correctly and supposedly will print out nicely at the right size. But that doesn't always happen. If you are about to start building a model plane using this free plan, you are strongly advised to check the scaling very, very carefully before cutting any balsa wood.


Terms of Use

© Outerzone, 2011-2024.

All content is free to download for personal use.

For non-personal use and/or publication: plans, photos, excerpts, links etc may be used, provided that full and clear credit is given to Outerzone with appropriate and specific direction to the original content i.e. a direct hyperlink back to the Outerzone source page.

Unauthorized use and/or duplication of this material without express and written permission from this site's owner is strictly prohibited. If we discover that content is being stolen, we will consider filing a formal DMCA notice.