Not Rocketry: Cox Aeracobra EZ Flier Model Plane Acquired

OK, this is obviously not a model rocket, but I have no idea where to turn for help right now.

The wife has amazed me again, producing this dusty box and informing me that she had bought it for her younger (55 year old) brother... but wanting to know if I have any interest in it.

I've slid the box open, and discovered there's been some leakage of something (fuel?) that has evaporated to become tacky, and stained much of the instructions and cardboard inside. There is what appears to be an empty open can of fuel...and a 1.5 volt square "hobby battery" with leads still connected. There is an instruction sheet that indicates the parts include a top canopy, bottom fuselage, two rubber bands, a drop-in "motor" with propeller, and two or three wheels on wire supports. Some of the stickers are applied, and another sheet that has not. There are also at least two other drop-in paper fliers that advertise a similar RC Robot, and/or a transformers semi-tractor trailer with some form of launch system hidden in it. None of these toys are included, but look like the instructions got shoved into this box. There's the remnant of a price sticker that looks like it was a cut-out sale at Toys R Us, and then listed as a $1 yard sale item too.

I have no experience with this at all. Other than dusting it off and trying to clean it up with a damp rag, I don't know what to do with it. There is some sort of handle with twin strings wrapped around the plastic body...I assume that they are used to guide the plane in a circle around a pivoting operator. But I don't know where to look for fuel for this thing, or if it's safe.

Suggestions?

Very cool - that's a Cox control line plane with what is probably an .049 glow plug engine. If everything is still there and the motor still runs, you can run it using model airplane fuel. Do a search on control line planes and .049 cox engines to get started.

I had the Cox .049 Spitfire and the Cox .049 PT-19 when I was a kid some 50 years ago. Yours was in the same series of control line flyers. Both airplanes survived more than 10 years of flying, crashing, and being patched back together. They were pretty tough plastic planes. Be careful with the manual spring start motors though, I nearly cut my finger off starting the Spitfire once. You should be able to find the instructions on line. Happy flying!

I had a P-51, a WEN-MAC Hover craft and a few others. No kidding about that spring starter, I resorted to ''Old School'' flip start with mine. I ended up on a glow engine forum site one time for some reason and found that glow fuel now required hazmat shipping. That was a few years ago so I could be remembering wrong. But there were mix your own formulas that are better and not hazmat to ship the supplies needed on the site. Who knows, it may be possible to convert it to RC with todays components... Then again I could be wrong.

Cox control line jobs bring back fond memories of falling down dizzy.

Good times.

o1d_dude said:

Cox control line jobs bring back fond memories of falling down dizzy.

Good times.

Click to expand...

Combat with streamers was the best of summer days!
Kirk- if you want to know any more, pm me and I'll do a data dump about the care and feeding of this beast. Fuel, batteries and new glow plugs are still available. You may want to replace the lines too!

o1d_dude said:

Cox control line jobs bring back fond memories of falling down dizzy.

Good times.

Click to expand...

Somehow, I suspect finding other ways of making yourself dizzy and falling down has not been a problem for most of us. LOL!
(Truthfully, I did wonder about this as a hazard...)

Stan said:

Both airplanes survived more than 10 years of flying, crashing, and being patched back together. They were pretty tough plastic planes. Be careful with the manual spring start motors though, I nearly cut my finger off starting the Spitfire once. Happy flying!

Click to expand...

+2 On the spring starter. Still have a scar on my left thumb from the first start of the .049 on a P26 Fighter when I was 11-y/o.

Here is a photo of another "control" line model that used 1/16" steel cable and could go 215mph from the 1950's. Suzuki/Edwards F94C Starfire with Tiger Jet engine. ( Great Way to get dizzier even faster...)


Mike

Kirk- check your PM's.

OK, after some help from others, we have determined that the kit is virtually complete. It is missing the glow plug WRENCH, but the glow plug itself is intact and servicable. We have no nitro-gas, but can buy a quart for $30 or so. There is a connecting rod for the rear allerons in place.
and I need a 1.5 volt battery. The motor is currently been sprayed with WD-40 and the cylinder head was removed. The needle value was worked free, and it looks like it's usable.

However, if a new .049 COX engine is needed, I'll have to go onto the collector's market to find it. And there appears (at least on Ebay) to be a variety of names or variations on the .049 Glow Plug motor. Can anyone assist me to tell me if it's a "Baby-bee" or some other variation that is needed for the P-39 Airacobra model? I have no immediate need, but as these wear out, and I've been told to let this one "wear in" on a test model bench, I may need some insurance.

Also, I've been told the propeller is intact, though the thin yellow plastic nosecone is not secure. But I've been warned to check that the propeller is not on backwards! (Is that possible?) Also, someone suggested using a sharpee marker to turn the prop about when starting to save one's fingers.... which I suppose I can understand.

How long do these things fly during any one session? The reserve tank looks intact and servicable as is.

If the glow plug works, the needle valve turns and isn't corroded and the crank shaft turns (and the piston moves freely), you should be good. There isn't much else to those .049 engines. You can see the piston by leaving off the glow plug and engine cover and turning the propellor. If it moves up and down on there and doesn't bind at any point, you're good there. Then, with the glow plug still off the motor, hook it up to a battery - if it is good it will glow bright orange after a few seconds. If I remember correctly (it's been a while), you need a lot of current to make that thing glow - four D cells wired in parallel should be plenty. Once everything is free and moving like it should, put the motor back together. Now when you turn it you should get some resistance at certain points - that means you are getting compression. If not, your piston is shot (not too likely).

If it passes these tests, it is time to test fire the engine. If possible, remove the engine from the plane and mount to a large block of wood clamped in a bench vise so it doesn't go anywhere. Put the prop on and fuel it up. If it is loose, you don't need the prop spinner unless it actually holds on the prop - if that is the case there WILL be a way to tighten it. Fill the fuel tank, hook the glow plug to a battery and try to start it. It will take several trys, but if and when it does start, start timing - the test run will tell you how long a tank of fuel will last (my guess is between 5 and 10 minutes). You can adjust the speed of the motor by turning the needle valve in and out. Also, check the air flow from the prop - if it is blowing out like a fan, you have it on backwards. It probably won't hurt to let it run that way, but on the off chance the engine needs the prop wash to keep itself cool, shut it down (closing the needle valve all the way should do it), remount the prop the correct way, refill the fuel tank and start it again. Once you know how long a tank of fuel lasts, you are ready to put the motor back in the plane and get it ready for its first flight.

When trying to start any engine, use a "chicken stick" to flick the prop. It will save your fingers. A 1/4 inch dowel about a foot long will work well.