I have this plane that a fellow clubmember gave me, and I want to know what it is. I believe it to be a Herr Little Extra but I have never seen one before so I can't be certain.
The engine is also unidentified. This model was owned by a guy in england, so I believe it is of british design
On one side it says AP and on the other side it says 9. It has a throttle carb on it, with two needly valves. It has a muffler attached to it, a interesting design that sits right behind the engine (Rear exhaust???) and is not the shape of a modern muffler.

Update I have confirmed it to be a herr little extra, but still unknown on the engine????

The engine is an AP. .09 or .15. What size prop?

Judging by the head it is an AP 09 engine.

AP 09 would make sese. It says AP one one side, 9 on the other.

How long have these things been around? Mine seems to be an older specimen and is gommed up a bit. How should I clean it?

Well, if a plane is really filthy with grease and dirt, I will take rubbing alcahol and cotton balls and clean it with that, but I only do that when I need it, because it smells bad. I use 409 to clean up from everyday flying.

Originally Posted by kylerdinger

Well, if a plane is really filthy with grease and dirt, I will take rubbing alcahol and cotton balls and clean it with that, but I only do that when I need it, because it smells bad. I use 409 to clean up from everyday flying.

Sorry I didn't make myself clear, I mean the engine. I have had to clean a few planes here and there

The inside will clean itself while running. For the outside, just leave it as it is, a little patina just shows that it has lived.

Originally Posted by surfer_kris

The inside will clean itself while running. For the outside, just leave it as it is, a little patina just shows that it has lived.

The way it is now, It will never run. It is incredibly stiff, to stiff to even attempt starting.
And, what kind of fuel should I use? I have never had anything smaller than a .40 so I have no clue

Fead it some glow fuel and turn it over, that's usually enough. If not then take it appart and clean in glow fuel.
These engines are no different from a .40 engine, any fuel with about 20% oil and 5-10% nitro will do.

Originally Posted by Waffleman

The way it is now, It will never run. It is incredibly stiff, to stiff to even attempt starting. And, what kind of fuel should I use? I have never had anything smaller than a .40 so I have no clue

This is how I do it. YMMV. I disassemble it and soak it in a volatile solvent like acetone. Since I am out of acetone, I used automotive lacquer thinner.

I am careful during disassembly to not destroy any gaskets so I can reuse them. Otherwise, I end up replacing or manufacturing my own. Recently I used Permatex Ultra Gray RTV caulk to replace an OS Max .10 back plate gasket. Not saying to do that, I'm experimenting the gasketless solutions.

Don't soak the gaskets and above all the neoprene O-rings om solvent, good way to damage or destroy them.

Wear gloves. Use something like an old toothbrush to remove grime after softened. Fine steel wool or Scotchbrite pad will help to clean the upper combustion chamber. Go easy on the aluminum parts.

I compressed air if available to blow out the solvent from parts. If not available, then I make sure the crud particles are washed out by swishing in solvent before removing. After drying and during reassembly, I put a drop or two on all bearing surfaces and wipe the cylinder bore with motor oil or 3-in-1.

Your .40 sized fuel should be okay if you have some nitro content. I found this recommendation in the AP Wasp .061 Instructions, which seems to be good advice on having at least some Castor oil content in the fuel:

AP Instructions: Note: We do not recommend using fuels that contain only synthetic lubricants. Synthetic lubricants have a much lower flash point than Castor Oil lubricants. The Flash point is the point at which the lubricant suspended in the fuel begins to actually burn and loses it’s lubricating qualities. Using fuels containing a blend of Castor Oil and synthetic lubricants results in an engine that runs cooler and lasts longer. One lean run using a fuel containing only synthetic lubricants can cause severe engine wear and eventual failure in a short period of time. Using fuels with a Castor Oil and synthetic blend of lubricants greatly reduces this chance. Please also keep in mind that the higher percentage of nitro in the fuel will produce more power, yet it will also cause the engine to run hotter and to wear more quickly. This is just one more reason to use a fuel containing a Castor Oil and synthetic lubricant blend.

I got it freed up by putting some fuel through it and letting it sit for a few minutes. Still has good compression.
My fuel is 10% nitro with a 18% oil blend of castor and synthetic. Sounds like the perfect fuel for it, So i'm going to try to start it up today.

It is a nice running motor, and a good simple design. You will likely find it a good match for that plane.

I got it fired up today. Needed 5 clicks richer and it was singinn dixie