Small mods to an Balsa USA Enforcer...
 

I am thinking about doing some simple mods to a Balsa USA Enforcer. I want to add some small canards and LEX to the plane. The three pictures show roughly what I would like to do. Total lifting area added in front of the CG is 25 square inches. I am curious how much this will affect the CG considering how much wing (1000 square inches) is behind this small mod. Any suggestions out there? Does anybody think that the CG would be greatly affected (no more than 1/4 inch movement at most)? I would like some opinions or suggestions to do it or not to do it and what you think the effects to the CG might be. The last picture is not exactly to scale with the overhead one as far as in exact placement. If anybody needs any information to make an educated or informed guess, let me know.

Thanks in advance!

RE: Small mods to an Balsa USA Enforcer...
 

I think you would be safe, but to be sure I'd put some lead in the nose to get the Cg 1/2' forward for the first flight.

The two, LEX and small canards, seem to be doing the same thing i.e. generating a vortex to increase lift at slow speed, I'd go with one or the other, my choice would me the LEX. If you are moving the canards I think they are so small that they would cause more problems than they are worth.

RE: Small mods to an Balsa USA Enforcer...
 

Hi Soarrich,

Thanks for the reply! The addition of the LEX and canards are more for appearance than functionality. The canards would be fixed (0° and located along the center line on the plans). Part of me is thinking to either make the canards larger and functional ( I believe that I can calculate the new CG based on whatever size I make the canards) or making a larger LEX and have no canards. The only thing is I only have a basic understanding / idea of how to add the LEX but do not know how to calculate the CG properly with the LEX added. I know that it will extend the root chord length but it will not extend all the way to the tip chord. It will not go much more past the 2nd rib from the side of the fuselage. If you have any more suggestions, I would love to hear them!

RE: Small mods to an Balsa USA Enforcer...
 

From what I've seen canards are very prone to damage. I Binged photos of Balsa USA Enforcer and quite a few have small canards.


If you make them functional you'll have to treat the plane as a canard not a delta. With a delta as you pull back the elevators become less and less effective until you reach Max Alfa, the canard should stall first never letting you pull the really high Alfa.

I have a EDF unit I was thinking of putting in a larger Polaris XL, basically your plane, and getting rid of it's "T" tail. With no stab it would become a delta which would be hard to ROW, so I was thinking canards also, but to get the most out of them you'll have to reverse the elevator functions of the elverons. If you reverse the elevator and pull up you increase lift on both the canard and the delta wing, it's more complicated, but you wind up with a wide speed range. RCM Cobra from ~'75 used this function, now it would be easy to do using computer radios.


I like the large LEX, think SR-71.

The cool thing about what you are doing is I don't think you can go wrong if you make it too nose heavy. You won't be able to rotate easily if it's too nose heavy so you just keep taking nose weight out until it rotates.

RE: Small mods to an Balsa USA Enforcer...
 

Thanks Soar,

You are correct in that if I add a larger canard, then it is no longer a true delta. I have a online calculator that will allow me to calculate the CG for a canard. It takes various measurements from the canard and wing (which the delta wing would be treated no differently). The main reason I want to add one of the two (or both) is that I do not like how the front of the wing enters into the fuselage along with the stubby nose of the Enforcer. The canards are cool looking (and can be functional if I choose) but I really like the idea of a more gentle blending of the wing into the fuselage (like the FA-18 Hornet). Also, what I want to add is actually called a leading edge root extension (again, like the FA-18 Hornet). Actually, I could just blend the canard and LERX together such as is seen in the SU-27 Flanker or SU-34 Fullback. I guess I could make several gliders with different configuration of the two and see how they affect the CG. Again, thanks for your comments!

Happy flying and soft landings!

RE: Small mods to an Balsa USA Enforcer...
 

guys here is a few shots of enforcers I have modified, 2 of them are EDF the unfinished one I enlarged the plans 30%

RE: Small mods to an Balsa USA Enforcer...
 

Man don't leave us hanging, tell us more about these cool planes.

RE: Small mods to an Balsa USA Enforcer...
 

anyone want more info or photos email me to I am having problems adding more photos
Bill heersema

[email protected]