Black horse super air C of G needed
 

hi..

after a few years away from model aircraft i decided to get back into it, having found a half finished super air in my loft,, trouble is i have lost the origional manual and need to get an idear of where its Cof G should be, so if anyone has got one that knows please help...
have tried looking online but can not find any manuals listed for this plane
many thanks
keith

RE: Black horse super air C of G needed
 

Keith first I have no idea of what this airplane is but figuring out what a good CG position is a simple task but first a couple of questions about your airplane. First is this some sort of trainer or a low wing plane.

Now the most import question is what is the configuration of the wing, is it a rectangular board wing or a tapered wing, eliptical etc?

If you can describe the answer to these questions I can explain the very simple method called midspan averaging that requires no computer and can resolve these question easily and will be useful for years and all your models if you desire.

John

RE: Black horse super air C of G needed
 

<a href="http://www.moormodels.co.uk/acatalog/Black_Horse.html">

http://www.moormodels.co.uk/acatalog/Black_Horse.html</a>


john.

here is a link to a picture they still sell them.

its not a trainer but will use it as an intermediate after my wot4 by chriss foss.

hope this answers the questions you raised.

have found another link on a different sit that lists 2 different measurements one as 100mm and another from same model 7 years previous at 125mm so will be interested to see how your formula works out on mine.

many thanks...

have also now discouvered that the installed 138 df reciever has also died ,, twitches when switched on but no movement of the survo's. ah well new reciever too :-/

keith

RE: Black horse super air C of G needed
 

Thats a converted low wing trainer similar to a CG Tiger etc. I would suggest 1/3rd distance from leading edge at the fuselage as a good starting point. Also, cross-check to make sure this is about on the spar (or the line at which the leading edge sheeting ends)

Ameyam

RE: Black horse super air C of G needed
 

OK Keith, excellent I would be pleased to divulge the simple method. Just got back from the field and had some pleasent flights with my Wee Waco and lot of good BS around the burn barrel :D

OK first for that type of airplane and in reality the majority of airplanes I test. I always start out at 25% MAC not one third. That Mac stands for mean aerodynamic cord, actually just the average cord from the leading edge of the wing to the trailing edge of the wing.

Now how do we find that average cord? well thats easy with a board wing with equal cord its just the measurement from front to back anywhere along the wing. The confusion starts though when you have a single taper wing (just leading edge) as yours or a double taper wing, heck even an eliptical wing.

Its easy with these wing type too, simply measure out half way from the fuselage to the wingtip. At this point measure the cord. Divide this measurement by four and measure this back from the leading edge out there at this half way point. This point is going to be your target CG and you only need to use a straight line from this 25% point or quarter cord out there inward to the fuselage side and thats all you need to do. This is your target CG and what you want to balance to.

This will give you an absolutely safe starting point every time with the majority of model types you will ever fly and you can apply this method in just a few minutes. I use this method with all of my aircraft every time particularly so when as often happens many manuals are wrong and this happens far to often.

John

RE: Black horse super air C of G needed
 

John.

laid out the plane today and followed your instructions, and the C of G worked out at 105mm from the leading edge,, which goes with what i had found on another site re thw manufacturers recomendations

thats a great and easy way of working it out.

many thanks

keith