krisI.925
05-02-2002, 03:08 PM
Shortening the fuse on my Lite Stik
I was wondering what would the effects be if i shortened the fuse on my Lite stik about 3 inches or so. I know it would make it more manuverable but what would it do to stability.
Also what is a good plane that is pretty durable and some what easy to fly. I want to spend more time flying and less time fixing. I was thinking of the tiger moth but i want some more opinions.
Richard Miller
05-02-2002, 08:45 PM
KrisI,
This gets you the area of masses and their moment arms. The effectiveness of the tail moment arm, TMA, is a function of the distance from the aircraft C.G. to the point on the stabilizer surface where lift, up or down, is concentrated.
Thing is, that moment arm, as they all are, is ruled by an exponent, the square of the length. So if you went from, say, 12", down to 9", you'd have 81 of 144 units of effectiveness left.
That's just math, however. To see what's enough, and what's not, you'll probably have to make the experiment, but knowing about the exponent may help when you see what happens.
-Richard
Dave Robelen
05-02-2002, 09:45 PM
Hi KrisI,
Richard is right on in the math part. When you go to the Litestik specifically, the tail is both larger and farther back than really necessary to allow for a wide range of balance points. When you shorten the tail, the model will be quicker in pitch, but it also will be more sensitive to balance changes.
The other factor is that you will be moving the vertical tail forward, and that is not oversize. If your "stik" shows a tendency to rock from side-side, or tuck it's nose in turns, you will need to make a larger tail surface. I would add area to both the fin and rudder if it comes to that. Experiment, have fun, and let us know how you make out.
Regards, Dave