Trike Powered Glider

On my farm in NE Ohio I occasionally see one of the local farm boys flying over the back of the property in his trike powered glider. What fun that must be! If I were just a little crazier…

I decided to try modeling this aircraft. The project raised several challenges. First, the wing had to have a stretched fabric feel, with an open bottom. This I did by using only the top half of the skin of the wing, and making a set of ribs to fit. The ribs are transparent, which made for a very nice effect. I also made the ribs in alternating lengths. This gave a “scalloped” shape to the trailing edge, which further enhanced the stretched fabric feel. You can also read the texture from below in a “wrong” reading orientation, which makes it look like the fabric is thin and partly transparent (even though it does not have any transparency).

The second challenge was the control surfaces. I’ve never flown one of these things, but apparently you turn by pushing the control arm left and right. This arm is attached to the entire wing, which makes the wing swing! This was easy to do, and the effect is quite rewarding. However, apparently you also push and pull the control arm for elevator. I had already used the rotation axis assigned to the aileron. DAM only allows us to assign each object to one rotation axis. I need two to make the wing work the way the real ones do. Guess what’s coming in the next version of DAM? Yep. I’ve put in linkable rotation axes, so we can assign two or more rotation controls to a single object :) I plan to release version 2.0 in the second quarter of 2012. The linkable rotation axes will be in that version (along with a lot more!).

We took time to set the flight parameters to make this digital model fly just as we imagine the real trikes do. Apply full throttle and let the model run down the runway. If your controls are set correctly, it will gently lift off on its own, with no elevator input required. There isn’t enough power for a loop, although you can get something resembling inverted flight if you start high enough and push in full down elevator.

Note that we put in some rudder control so you can turn it on the ground. The rudder input also affects the model in flight, which is not something you would have in the real model. For instance, you can snap roll the model by pushing full left rudder and full left aileron at the same time. This could not be done in the real aircraft.

If any of you actually fly one of these things, leave a comment and let us know how close the flight characteristics of the model are to the real thing.

Good Digital Modeling!
Greg

This entry was posted in General Info. Bookmark the permalink.

One Response to Trike Powered Glider

  1. Greg says:

    I forgot to mention that the model maintains altitude at about 1/2 throttle, or about 22 mph. After making the initial turn back torward the pilot position, I find it quite relaxing to settle in at about 200 feet, and use only the throttle (no elevator), to maintain altitude for several fly arounds. It requires watching the altitude, adding a little throttle if we are losing altitude, and removing a little if we are gaining. If you try it you’ll notice that sharp turns need to be avoided.

    Have fun.
    Greg

Leave a Reply

Your email address will not be published.

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>