Akom's Tech Ruminations

Various tech outbursts - code and solutions to practical problems

Exceed Pitts S2A first flight (and crash)

Posted by Akom • Saturday, September 6. 2008 • Category: Toys

First flight! Yay! I guess I consider myself good enough after playing with the simulator for a while.

After a little trimming (adjusting the servo pulls with the tiny allen wrench they supply) I got on my runway (a paved road on a park slope) and (with some trepidation) pushed the throttle forward. It took off, with some effort, and flew!

I think it flew with what others have described as a tail-heavy tendency - it seemed like I was always pulling too hard on the elevator - or maybe I was, in the turns, I'm not sure. In any case, all I had to do was push the nose down every so often and it would avoid stalls... which it survived just fine anyway, just taking a small dive and recovering. I circled the area for about 2 minutes, and then just as the plane was getting away from me to the point of "a bit too far", it suddenly disobeyed...

I was making clockwise circles, and the plane suddenly veered left instead, reacting to my input but in unpredictable ways. I was a little too close to losing it in the treetops, so I cut the throttle and let if fall - guiding it down was not going to happen. It fell behind the hill, making me do the "walk of shame" (a run, actually) without knowing what I'll find.

The plane was together (that is, all in one place), except for the landing gear which once again popped out at the sleeve instead of the way it should. The lower wing was snapped in two. And then, after a closer inspection, I figured out what happened. The plane's wings are held together to the vertical stays using little plastic divots, which you turn to release. One of them turned and released in flight (I never found it). The wings effectively separated from each other, causing the ailerons to do basically whatever they wanted - I'm surprised that the plane didn't physically break up in the air. Next time I am taping the divots in place.

I went home and glued the wing, not actually sure whether it can be done. I decided to use a toothpick as a reinforcing "bone" - i inserted one end into the base and the other end into the wing, making the wing stay in place, preventing it from sliding at the glued joint. The RTF kit came with a tube of glue (I am assuming here, there isn't a single marking on the tube), which I used initially - but I may have used too much, as it melted a big chunk of foam away from the joint.

Wing Glued Back Together and taped

I then used Titebond II (a wood glue), which I read would work well, and it worked OK - I don't think it was melting the foam, but it does take forever to dry, especially if you try to use it as a gap filler (which I did). I eventually gave up and filled the gaps with carefully cut pieces of dried-up glue that the shipping box had in a few places. This worked well when combined with Titebond. The wing was now glued back together, though I have no idea how well.

As a finishing touch, I used clear packing tape over the joint, and then, for symmetry - on the other (unbroken) side of the wing too.

Landing gear sleeve that kept popping out of the fuselage.

Since I was using the glue anyway, I also modified the landing gear sleeve: I took a razor to the little tabs that hold the landing gear way too well - and now it can slip out if it needs to. Then I glued the sleeve into the plane body, permanently.

0 Trackbacks

  1. No Trackbacks


Display comments as (Linear | Threaded)
  1. No comments

Add Comment

You can use [geshi lang=lang_name [,ln={y|n}]][/geshi] tags to embed source code snippets.
Enclosing asterisks marks text as bold (*word*), underscore are made via _word_.
Standard emoticons like :-) and ;-) are converted to images.
Markdown format allowed

Submitted comments will be subject to moderation before being displayed.