I crashed Sister Jenny! Finally!

[Tim Wescott]

So, I built this Fancherized Twister in 2013.  I chose to build a Twister, and to leave its wing as designed, because I'd had such good luck with rebuilding my Skyray and my Flight Streak.  I know that a D-tube wing would tend to break badly or not at all, while the Skyray (and Twister) style wing tends to burst the covering but do much less damage to the wing.

And I was crashing All the time in 2013.

So I finished up the Twister, started flying it in competition -- and stopped crashing.  Always, I was straightening out that wing, because the downside to that style of construction is that the covering lends the wing torsional strength, and at least with 'coat, the wing tends to creep out of straight, and needs to be periodically gone over with a heat gun and judicious twisting.

So, today, I'm getting ready for the Shelter in Place Showdown.  For some reason the dang thing is going limp on the lines up high, particularly in the overheads -- I shortened the lines to fit the field I can fly in, and it's affected the trim.

So this was going to be my flight to really pin down what's happening overhead. I did the Hourglass, it went really limp this time, and I managed to recover from the downward leg at what would have been 3" below grade, if only one could fly through dirt.

And -- the wing structure did what it should!  I've just got some diagonal tears in the outer wing, and as far as I can tell there's not even a broken glue joint!  This sucker's getting patched up with shipping tape and Monocoat and I'm going out there again to finish trimming it out.

And it only took seven years of flying before my decision on how to build it justified itself...

[Joe Ed Pederson]

That's my experience as well.  I was given a Monokoted Francherized Twister, a well used one that had had the fuselage broken in half.   I crashed it four more times and out of the four crashes busted the fuselage in half three more times. 

I've cut the wing out of the fuselage and stripped the monokote off the wing.  I expected to find something broken near the outboard tip because the last crash put a pucker in the monokote, but there was no damage at all.  The original builder cut his own ribs ang built the wing on rod jigs and used spruce 1/4" spars.  He didn't add the half ribs that some do.

I'm re-sheeting the center section and plan to build a new Twister around that venerable wing.  I also discovered the original builder installed a 4" bellcrank.   I go back and forth on a standard Twister or Francherized.  I lean more toward a standard Twister.

Some models are called durable.  I've never met one more durable than the Twister.

Joe Ed Pederson
Sir Crash-a-lot
Cuba, MO

[Mike Alimov]

Most people wouldn’t call that a crash, Tim. This is a minor mishap. A crash is when you need a trash bag to clear the circle for the next flyer, and the prospect of repair seems daunting if not insane.
On a different topic, it is surprising to see a LA46 powered Twister lose tension overhead. Something is seriously wrong with the trim. Path her up and figure it out.

[Tim Wescott]

... Something is seriously wrong with the trim...

I know that!  This was like the third or fourth flight after I shortened the lines from about 67' handle to canopy down to 62' handle to canopy.  I've repaired it, moved the leadouts 1/8" forward, and flown again and it's much better.

My intent is to get it at least sensibly trimmed by tomorrow morning and get in my official flights for the Shelter in Place Showdown.

[Tim Wescott]

I forgot to mention that it's a 54 ounce Fancherized Twister -- had it been lighter, I'd probably have a different engine on it.  But it's a Really Thoroughly Painted Fancherized Twister (and it flies pretty darned well for being so porky -- thank you Mikey and Ted).

I have moved the leadouts nearly 1/4" forward and haven't hit diminishing returns.  I suspect that flying it on longer lines was papering over some trim problems.

[Fred Underwood]

Monokote can get brittle after years in the sun.  Then it splits and tears where it would have tolerated the flex.  I unfortunately have experienced that.

You didn't mention laptime or speed.  What did you do to adjust for the line length change?

[Tim Wescott]

Hey Fred:

I let the lap time fall to about 5 seconds, because it seems comfortable there -- I'll probably bring it down more if I keep working on it, but the deadline to get flights in is tomorrow, so I'll probably let it stay there.

Other than that, I've tweaked the flaps (which may just have been the wings creeping a bit since the last time I flew), and changed the leadout position.

Everything else is at least close enough to good that I'm going to fly with it.

[Fred Underwood]

Just curious as that may be part of line tension, as I'm sure you know.  That is a significant change in length and it would seem that a proportional lap time change would be needed to keep speed up and the plane out.  You and Sister J have travelled a lot of miles together, keep her going :-)

[Perry Rose]

Try using the grey level and you will know exactly where your leadouts are. Just moving them is wasting trimming time.
https://www.amazon.com/Johnson-Level-Tool-595-Structo/dp/B00EC8MW5C/ref=sr_1_8?dchild=1&keywords=line+levels&qid=1586695126&sr=8-8