Firecracker outboard flap

I'm only new to building good size stunt ships as I've always built TR,Combat,15 size stunt models + sports models over the years,but I'm completely stumped to the detail drawned on the extreme outer end of the outboard flap on Brian Eather's design Firecracker. The way I see it is that a square piece is cut out of the flap and a couple of pieces of 3mm balsa are fitted like a slat arrangement. So could one of you knowledgeable stunt guys out there please let me know what it is and how it works,it will be appreciated very much.
Thanks Betsy.

Hi Betsy,
It's a drag producing device - the idea is that when the flap is faired (neutral), no extra drag. When the flap is deflected it produces a little extra drag to yaw the nose of the model out. More deflection, more drag.Doesn't seem to produce asymmetric lift though.

I'm not sure that Brian still uses it, some of his newer models dont use it. I tried to phone him, but he was out, I'll check again thisPM (Aussie time) & get back to you. I'll try to find his email & you can find out from the horses mouth.
Cheers,
Dave Simons

Thanks Dave,
That makes good sense,amazing how simple something is when its explained to you,thanks again Dave.
Regards Betsy.

Dave is quite correct and Brian hasn't used this idea for I would think ten+ years. The slats don't seem to make much difference and they get clogged up with flies in summer.

LAST EDITED ON Nov-08-03 AT 06:55 AM (CST)
 
What I find surprising Tim is that Paul Turner has persisted with the idea. His current WindWiper has large slots cut with part of them covered over again with clear plastic. I cannot understanding why anyone would want to deliberately create yaw movement when we do our best to eliminate it. I have them on Doug Harlow's latest model too, and have covered them over, with no detectable difference.

Although I saw that idea used 40 years ago, I'm sure Brian's reason was in line with his desire to fly as slow as possible on the longest possible lines, hence poor tension at times. After his question earlier this year about line length, I wonder if his desire has changed.

Ken et al

I discussed this with Paul several years ago and he had the entire slat thingy covered with clear tape top and bottom. He said at the time that it was not needed on that model.

I'm pretty sure that he used the same model at the NSW Championships in June and I thought the slats were still all covered with clear tape.

Brian has been working with 4-strokes a fair bit this year but I have not seen slats on any of his recent models. Tim is in touch with Brian more that I am, so I would take the Rev Tim's message as Gospel truth. Sorry about that, I could not resist.