Flight report:
I was able to get in 8 flights today of varrying lengths. I had previously disassembled the TD, cleaned everything up, replaced the venturi, and reset the piston. Then I ran it 3 runs on the stand. So I assumed it would run just fine on the plane.
I know, now that you've stopped laughing, I'll continue. Just didn't run consistant, some runs were blazing, others were fine, then quit, etc... I looked at all the usual culprits, cut a new piece of fuel line a smidge longer for the needle, added a head shim, subracted a head shim, changed the glow plug. Finally when I was just about to take Bill Attwood's name in vain (I know, blasphemy) I found the issue. As I was getting set to launch for the 9th flight I saw the dirt specs in the fuel line headed for the NVA. Tank was clean when I put it together so it seems my Sullivan fuel bulb had bit the dust after only 10 years and was breaking up inside. Go figure. But I did get a lot of flights in so here goes.
The Launch:
The CG is set well aft compared to a "sport" model so if you give it a normal 1/2a launch it goes a bit nose high and tail heavy like one of the Kardashians trying to swim. But that is short lived and it climbs out quickly. Once at speed the tail heaviness disappears so I am thinking I am close for this type. I played with the CG but it flies fastest with the cg aft. I found if you toss it exactly straight out on the launch it's a piece of cake. If you do get a slow flight (Like if you were stupid enough to use an old fuel bulb and the dirt kept clogging the nva) it will snap out of a tight loop. On a normal run loops are HUGE and fast (a relative term here in 020 speak).
On the subject of CG adjustments, this turned out to be quite simple and I included a picture. I would like to say the idea evolved from longs hours spent engineering it, performing the calculations, and running through a few computer models, but I think the folks at Boeing and Grumman refer to it as "Happenstance" engineering. As I said ealier I had cut through the rear bulkhead to slide the battery back. For some weird reason I had patience that day and cut it out slowly and kept checking the clearance. The end result was a nice snug fit where it kind of snaps into place in between the cells on the 260mah nmh battery. So to change the CG you just snap it forward one cell or back one and presto! CG adjusted at the field. I know all the pattern guys are jelouse just reading this and you'll probably see a lot of planes set up this way at the NATS this year. But again, I digress....
Control throws:
I had set the throws again using the time honored "Looks about right" technique mentioned earlier in the thread. This did not work out as well as my neat CG adjuster. The CORRECT throws are 1/16" up and down on the ailerons and 1/8" on the elevator. This will still give you about 2 rolls per second. Turns out I had A LOT more than I needed. So the first flight was a bit white knuckled and wouldn't you know that was one of the runs that ran blazing all the way to the end of the tank.
Landings:
This is pretty much a non-event and it's close to the old GLHs. If you keep the speed up and then flare its smooth as silk. If you try and streatch out the glide like a sport model its more like a controlled stall, just kind of sinks like a power on stall in a cub. But due to the swept wing, even with the aft CG it doesn't drop a wing or get nasty.
Airframe:
Turns out it's quite a bit sturdier than it looks. One landing in a 5' mullberry bush and another time I snapped out of a loop and flew full speed into another bush without a scratch. So it's probably over built and leaves lots of room for those of you who chase the Goddess of Lightness.
After getting the trim settings and throws set, it is a blast to fly so far. I'm going to ball park the speed right now at somewhere in the 40-45mph range. It seems like it's almost twice as fast as the wee stick with the pee wee, and it might be as the stick is fat and slow and the pee wee doesn't realy unload in the air, it just kind of zips around being held back by the fat wing. You can put a Nelson on a cub with a 9X8 prop but you're really not going to go any faster. The TD does unload quite a bit in the air with this airframe, so I think there is lots of room to improve. I am thinking that it's possible to easily get past the 50mph mark on a stock TD just using the right prop. 60-70 is probably going to take some motor work but I think the plane won't be the limiting factor. In any event, it's a lot more fun to fly than the stick and gives the impression of flying much faster due to the diminutive size. Plus it doesn't seem to even notice a 5-10 mph breeze.