IAD

Another four transformation cycles, still no visible progression of the mark, and no others have shown up. I will say that from a design standpoint, they could have put some pretty good-sized fillets behind the body/wing-support hinge, without affecting the transformation. This would eliminate the stress riser created by the sharp edge. Actually, I might do that with a spot of epoxy, or CA + glass microballons. ~Luke

The fourth picture looks much much worse than it is. The flash reflected a bit, but it's not cracked, and I've cycled it again, and it doesn't look any different. The plastic is reasonably thick at each stress point, so... I figure I'll just keep cycling, and keep track of any changes. If something breaks, I'll replace it with milled aluminum, or something. ~Luke

I got one, and... Wow, this is nice... So big, and very mean looking! It can even do the periscope firing pose! Overall, I'm very impressed, there are a few joints I'm going to tighten up, but aside from that, it seems very well designed. I for one am not having much trouble with the composite weapon/fuel pods, they seem to stay quite well. Also, the wings fold equally, no double-right hinge, as far as I can see. I've done two complete transformation cycles, and so far, everything's still in one piece, though on close inspection, I did find a couple stress marks. I think they're minor, but for the record, one is where the metal wing support connects to the main body, and the others are around the fin pivots (both sides). I didn't apply abnormal force to any of these joints, and as I cycle the parts, they don't seem to be getting worse, so I'm thinking that this is just the result of assembly stresses. (The camera flash makes them look much worse than they are, by the way.) Does anyone else have marks like this? ~Luke

David brings up a good point, regarding paddle shape. From my experience, the SV-51's paddle shape is pretty bad, in terms of vectoring efficiency. The paddles are very narrow, so they tend to 'spill' air rather badly, and the angles on the vectoring faces cause the exhaust to flow outwards, towards the tip of each paddle. This effectively makes the exhaust duct exit diameter larger, which reduces the efflux velocity. Of course, my experience is with a ducted fan, and not a turbine, but still, short, flat-inner-surface paddles (like those on the X-31, F-15S ACTIVE, F-22, as well as the YF-21 and VF-22.) seem to be more effective, and result in smaller thrust losses. ~Luke

The Kentucky Fried Movie (1977). I named it! Wait, was this a closed-book exam? ~Luke

Maybe OT, but the WWII V2 ballastic missile had a four-way spade thrust-vector system, as I recall. Definitely, the X-31 beat the YF-21, though. ~Luke

Wouldn't that be "SV-51 Gamma"? Nu looks like a V, while Gamma looks like like a 'Y', or 'r'. ~Luke

Looks fantastic! Thanks for the pictures, Swoosh! The wings go into gull configuration any time the boosters are lit, but the rest of the time, the wings are straight, even with the boosters mounted. ~Luke

Yeah, the -21 looks sort of stubby, from certain angles. (Top, mainly.) In other orientations (like the one in the photo above) it looks great. (In that photo, I'd say the -21 is better-looking.) The -19 looks good from any angle though. ~Luke

Ooh, yeah! M0 monster, in 1/60th! What would that be, about 3' long, right? ~Luke

Yep, the SV is a 'viable' candidate for VTOL GERWALK, in theory. (Three 'lift points', the two legs, plus the lift fan.) Very expensive, and not 100% guaranteed to work (relatively slow fan response time could make stability hard to achieve) but, not altogether impossible, either. Just impossible with 40 mm fans. Probably would need at least 90mm fans, which means an 81" long model. (BIG!) ~Luke

MechTech: Thanks! I'm sure Sean will post videos. They'll be great. Rotorhead: It uses 40mm ducted fans. It's a heavily upgraded version of the one I built, and flies great on the fans. "We don't need no stink'n pusher props!" ~Luke

Is the YF-21 bigger? The Compendium says the SV is 22.77m long, whereas the YF-21 is "only" 19.62m. ~Luke

So, is the Aug. 20th release date still solid, or is it "end of August" now? Because the 20th is really close. (Then again, end of Aug. is pretty close too, so...) ~Luke

Ok guys... I couldn't resist. Here's my guess as to what the side view will look like. I arrived at it using a very scientific method... I traced the battroid CAD image into my CAD software, reoriented all the parts until they fit together, and then filled in the blanks. I then aligned the now-assembled side-view with the top-view, and tweaked until it all lined up correctly, length-wise. It aligned with the top view pretty much at every major point, which is promising. Everything's color-coded, green is 100% authentic trace-from-image, while red is "just guessing." I've got to say, it looks pretty sleek. If it looks this good, that's going to be one incredible YF-21. I do have one question, though. HOW do the arms get that short in battroid? They practically double in length, when it goes to fighter mode! ~Luke Edit: Oops, messed up on shoulder pivot point. New image.

Well, if you want to get picky... What's with the magenta on the thrust-vector paddles?! Still, I love the sculpt. ~Luke

Looking VERY nice. That'll look great in the air. ~Luke

Very nice, very nice. By the way, you can sand down any wrinkles in the tissue that really get to you. I'd used 300-400 grit. Maybe use a bit of white glue thinned with water, just to make sure the edges are tacked down. ~Luke

Just to point out: The XPlane modeling software is pretty nasty, when it comes down to it. I've used it a few times, and even modeling a fairly simple aircraft is quite a pain. To do something like a VF is very impressive. ~Luke

"...Your insane you know that right..." Yep, people over on RC-Groups have told me that repeatedly. Well, the turbines are being saved for the 1/6 scale version. (Joking. Well, not joking, if I could afford them!) I should learn composite fabrication, though. Cool8or, thanks for the complements! This is "medium-high-tech" for RC, I'd say, but if I have my way, "you ain't seen nutt'n yet!" ~Luke

If you think the -21 is crazy... This is another idea that's been running in the back of my head for the past few months... 60" long, variable geometry wings (actuated by micro-jackscrews), retracting gear, variable 'diameter' thrust-vector system, retracts, custom flight computer (for improved high alpha flight), and over 1:1 thrust/weight, even without the option of functional boosters (extra 10 oz. of thrust per). All for 32 oz., AUW. Not as far-fetched as it sounds, actually. I've already bought a set of motors, and I've crunched numbers for the fans, batteries, and wing jackscrew system. We'll see. I have sort of done the -51 to death, though. Anyway, right now, I'm working on my 3D digitizer, so I can non-destructively pull cross-sections from plastic models, with accuracy down to 0.001" or so. ~Luke

Very good. You got the ArtTech Su-27, right? (Twin ducted fan RTF?) If so, I'm pretty sure that this now has a better thrust/weight ratio than the -27 does with the stock motors, so transitioning from one to the other should be pretty easy. ~Luke

Well, I have a few ideas... Here's one. (Big ship, 57" long, better than 1:1 thrust/weight ratio, retracting gear, folding wings.) ~Luke

I'd say that thinned Tamiya would be fine. You've got about 0.3 oz to play with, and still come in at the same flying weight as you see in the video. (The comb I used to balance it is about that weight, and obviously, I'll be removing that and nudging the battery forward instead.) After that, you probably have another 0.5 oz., or so, before I'd start really getting worried. (Having said that, I of course strongly recommend keeping things as light as possible.) As a side-note, I was really impressed with the duration, 9-10 minutes is a pretty long time for any ducted fan ship, much less a fighter-type design. ~Luke

Glad you like it! There's so many improvements on your ship, I think I'd do better just to build myself another, rather than try retrofits. However, I've got my eye on some other (Macross) aircraft right now, so once I get this shipped to you, we'll see what I end up doing. ~Luke