DynaSoar
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Just finished an AT Mirage I'd been working on for a couple months. I never take this long, but I was designing in some mods I wanted, and trying to make sure those would work with the bird.
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The kit itself, parts and instructions, is exactly what you expect from AT.
The mods were a combination of a Slimnline mtor retainer and a PML urethane tail cone. Putting these in required some careful jiggling around of parts and distances to make sure it all went together, because building with the FinLok system can be very unforgiving.
The PML tail cone fit over the AT motor tube with room to spare. Alas, not enough room for the Slimline to be recessed within nthe tail cone. I had a choice: Slimline protruding, or drill a 1.5" hole halfway through the existing 1.25" hole The diufferece would be (a) seeing 1 inch of black below the cone and (b) 1/2" further aft along the axis for the retainer ring.
I went with the latter, since I wanted to mod the motor mount for the longest possible engine. So, the (black cylindrical) Slimline sticks out 1 inch from the aft end of the (1.75" long, appx 45 degree conical, chrome) tailcone. Recessed would have been a better engineering job, but sticking out works fine and looks cooler.
Moding the motor tube meant figuring out how much tube I could stuff with motor (adding 1/2 inch for the protruding slimline). The AT tube was 13". I managed to get the baffle material and baffle head to fit in the top 2", so I set the internal mtoor block at 10.5", making max engine length 11"
Other mods to the Mirage: competely painted first. This would have been fine, had I been aware of a couple of details. The body is six coats (a full can) of cobalt blue metal flake (over aluminum base, over primer) protecting by a full can of clear gloss. The finish was superb. Sadly, when I glued the lugs on using CyA, I got the little white crystals growing around the lugs. Icky.
The nose didn't take well to painting, despite my having prepped it just like the ones I'd successfully done before. The difference here I thinkw as the use of satin finish between the primer and chrome. It took a week to dry, and even then, would get smudged and flat-looking where ever it was touched. And it's hard to put AT fins into the FinLok, and put the nose on anything, without touching it.
I can always mask off the body and give the fins a coat, but they'd just get smudged again. And the nose is starting to get uneven spaces where previous layers peeled and I sanded AND tried repaining. I might just get a replacement cone.
OH, last mod was putting a floor in the top body section , making it a payload section.
I went ahead and let it as a two-piece recovery rather than strapping them together. I've got a G64 to test it on (it wouldn't take less, since it weighed more than 8 ounces greater than its nominal 31 oz) and if it looks like two separate recoveries will be a problem, I can always tie the ends of the shock cords with an additional cord, as long as it's long enough to let one hang entirely below the other.
With the tailcone and Slimline sticking out the bottom, it appears that it would be fairly easy to build something like a Tiny TIm type booster that'd fit snug up against this thing, kick it up a couple thousand feet, and light off an H (which is what the MMT was modded for) to see if I can get a mile out of this enormous, 7 foot, 3 pound bird.
What I'd suggest to RockSimmers, get the Mirage file and try it without the top third of the body, what I made the payload section. If you just used the motor and chute sections, most of the second length is still empty, and it could easily carry stuff, or possibly even fly on its own, with some balancing needed no doubt.
Test flight planned for CATO launch Aug 21.
\
The kit itself, parts and instructions, is exactly what you expect from AT.
The mods were a combination of a Slimnline mtor retainer and a PML urethane tail cone. Putting these in required some careful jiggling around of parts and distances to make sure it all went together, because building with the FinLok system can be very unforgiving.
The PML tail cone fit over the AT motor tube with room to spare. Alas, not enough room for the Slimline to be recessed within nthe tail cone. I had a choice: Slimline protruding, or drill a 1.5" hole halfway through the existing 1.25" hole The diufferece would be (a) seeing 1 inch of black below the cone and (b) 1/2" further aft along the axis for the retainer ring.
I went with the latter, since I wanted to mod the motor mount for the longest possible engine. So, the (black cylindrical) Slimline sticks out 1 inch from the aft end of the (1.75" long, appx 45 degree conical, chrome) tailcone. Recessed would have been a better engineering job, but sticking out works fine and looks cooler.
Moding the motor tube meant figuring out how much tube I could stuff with motor (adding 1/2 inch for the protruding slimline). The AT tube was 13". I managed to get the baffle material and baffle head to fit in the top 2", so I set the internal mtoor block at 10.5", making max engine length 11"
Other mods to the Mirage: competely painted first. This would have been fine, had I been aware of a couple of details. The body is six coats (a full can) of cobalt blue metal flake (over aluminum base, over primer) protecting by a full can of clear gloss. The finish was superb. Sadly, when I glued the lugs on using CyA, I got the little white crystals growing around the lugs. Icky.
The nose didn't take well to painting, despite my having prepped it just like the ones I'd successfully done before. The difference here I thinkw as the use of satin finish between the primer and chrome. It took a week to dry, and even then, would get smudged and flat-looking where ever it was touched. And it's hard to put AT fins into the FinLok, and put the nose on anything, without touching it.
I can always mask off the body and give the fins a coat, but they'd just get smudged again. And the nose is starting to get uneven spaces where previous layers peeled and I sanded AND tried repaining. I might just get a replacement cone.
OH, last mod was putting a floor in the top body section , making it a payload section.
I went ahead and let it as a two-piece recovery rather than strapping them together. I've got a G64 to test it on (it wouldn't take less, since it weighed more than 8 ounces greater than its nominal 31 oz) and if it looks like two separate recoveries will be a problem, I can always tie the ends of the shock cords with an additional cord, as long as it's long enough to let one hang entirely below the other.
With the tailcone and Slimline sticking out the bottom, it appears that it would be fairly easy to build something like a Tiny TIm type booster that'd fit snug up against this thing, kick it up a couple thousand feet, and light off an H (which is what the MMT was modded for) to see if I can get a mile out of this enormous, 7 foot, 3 pound bird.
What I'd suggest to RockSimmers, get the Mirage file and try it without the top third of the body, what I made the payload section. If you just used the motor and chute sections, most of the second length is still empty, and it could easily carry stuff, or possibly even fly on its own, with some balancing needed no doubt.
Test flight planned for CATO launch Aug 21.
