We Can Rebuild This Bird

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DynaSoar

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Due to lack of instructions regarding using S/U motors with a Slimline retainer, this is what was left of my Mirage. There's about a foot of tube missing here because I tore it to pieces getting one of the couplers and bulkheads out of it. Notice the very nicely symetrical folding on the nose, indicating a very nearly perfectly vertical China seeking trajectory. The motor section was actually worse off. This is after having glued the surviving part (right to the leading edge of the fins) to a second salvaged section (making it 27" long) and filling the spiral cracks with spackling.
 
And here's the ex-Mirage in the pangs of rebirth, with the previous Mirage motor/fin section, plus 4.5' of quantum tubing, a PML urethane tail cone inverted to be a transition, 1.5' of phenolic 38mm payload section and a PML urethane conical nose. Farewell, Mirage. Behold, the Deja Vu.

This WILL fly at the next DARS launch (where it crashed) on the G80 it was supposed to fly one, and then on to some Ellis HPR motors.
 
Sorry to see your extremely "unhappy" rocket...Good luck in the resurrection.

"Where do you hook up the neck electrodes?"

Sorry...Being a Smart@$$...
 
Since the original design was for this bird to land nose first, and I'd replaced the upper section with phenolic, I needed to make it tough enough to handle the landings.

First, I did as was suggested and rigged it for single parachute, with the booster landing well ahead of the rest in order to take the strain off. Still, the phenolic wasn't enough as is.

After filling the spirals with spackle, I wrapped it with 5 layers of self-adhesive vinyl, actually shelving "paper". The adhesive was weak so I first sprayed it with 3M 77 adhesive as I wrapped. (This, with the assistance of the guys from Rocketguts. No way I could spray and wrap this monster with two hands).

Then I got a couple feet of 2" heat shrink tube. I slid it down over the tube and onto the transition as far as I could. I tried using a 1600 watt hair dryer to shrink it but it wasn't enough. I tried that plus a ceramic room heater, and that was enough to trip the circuit breakers. So, I cranked up the broiler in the kitchen oven and did a hand-rotisserie bit with it.

At first it shrank unevenly leaving wrinkles. Then it kept shrinking and got rid of the wrinkles. Finally it started getting bubbles in it where the vinyl underneath started to fume. So, I took it out and let it cool slowly to let the bubbles shrink back.

Finally, I trimmed off the excess at the top, and wicked light CyA around the top of the tube as well as the joint over the transition.

Now, with 1/8" wall of vinyl and rubber over the phenolic, either it's tough enough to handle the landings, or I'll switch to nerf.

No painting started yet. When I do, I'll use appliance epoxy which will add significant weight. As is, it's now at 3 lbs 12.5 ounces. The MMT is 29mm, but it can handle up to 11" of casing, so there's still a few motors it can use. It *might* be able to get up to 500 feet with a G80, or maybe a little more with a G110, but I think my best bet for this bird will be an Ellis H275.

One more thing it needs: rail buttons. > 4 pounds with motor is just too much for 1/4" rod.
 
Rail is a great way to go, however yyou might also consider 1/2" lugs. We always seem to have a queue at the rail/

Have you considered an I69?

That thing scream dual deploy. or paossibly triple given the length to dia ratio.:p

I do have to admit that the shelf paper/heatshrink was the singular most novel assembly technique I've ever heard of.

BTW I'm Cloning the LAMP based on a Fatboy. The only Difference is the NC lights up from inside with four 20,000mCD LEDs


We miss ya Doc. Will I be able to fly in Feb when I come to HIMSS?


That makes 900 posts :D . Time for bed.
 
Originally posted by Hospital_Rocket
Rail is a great way to go, however yyou might also consider 1/2" lugs. We always seem to have a queue at the rail/

Have you considered an I69?

That thing scream dual deploy. or paossibly triple given the length to dia ratio.:p

I do have to admit that the shelf paper/heatshrink was the singular most novel assembly technique I've ever heard of.

BTW I'm Cloning the LAMP based on a Fatboy. The only Difference is the NC lights up from inside with four 20,000mCD LEDs


We miss ya Doc. Will I be able to fly in Feb when I come to HIMSS?


Working on the launch schedule.

The Jefferies tube is 11" long, hence EM's H50 or H275. The I169 is 16" long.

Rail buttons are next to go on, after the paint dries. After that goes motor and ring clips into the Slimline.

Here it is from the business end, on the drying rack.
 
Payload section (vinyl wrapped and heat shrink tube coated tube with urethane conical nose and transition {tail cone}, all from PML) internal 1.5" diameter x 16" deep.
 
Length 106", weight 56 ounces.
Main diameter 2.6", motor tube 29mm x 11".
(AT ejection baffle retained).

Paints: Cherry red gloss, metallic gold, black appliance epoxy, all Rustoleum. No clear coat. Maybe acrylic later if it's compatable with the gold.

Here it is from the scary end.
 
A better sense of scale. Half meter T-square hanging from the door frame.
 
Wow! That looks awesome! Can't wait to see it with a big flame out the back end...if I could suggest - a red flame would be great!

Loopy
 
Originally posted by n3tjm
Swwweeeeeeetttttt looking rocket you got there :)

May I suggest a I200 :D.

13.1" length. Won't fit in the tube. The most length I could get out of it and still have the baffle was 11". There's still plenty to choose from, G64 and G80 and a lot of H's. I'd planned on the Ellis H50 when building it, but the H275 would fit and be a much more impressive liftoff.
 
Originally posted by DynaSoar
13.1" length. Won't fit in the tube. The most length I could get out of it and still have the baffle was 11".

May not fit all the way in but that rocket is so long that it's veeeeeerrrry overstable so you could have a motor hanging a couple inches out the back & still have an arrow straight flight...

Besides, weighing in at 56oz, you'd get some decent altitude out of that bird on an I200 ;)
 
Originally posted by lalligood
May not fit all the way in but that rocket is so long that it's veeeeeerrrry overstable so you could have a motor hanging a couple inches out the back & still have an arrow straight flight...

Besides, weighing in at 56oz, you'd get some decent altitude out of that bird on an I200 ;)

Looks to be a bit over 2100' at 10 seconds. Can get a couple hundred more out of an Ellis I69 S/U.

Other "problem": Slimline retainer. I don't fly without positive motor retention both directions. Now, if there were a way to add a moveable thrust ring mid-casing, it could work. No heartburn doing that with an S/U.

Besides, the 29/360 is hardly a deal. $90 for a motor that fits no other casings. Or did they change that?
 
The 29/360 closures are fully compatible with the 29/60, 29/100, 29/120, 29/180, & 29/240 casings. You only need the forward seal disc for some or all (not sure how many) 29/360 & 29/240 BT reloads.

HTH,
 
Flew it at McGregor TX on May 28, on an Ellis Mountain H275-10.
An 87% H burning in 1.1 seconds makes for a neck-snapper. Don't know if anyone else managed to catch it going up, but I sure couldn't have.

The sim said 1900' with ejection 1/2 second past apogee. It may have topped out early or may have been a long delay. Ejection was about 2 seconds past. But, it was starting to fall sideways rather than going ballistic, and so I could see the length of it quite clearly when it did pop. The modified Mirage fin can recovery section worked perfectly, and the 70" X-form brought it down slowly and safely 500 feet from the pad.

A pretty flight, but more than that a very satisfying win over a previous failure.
 
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