New SSS/SSSS Thread

[Bruce R. Schaefer]

Well, since so many different techniques were used in all the rockets, this is going to be a real good contest in comparing the effects in all of them. Very nice.

[Chris LaPanse]

It’ll be an interesting comparison between mine and yours…

My finish is relatively crude compared to yours (from the sound of it), but on the other hand, the ultralight cf allowed me to shrink the fins slightly and allowed a little more leeway on the design. It’ll be interesting to see which effect has more impact…

[Bruce R. Schaefer]

I did final weight on my SSS today. And, I had to laugh… here I am trying to find the optimum weight or mass from a faulty WRASP file. You can’t win. And, I think that’s why this is such a great contest this year. C’mon, if you have sound .eng files, how hard is it to meet what the sim says it should be? So I backed off on the weight. 13.5 ounces. That should be fine. It’s a crap shoot anyway… especially on the prairie, if you know what I mean. 🙂

[Chris LaPanse]

13.5 😯 😯 😯

Mine is at what simmed to be optimum mass for me, which is 8.6 oz with motor.

How did you get 13.5 oz of rocket?

At least yours will be easier to track off the pad… 🙄

[Anonymous]

*IF* I get out there and *IF* we find someone to pull the trailer (last I heard that was still an issue) and *IF* I have room, I’ll bring my 8″ Dobsonian telescope so everyone can use it for tracking their SSS. I’ll give you some quick training. It is basically a very stable, very large binocular that is missing one of the eyepieces 🙂 This was discussed in an earlier thread, and there seemed to be no objection to using the scope.

I have a wide angle eyepiece that should yield perhaps 10X magnification. It will be much more effective than using binocs. You will be able to sweep the sky in orderly fashion.

DISCLAIMER: I will not be held responsible if you swing the telescope toward the sun fry your eyes 😯 I’m very serious — use at your own risk, please. Even a brief glimpse at the sun w/o filters will be painful.

[Bruce R. Schaefer]

Listen to JW. Remember how some kids would burn ants with a magnifying glass? This is far more powerful. So don’t get excited and accidentally look for your rocket in the sun. It’ll be the last thing you see. 😯

[Bruce R. Schaefer]

Bob’s rocket was 10 ounces. Mine was 10 something, but simmed at a lower altitude. Remember mass. If you get 13.5 ounces flying fast, which will go farther… 13.5 ounces or 8 ounces? Think momentum. Of course, 8 ounces will get up a little quicker… but what mass will keep moving longer after burnout? I tied really heavy washers to the Kevlar harness in order to bump it up 3.5 ounces. This is just a trade-off I made. We’ll see if it pays off. Might, or Might not. That’s the game. 🙂

[Chris LaPanse]

I realize that. Mine has quite a high ballistic coefficient though, and keep in mind that I have smaller fins. Rocksim says that I have optimum mass, though we’ll have to see…

Should be interesting, no question

[Bruce R. Schaefer]

Since I haven’t used Rocksim since it first came out, and I use SpaceCAD, does Rocksim allow you to add a weight and change it so you can see, in simulation, the change in altitude? Chris, at this point, we’ll just see what happens. With these G80’s prone to CATO and depending on the MAWD to ignite the drogue charge, etc., all I want is a safe flight… with my MAWD back. 🙂 As Bob Messener said, “There are so many variables…” And, that’s right. In this case, may the best and LUCKIEST man win. 😉

Another note: my speed multiplies out to 974.1 m/hr. What’s Mach 1 at NCR’s sites? 760 m/hr? Or what? If it’s close to 760, then I’m at Mach 1.28. Oh boy… this can’t be right? Okay, checked online, and it’s 717 m/hr. It was always my understanding that the number changes with location, as in altitude? If not, then it’s Mach 1.35… maybe I should have used a pointy nosecone… 🙂 Ah, second thought get you into trouble…

[Chris LaPanse]

930?

How on earth…

Mine sims at 830, and it is lighter and (theoretically) less draggy than yours…

That sounds like bad motor sim data to me…

As for the rocksim question – it has a feature where it runs a lot of sims tweaking the mass slightly, and then tells you the optimum mass. Really handy at times (and it predicts my optimum mass as 8.4oz, so I’m a hair over).

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