Incorrect assumptions, NARAM 57, Hellfire XX, and subsequent L2 decisions/dilemma

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75Grandville

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My plan was to go for my L2 with a Wildman Darkstar Jr., back in May, at a UROC launch. But, it got rained out, and since I knew the forecast, I didn't get everything quite together.

So then I was going to do it in June. I even passed the written test at our contest launch (Pioneer 2015). But the forecast all week was showing rain for that Saturday, and I figured that the launch would be cancelled. I was wrong! The launch went off as planned. And me still lacking charge wells, and a couple of fillets shy of a finished rocket. For the record, I still have two more internal and four sets of external fillets to go, paint, and ground testing to do.

I was thinking it would be kinda cool to level up at NARAM, since I got my L1 at NARAM last year. HOWEVER, the ceiling is 6,500 AGL, and any J I put in the Darkstar Jr is going to go at least 7,000.

So, here's the dilemma: I can wait until the end of that week, and just do it at Hellfire XX - 10,000' AGL with call-in windows to 25,000'. Or, I could buy something else and get my L2 on something "low-and-slow" with the 54mm casing I picked up a few weeks back. Something like:

  • A Binder Designs Velociraptor. I hadn't realized how complete that kit is! Sims to 4,500' on a small J
  • A Wildman Interceptor A.A.D. 98 Love the sale price, love the design, adding shock cords, a chute, etc is going to put this into the $400+ range. But maybe I could cert on a K...
  • Upscale a 3D Rocketry FS2 to 4"/54mm. Waiting to hear back from Bill at 3D Rocketry about his thoughts. I like to ask permission before upscaling - it's just one of those things.
  • Or any of the other cool kits/designs out there. Too. Darn. Many. Choices!!!

So, the true question: Do I just finish building the rocket(s) I already have, build my contest rockets, and spend all my $ on motors to burn at Hellfire, or do I buy something big, pour all of my money into that, and keep it more restrained? If I buy a new rocket, I think I'll probably need to skip the 38/1320 casing I was planning to buy, and some of the bigger reloads. And the reality is that I have several cool things in my HPR build pile that I would love to finish before NARAM.

I know which way I'm leaning, but hey, why not get some more feedback?

Other thoughts:
  1. Why do NARAM 57 and Hellfire XX have to overlap by two days? Launching at NARAM Thu AM, driving ~8 hrs, then getting up early on Fri to drive 4 more hrs to launch on Friday at Hellfire.
  2. Why don't my wife and kids want to spend 9 days in the desert/salt flats launching rockets in August? (This one is rhetorical, I guess)
  3. Why did my wife give me the OK to go by myself (this one still stumps me)?
  4. Will my 10 year old Scion hold all my junk, and make the 1,700 mile trip intact?
  5. What is the capital of Assyria?
 
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[*]Why do NARAM 57 and Hellfire XX have to overlap by two days? Launching at NARAM Thu AM, driving ~8 hrs, then getting up early on Fri to drive 4 more hrs to launch on Friday at Hellfire.
Don't know
[*]Why don't my wife and kids want to spend 9 days in the desert/salt flats launching rockets in August? (This one is rhetorical, I guess)
Don't know
[*]Why did my wife give me the OK to go by myself (this one still stumps me)?
Don't know but I smell a trap
[*]Will my 10 year old Scion hold all my junk, and make the 1,700 mile trip intact?
Don't know
[*]What is the capital of Assyria?
Nineveh

[/QUOTE]
 
If it helps any, I will be for there for all of NARAM 57 and you are welcome to borrow my 38/1320 casing at the event. The J510 is awesome reload for larger rockets.
 
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I was thinking it would be kinda cool to level up at NARAM, since I got my L1 at NARAM last year. HOWEVER, the ceiling is 6,500 AGL, and any J I put in the Darkstar Jr is going to go at least 7,000.
Hmmm.....I downloaded the rocksim and got those really high altitudes as well. Gotta wonder if there's an issue with the file..I'd fly it on a I and see how it does compared to the predicted. My Wildman JR does 5280 on a J381. Can't imagine the darkstar, with more draggy split fins, would be 7,108, beating it by 1700 feet.
 
Thanks for the offer. However, I am pretty sure I would blow through the waiver with anything I've currently got! I was hoping to stuff the 1320 into the Darkstar Jr. at Hellfire and take a crack at Mach 1 & 10k


If it helps any, I will be for there for all of NARAM 57 and you are welcome to borrow my 38/1320 casing at the event. The J510 is awesome reload for larger rockets.
 
Thanks for that info! Still need to get my final dry weight, and run the sims with that. I will do some flights at NARAM and see what I actually get on an H and maybe an I.

Which will require that I actually finish the rocket!

I'm coming down the home stretch - may even finish the epoxy tonight if I am feeling especially energetic. One more internal and two more sets of external to go. Then an appt with my drill press and some paint, and some muffled "Bang"s from my back yard and I'll be all set!

Hmmm.....I downloaded the rocksim and got those really high altitudes as well. Gotta wonder if there's an issue with the file..I'd fly it on a I and see how it does compared to the predicted. My Wildman JR does 5280 on a J381. Can't imagine the darkstar, with more draggy split fins, would be 7,108, beating it by 1700 feet.
 
Did she say do whatever you want. Because that's not permission, it's a challenge.

TA
 
Have you thought about adding about 1.25 to 1.5 pounds of weight to the inside of the nose cone. Using the RocSim file from Wildman's site that brings the Jr down to less than 6000 feet on an AT J350 or CTI J-400SS (about 700n/sec total). Just put a couple of 1.5 inch long screws up inside the base of the NC and then pour the required weight of epoxy into the NC tip it upright (so epoxy settles around the screws) and stick it into an ice bucket to keep the NC from melting as the epoxy cures.
 
Have you thought about adding about 1.25 to 1.5 pounds of weight to the inside of the nose cone. Using the RocSim file from Wildman's site that brings the Jr down to less than 6000 feet on an AT J350 or CTI J-400SS (about 700n/sec total). Just put a couple of 1.5 inch long screws up inside the base of the NC and then pour the required weight of epoxy into the NC tip it upright (so epoxy settles around the screws) and stick it into an ice bucket to keep the NC from melting as the epoxy cures.

Interesting thought. More likely to stack a series of washers inside the NC than to make the weight permanent. I swapped out the screw holding the aluminum tip with a piece of all-thread, and added an eye-nut to allow for future expansion. Could easily add weight that way. Would need to see what that would do to everything else, though. I sized the 36" main to the weight as built, would definitely want to see descent rate with the extra weight.
 
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