It would have everything to do with it. See post #76

http://forums.rocketshoppe.com/show...54&postcount=76

I'm still trying to justify buying some Chinese ammo to see what they contaminate lead bullets with

Anyone actually flown a Star Stryker yet? Mine should be flyable for a launch tomorrow. All I have left to do is decals, and I'm going to do that while I eat my lunch (in just a few minutes). I didn't have black paint on hand, so mine's red and blue.

I'm mainly wondering about a 12 inch chute in a BT-20 tube and getting it out again reliably (I also have this concern about the Moon Mutt, which I tossed together last night). I have chutes attached with swivels and will prepare some streamers tonight - but I always try to build/fly the way it's designed at least at first.

Added later:

Someone noted earlier that there are six fin decals and five fins....it turns out one of the six is different and doesn't go all the way to the fin tip.

This is my first go at waterslide decals in a long long time (I favor sign vinyl and stick-on trim for my airplanes). I need practice, unfortunately.

I agree with commenters below...a smaller chute is probably the way to go on this one, but we'll see. I expect to put the How High altimeter in the Star Stryker, which will add 1/4 ounce or so.

On the Moon Mutt (which weighs all of .74 ounce with the chute stuffed in it), I'm likely to go to a small streamer after one trial (if it doesn't float away on that trial )

Estes uses a 12" chute because that's the smallest chute they make; not because it's the most suitable. That is, they give you what they have, not what's necessarily best for the rocket.

I agree that getting a 12" chute in a BT-20 is problematic. For smaller rockets, I have made smaller chutes. One simple way of doing that is cutting the Estes chute down to size. However, for a pre-strung chute that implies cutting and reattaching or replacing the strings. It'd be easier to start from scratch with an unassembled chute and take 1.5" - 2" off all the way around (resulting in an 8-9" chute). Or get some scrap plastic and roll your own. This has the advantage of allowing you to pick some thinner material which will pack more easily thus allowing a bit larger chute.

Normally, for a BT-20 based bird, a 7-9" chute is sufficient, but with the payload section and extra fins, this rocket looks to be on the heavy side, so another 2-3" of chute could be helpful. OTOH, if you can position the chute on the shock cord in such as way as to have the nosecone hit the ground first, then you can get by with less chute. But make sure you have enough slack in the shock cord to pull the chute out of the airframe before it goes taut. IOW, don't connect the chute on the shock cord too close to the rocket.

When I became a BAR, I started out building chutes down to 6" and using them in everything I flew having carried over from childhood the (false) paradigm that streamers weren't as good. But over time, I've seen the light and have found several advantages to streamers. In the case of BT-20 birds, a crepe paper streamer 2" wide and up to ~40" in length can be rolled up and put in the bird without being jammed in place. Wrapping a couple turns of shock cord around it keeps it from unrolling/expanding itself and becoming lodged in place.

The net advantages are that enough streamer can be packed in to equal the drag of a chute while being simpler to pack, and streamers open without the jerk loading that chutes present when deployed late or early as sometimes happens.

Anyway, I agree with your idea of trying to fly it stock, but a (stock) 12" chute in a BT-20 isn't an ergonomically good combination.

Doug

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Use an expended casing installed the "right" way, and stick a launch rod in the nozzle. Then, you can easily erase the launch rod with a "clone brush" tool (such as is found in the Gimp or in Photoshop).

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Once upon a better day... SAM #0076
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Mine hasn't flown yet. I just finished putting on the decals last night. Once the weather calms down a bit, I'll give a test shot. A8-3, of course.....perhaps a B4. I left off the motor hook and will friction fit the motors. The stock chute won't be used either. Probably go with a streamer or 8" chute.

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This may have been mentioned before, but on the Moon Mutt's box there is a panel where it states that you'll need a launch system to fly the Moon Mutt and I think it says not included. I don't have it here at work with me. :-) On another panel a picture of the launch system is shown. A bit contradictory, unless I misread or am misremembering something.

The Moon Mutt seems almost identical to the Fire Hawk. I think that must be the same fin can. I'm not sure about the nose and the tube may be slightly shorter.

I flew a Taser Twin at the last AARG launch in Bertram. I used a B6-0 and an A8-5. I had my eye on the booster, so I don't know how OOS the sustainer was, but there were folks at the launch who had their eye on the sustainer and were able to point me at it. Even with the streamer it drifted a good long way down wind, but I got it back.

I wouldn't try that in a school yard though.

The Moon Mutt comes with a standard Electron Beam controller and a small non-adjustable tripod launch stand with wooden dowel legs and a half-length two-piece launch rod. All of this for $9.97 at WM.

So, all one needs to add is four AA batteries, and engines/wadding/igniters.

I'm not familiar with the Fire Hawk. The MM is a four-fin plastic fin can (two pieces - three including the "launch lug"), a long ogive plastic nose cone and 7 inches (IIRC) of BT-20. Motor retention is by twist-on ring.

Looking at the Fire Hawk description and instruction sheet on estesrockets.com I'd say you're right - same thing with different stickers - and no mention of an A impulse engine alternative.

I wasn't very clear. I realize that there is a launch system included because I bought a Moon Mutt, plus I had read the reports here. But for the less fortunate with less information available, they might be confused by the contradictory box panels--assuming I am remembering correctly and they actually are contradictory.

Here is Austin, out of about six Walmarts I've visited over the last month or two, I only saw the Moon Mutt at one Walmart. Most of them had the four new rocket kits, but only one had the Moon Mutt. And engines seem to be uniformly $5.97 per pack now.