Multiple Streamers?

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BigMacDaddy

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Has anyone seen a recovery solution that uses multiple streamers? I was imagining something like a small / simple umbrella mechanism to hold several streamers away from each other to create maximum drag for recovery.

I want to make a Pelon rocket. Pelons are a Mexican tamarind candy that you push up from below and hairs of candy come out (kinda like the Play-doh barber shop). Anyway, thought that the multiple streamers would be reminiscent of the candy. The nosecone would obviously just be that plastic rocket-shaped candy container.

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BABAR

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Sounds like a cool idea, I’d say just build and fly it. It’s likely to come down harder than a chute, but the only streamer rule I know is the 10-1 rule for a single streamer, that being that once the length to width ratio exceeds 10 to 1 you get little if any bang for your buck for a longer streamer.

my GUESS is that two separate 10x1 inch streamers would act more like one 2x10 streamer than one 1x20 streamer, but I don’t know for sure. Seems like it would be a good science project. I think the new flight sketch mini tracks descent speed and fits a small rocket, so wouldn’t be hard to do.
 

afadeev

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I would carefully consider the prospect of multiple streamers tangling together, and diminishing effectiveness to below that of a single streamer.
I am not sure how to model that, so if sufficiently motivated to proceed, experimentation on a sacrificial rocket may be warranted.

Personally, if I don't find a single streamer up to the task of slowing the rocket down to the desired descent rate, I model small chutes instead.

YMMV,
a
 

boomtube-mk2

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I've successfully used multiple streamers on a couple of rockets.
Make your "Shock cord"* really long, then attach one streamer just below the nose cone and the other at the point where the cord just clears the body tube.
Roll and insert the first streamer, and push down until it is just above the wadding.
Fold the shock cord that lies between the streamers and insert into the body tube.
Put a bit of wadding/dogbarf into the tube then roll and insert the second streamer.

For this to work I suggest you use lightweight Kevlar for the "Shock cord".
 

BigMacDaddy

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Thanks everyone for sharing insights!

my GUESS is that two separate 10x1 inch streamers would act more like one 2x10 streamer than one 1x20 streamer, but I don’t know for sure.
I have a bunch of the standard orange streamers from a 12-pack of Viking rockets so that is what I was planning to use -- either 6 or 8 of them...

I would carefully consider the prospect of multiple streamers tangling together, and diminishing effectiveness to below that of a single streamer.
Yeah for sure, I was not sure about how to best "pack them" to avoid tangling. I was thinking about a simple small 3D printed part that would let 6 or 8 bamboo skewer sticks "open up" with streamers attached at the ends (with main body of rocket attached at middle and proving the weight to pull down middle and let wind push up streamers). It does seem like a recipe for a tangle... Maybe I could put a small parachute over the frame so that it catches air itself and is forced open / upright so streamers stay away from each other...

I've successfully used multiple streamers on a couple of rockets.
Thanks for sharing your experience doing this. Made me consider alternative options -- for example, I could do a Wacky Wiggler-type break-up of the body tube with streamers in each separate section. Not exactly like the candy but could work and be a bit less likely to tangle.
 

manixFan

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One method I used for multiple streamers was to tape them along a very thin piece of music wire, and attach a riser from the main shock cord to the center of the wire. I then curled the wire so it slid inside the body tube. For this to work the tube diameter needs to be pretty large. When the music wire pops out it straightens out and keeps the streamers away from each other. I only used it on one rocket and as I recall it worked. My biggest concern was making sure it didn't hang up inside the rocket. I had the riser attached very near the nose cone so that it would help pull the assembly out.

Just a thought.


Tony
 

Zbench

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While low power, current incarnations of the Estes goblin use two short streamers. I flew it a few weeks back. While the streamers didn’t tangle, it didn’t really slow the rocket much as when it hit the ground in a grass field, one of the fins broke off. It is rehabbed, I’m going to use a single streamer twice as long as what was recommended and see how that might change things.
 

BABAR

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While low power, current incarnations of the Estes goblin use two short streamers. I flew it a few weeks back. While the streamers didn’t tangle, it didn’t really slow the rocket much as when it hit the ground in a grass field, one of the fins broke off. It is rehabbed, I’m going to use a single streamer twice as long as what was recommended and see how that might change things.
Please let us know how that goes. My understanding is that anything over ten to one is superfluous. I‘m not sure that include if you corrugate it.

this may or may not be of use to you

 

gldknght

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While low power, current incarnations of the Estes goblin use two short streamers. I flew it a few weeks back. While the streamers didn’t tangle, it didn’t really slow the rocket much as when it hit the ground in a grass field, one of the fins broke off. It is rehabbed, I’m going to use a single streamer twice as long as what was recommended and see how that might change things.

The same exact thing happened to me last weekend. Flew my Estes Goblin on a D12-5, perfect streamer deployment, broke one fin on landing. I might try adding a third streamer of the same length to the two already in there...
 
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