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...
 

GlenP

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you could have one regular chute or streamer on a long shock cord, and use shorter lengths of yarn for the candy hair effect, rather than relying on them for recovery itself, they are more for the decoration.
 

BigMacDaddy

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you could have one regular chute or streamer on a long shock cord, and use shorter lengths of yarn for the candy hair effect, rather than relying on them for recovery itself, they are more for the decoration.
That is an interesting idea... I had thought of having a small parachute that would hold open the frame that the streamers were mounted to but it might be more realistic to size the parachute up a bit more and rely on it.
 

David Schwantz

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I have used 2 streamers before. 38MD rocket. They were not intended to slow rocket much, but more for being able to see it. They did not tangle, I did nothing fancy for packing other then normal blanket/ burrito method. Saturday I flew a 50' streamer on a 4" Black Hole, did not want it to slow rocket much due to altitude it would reach. Again wanted it for sight, it worked great could see the descent the whole way down. It did twist a bit though.
 

StevenM

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Hello, I've been flying rockets for many years, but relatively new to the forum (first post). The multiple streamer topic caught my eye and I thought I would share a video made back in 2013. The rocket is called the Rainbow Fish (named after a popular children's book) and is flying on a C6-3. It recovers on three crepe paper rainbow colored streamers and a small parachute. The streamers are each attached to basswood spars that spring/pivot out away from the top of the BT-60 airframe (three small piano-wire springs keep each spar under tension until the nose cone ejects).

The intent of the design was to see if the streamers would increase the rocket's effective rotational inertia and reduce the rocket spinning during recovery, and thus improve the watchability of a keychain video camera strapped to the outside of the airframe. It did take some extra time to prep in order to carefully fold each streamer and the parachute while getting the nose cone in place with spring loaded spars all together.

It was a fun project, seemed to confirm that this was one of many concepts that could be used to help decrease rocket rotation during recovery, and also tracks with some of the ideas described by others in this thread.
 

BigMacDaddy

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The streamers are each attached to basswood spars that spring/pivot out away from the top of the BT-60 airframe (three small piano-wire springs keep each spar under tension until the nose cone ejects).
This is great -- do you have any closer pictures of the mechanism to deploy the multiple streamers? Also any advice about packing these inside the rocket to avoid tangling or other deployment failure? Thanks!
 

GlenP

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The intent of the design was to see if the streamers would increase the rocket's effective rotational inertia and reduce the rocket spinning during recovery, and thus improve the watchability of a keychain video camera strapped to the outside of the airframe....
looks like that worked pretty well, do you have any keychain video with this one yet? I was thinking that one streamer on a long external shock cord attached to a single fin would also have a similar weathervane effect, to keep the rocket from spinning around while drifting on a chute. Maybe even a non-symmetric fin, i.e. one longer dorsal fin, would act like a weathervane during recovery. I have not experimented with these ideas myself yet.
 

StevenM

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Good questions, since I still have the rocket, below is an image showing the rocket after the nose cone has been removed. Important features include:

1. The three folded/rolled streamers slightly sticking out of the top of the body tube. Slack riser-lines lead from each streamer to the top of each spar.
2. Deployed basswood spars, retained by the "taut" white string (strong upholstery thread) toward the middle of each spar, also note fishing swivels at the top of each spar. The retaining string limits/defines the maximum movement of the spar
3. The springs are at the aft end of each spar (not really shown). They are custom made from piano wire and styled after Tim Van Milligan's flexi wing glider springs.
4. Everything is attached to the unpainted body tube "sleeve" that slides over the actual BT-60 rocket body. The whole mechanism is built around this sleeve which could completely slide off the rocket's BT if needed.
5. Two of three small wire squares/loops that stick out of the nose cone. The free ends of the spars are "hooked" into these wire loops and retained close to the BT during boost, but spring free once the NC ejects.

Concerning not tangling........ believe I had the best deployment luck placing the parachute below the streamers inside the BT. In this configuration, the ejection charge pushes out the parachute out (and the NC of course), which in turn pushes the streamers out. The spring action of the spars was not the streamer deployment mechanism. They snap open with authority and would rip the crepe paper streamers.

Not shown are two slightly elevated launch lugs (raised about 1/8 inch) needed for the launch rod to clear all the extra "stuff" on the body tube.

This rocket has not flown in a while (made back in 2012/2013) and I don't have any before/after on-board video examples that clearly demonstrate improvement in reducing recovery rotation. Viewing the ground level videos seems to show less rotation, however. As happens often....I think I moved on to other projects, but hope this helps. :)

Rainbow Fish.jpg
 

BigMacDaddy

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This rocket has not flown in a while (made back in 2012/2013) and I don't have any before/after on-board video examples that clearly demonstrate improvement in reducing recovery rotation. Viewing the ground level videos seems to show less rotation, however. As happens often....I think I moved on to other projects, but hope this helps. :)
Thank you so much - really appreciate the detailed description... I will definitely post videos is I get the Pelon rocket to work...
 
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