Recovery attachment options to hold body horizontal during descent?

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Charles_McG

Ciderwright
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I'm pondering rigging my current build (300% NASA Pegasus Estes 1376) to descend with the tube near horizontal to change the landing load on those big swept back fins.

I have some ideas for sheltering an external line during boost - but am still working on how to attach an aft line to the main chute line and (especially) get it under the tubing at the break point without weakening the tube.

My searches of the forum haven't yielded anything, so I'm asking for ideas.
 
I think to get a flat landing you will need a really lightweight body and a fairly small chute so that the load is balanced out. However, I think this is a "I hope this will work" instead of a "yup, definitely will work". Without a few drop tests, it's hard to know what those fins will do when falling.

To be honest, I would solve this problem by having a really oversized chute to make sure that it has a light descent. This is what I do on my Apogee Snarky to make sure it comes in safely. Now damage from younger rocket retrievers is a whole 'nuther story.
 
The Pemberton Bucky Jones has you make a small hole on the vertical tail and tie a Kevlar cord to it.
The cord runs outside the body and tucks in with the nosecone. The other end is secured inside the main tube
There is a knot tied on this cord that he chute attaches to. I believe the knot is about a third of the way down (but that could be adjusted)

When the ejection charge goes off, the nose cone comes out and frees the cord. The cord now runs from the rear tail to the front with the chute in "middle" bringing the main rocket down in a horizontal position.

I'm at work now but I can get a picture later tonight
 
If you run a line from fore to aft with the chute (or drogue-chute chain) in the middle, how can it not come down flat. I’m thinking of the Saturn IVB-LM transition-CSM for both the Saturn V and Saturn1B, or the capsule on the Mercury Redstone and Mercury Atlas kits.

Now, if you’re arguing that the orientation won’t matter nearly as much as the force, for this particular design, I’ve wondered about that, too. There are always bigger chutes. And it would simplify the build a bunch.
 
If you run a line from fore to aft with the chute (or drogue-chute chain) in the middle, how can it not come down flat.

I could see this working, but then now you have two potential spots for zippering to happen. Also, I'm thinking that if you have a large ejection force pushing the chute out the front, you could have an asymmetrical load on the fore/aft connections where there's slack on the fore end, and taut connection on the aft. This would figure itself out, but for a split second, it could cause trouble.

Another issue is having a line running fore to aft would have a potential to tangle on the fins.

Then again, I'm not a parachute surgeon.
 
I've seen it done on standard dual deploy rockets, but never got close enough to see how the rigging was done. For my 4" Redstone capsule, I cut a groove in the shoulder of the capsule to let the cord go down through the body tube. But this is all theory, since I've never launched it... :eyeroll:
 
I've seen it done on standard dual deploy rockets, but never got close enough to see how the rigging was done. For my 4" Redstone capsule, I cut a groove in the shoulder of the capsule to let the cord go down through the body tube. But this is all theory, since I've never launched it... :eyeroll:

I remember a couple of Centuri (LPR) kits with horizontal chute recovery:

SR-71, for example:
https://www.spacemodeling.org/jimz/cen5349.htm

Space Shuttle Columbia, can't find the plans, but the catalog picture shows a shock cord line tied through launch lugs around the root of the vertical fin, it runs external and into the main body at the cone.
https://www.ninfinger.org/rockets/nostalgia/80cen002.html

Thanks for the suggestions. The SR-71 is most like what I have in mind. It's easy to do on little kits - shroud line doesn't bind up between shoulder and nosecone too badly. But going bigger??? I've thought about that 'groove' in shoulder option - I just don't like the idea much.
 
I did this many years ago with my Estes Ranger. I punched a hole through one of the fins (or two I can't remember), ran fishing line through the hole and extended up the front of the body tube into the parachute compartment. I had one chute for the payload compartment and one for the booster. The booster came down relatively horizontal. A piece of fishing line on the outside of the booster was not too obvious, it would be harder to hide some tubular nylon on the outside of a larger rocket.
 
Few thoughts

With that design, unless you have rear end ejection or you use an external rear attachment and land nose end of body tube first, you are going to have the first rocket-earth impact be a fin, even if recovery is horizontal.

Not sure having the front of the body tube bear the brunt of the impact is all that great an idea either, although you could reinforce it.

If you put a single attachment point on the ventral side of your rocket a bit forward of the POST DEPLOYMENT CG (with nose cone and chute out and with expended motor in place) the rocket SHOULD descend horizontal, as the tail feathers will cause more drag than the barren forward end. Given a ventral attachment point and what appear to be wider spread of the ventral fins compared to dorsal fins, Rocket should fall horizontal with dorsal side down, so those two fins on top are going to hit first, which may also not be good.

Got something like this with descent of TBolt rocket

https://www.rocketryforum.com/showt...(think-C-141)-Kevlar-Failure&highlight=T-bolt

May sound crazy, but any chance you can extend your motor out further back, so it extends well BEHIND the furthest back fins, deploy a good size chute in standard fashion so rocket body descends tail first, so that your motor takes the initial impact? Obviously you will need to adjust nose weight to maintain stability.

Cool project, hope you get some great flights out of her.

Tom
 
Final idea.

Place 2 or 4 plastic rods (maybe plastic chopsticks?) or wooden dowels at the pod/Main tube, at the main tube, about one fourth inch diameter, project back 8 inches or so . Tails ends are rounded for safety. Paint them black so they are relatively invisible. Standard chute deployment, rocket comes down tail first. These are your first point of impact. Maybe make them easily replaceable so if they do break, you just put new ones on for next flight.

Main idea is to have your initial rocket to earth contact point be unbreakable or easily replaceable.
 
When you suggested mounting the motor back further, I thought of putting rear extensions in the outboard motor mounts if I wasn’t putting motors in them. Just BT50 tubing.

Thanks for the thoughts.
 
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