Parachute Questions

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11bravo

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Category 1: Materials- Anyone use either Nomex or Kevlar parachutes and just not have to worry about wadding, pistons, or baffles?

Category 2: Guidance- Is the "no guidance" thing a law or regulation (either of these being governmental in origin) or just a rule some whiz-bang rocket scientist came up with for the national organizations?
Would a radio controlled, guided parachute be considered covered by this law/regulation/rule?
For the inspiration behind the guided parachute idea, see-
https://www.paraflite.com/html/delivery.html
Specifically, see the link under the bottom picture "5000 lb Precision Guided Aerial Delivery System" and have a look at the movie clip to which it points.
I'm sure that a person could come up with a small, steerable parafoil and an RC setup to accomplish this.
Be for bigger rockets, but sure would be nice to guide the thing to a landing next to your lawn chair. :D
Waddya'll think?

Greg
 

DynaSoar

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Originally posted by 11Bravo
Category 1: Materials- Anyone use either Nomex or Kevlar parachutes and just not have to worry about wadding, pistons, or baffles?

Category 2: Guidance- Is the "no guidance" thing a law or regulation (either of these being governmental in origin) or just a rule some whiz-bang rocket scientist came up with for the national organizations?
Would a radio controlled, guided parachute be considered covered by this law/regulation/rule?
For the inspiration behind the guided parachute idea, see-
https://www.paraflite.com/html/delivery.html
Specifically, see the link under the bottom picture "5000 lb Precision Guided Aerial Delivery System" and have a look at the movie clip to which it points.
I'm sure that a person could come up with a small, steerable parafoil and an RC setup to accomplish this.
Be for bigger rockets, but sure would be nice to guide the thing to a landing next to your lawn chair. :D
Waddya'll think?

Greg
1. Never heard of such a beast. The things I've gotten made of that stuff are pretty loose weave. They wouldn't make good chutes except for large sized, and then somewhat inefficient.

2. There is definitely no rule, regulation or law against guidance in rockets either ascending or descending. None. Not from any rocket organization, government agency, or professional safety/security/alien-presence-monitoring organization. There may have been something relating to guidance, possibly in NFPA 1127 (someone suggested that as a possibility) but there is none now anywhere that I can find or that anyone will point out to me. There are still people who claim there is. This flies in the face of at least one NARAM R&D project which used guidance as a "sun seeker", not to mention the obvious R/C controlled boost gliders. What there is, is many people who immediately jump to the conclusion that any attempt to do anything remotely (no pun intended) like guidance will be intercepted and investigated by the government, who, like the people who're having these imaginings, will conclude that anything "guided" will be used against a hard target, and so They Will Come Down Harder On Us Than They Have Already. (Note to mods: this is not a political statement, but rather one of observation of peoples' reactions to this topic. I have a political stance on this, a rather vehement one, but that's irrelevant to these observations). See the rec.model.rockets thread "Subject: Where does this "No Guidance" stuff come from?" for my asking the same question, and getting material supporting the above observations, more noise than signal, and one reasonable but vague suggested possibility for the origin of this rocketry urban myth. Also included is a lengthy rant by me regarding this topic, peoples reactions to it, and more politically oriented foot stomping than anyone should be allowed to enjoy. And I did. And that pretty much ended the thread.

I've also tried emailing people associated with a prominent rocketry related web site that makes this statement, asking them where this comes from and if they have a reference, past or present, but never received an answer.

Go ahead and use active, passive, internal or external guidance on anything going up, coming down or arcing over apogee. If anyone, from common civilian to Men In Black, has a problem with that, feel free to make them aware the problem is theirs. Before, I only wanted to develop some guidance systems out of scientific interest. Now I'm darn certain to do so just so I can give some people aneurysms by telling them all about it in public.

Orbital mind control lasers. That's the only way to explain it. And obviously my tin foil helment has so far protected me from having this anti-guidance thing implanted in my brain.

I'll stop and go take my meds now.
 

powderburner

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I am not so sure about Dynasoar's answer to #2, although I cannot retrieve and display a specific official NAR statement regarding this. About the closest I can come at the moment is a sloppy interpretation of NAR safety code item #8 (Flight Safety: I will not launch my rocket at targets, into clouds, or near airplanes, and will not put any flammable or explosive payload in my rocket). And this does not directly address the specific subject of onboard guidance, it only hints at it indirectly as a prohibited means of hitting a target with a model rocket.

This is probably a subject that needs an update from some official NAR and/or Tripoli committee. Back in the olden days, the whole idea of onboard guidance was a joke, because a working set of home-made electronics (and power supply) would have weighed about as much as my car. Modern technology is smashing through that barrier (like an RC airplane with a TOTAL weight of 1.54 grams) and will likely soon make it possible to add some fashion of guidance or control system to even low-power rockets. I think we need some clear guidance here, in written-down form that everyone else can point to, that unambiguously defines what is acceptable.

11Bravo, I think your paraglider controller idea is brilliant. Let me go one step further: could you rig a low-power radio transmitter that could be set up near the pad, and give the onboard rocket electronics the capability to detect and steer toward the transmitter (yes, the height of laziness, I wouldn't even have to do any steering!)
 

Stymye

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is a model/hpr/hpr lite, rocket qualified as a suborbital launch vehicle?

heres the definition,

Suborbital missions involve a launch from Earth in which the launch vehicle rises to a maximum altitude and then falls back to the planet. Any launch that doesn't reach orbit or escape the Earth's gravity is a suborbital launch--

now add guidance and it becomes a,
Guided suborbital Launch vehicle.
and the rules and criteria for that would easily fill this page.

I also recall reading something about the fact that you can't "turn off "a rocket once it's launched, (compared to an r/c plane or r/c glider) so the rc glider comment would be moot

there is also a reference to maximum "burn time" there is a limit
mentioned somewhere(I wish I could find it again)mabey someone else can clear that up

I'm posting most of this from my vague memory of things I have read online in various gov documents..so take it with a grain of salt...
but I believe this is where some of the controversy stems from
 

DynaSoar

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Originally posted by powderburner
I think we need some clear guidance here, in written-down form that everyone else can point to, that unambiguously defines what is acceptable.
That's an impossible task. A exhaustive listing of posibilities allowed would be too big to read, and creating the list, which would (one would hope!) include justifications for each, at least in the creation, would take forever.

Asking the same piece by piece is the same problem, only driven by request instead of by prior consideration.

What's needed is a listing, with justification, of what's forbidden. This is possible for the regulators, and protects the regulated from being forbidden the useful or neutral just because someone can find a negative use/abuse for it. Someone will always be able to find a negative use for anything.

Regulating "just in case" is bad. It is the basis of the present problems we have with BATF. Allowing it to happen is worse to my mind, because it means giving up having the final say as participants in a democracy, which includes our own rocketry self-regulatory bodies. It has become much more difficult in the last three years to hang onto this. That concerns me far more that whether someone cares if I drive my rocket or let it fly ballistic.

"I will not launch my rockets at targets" covers peoples' concerns on this matter. I am certain that "targets" was never intended to mean a point in mid-air directly above the launch pad, and so (frinstance) a rocket with gyroscopic driven servo'ed fins to keep it vertical against weathercocking, in order to get maximum altitude or placement for spot landing, is not what they intended to forbid.

Forbidding everything to prevent the abuses is also a waste of time. The bad guys are going to do bad things no matter how much of it is formally classified as bad things.

I'm pretty sure the NAR and TRA BODs would agree with this, since they're already fighting this fight on a different topic on our behalf against BATF. They might agree with operating regulations, such as proving your ability to safely operate and control such a craft, much as they do with HPR. I'd be in full agreement with that.
 

DynaSoar

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Originally posted by 11Bravo
I'm sure that a person could come up with a small, steerable parafoil and an RC setup to accomplish this.
For a paraglider or rogallo wing, you could steer its descent with a single +/- channel by shortening or lengthening one rear corner shroud. More complex arrangements would give you more flexibility, but one would do the job.

Less directed but also doable, would be a controlled reef on a chute. When it deploys it has a high reefing collar, preventing full opening and allowing more vertical descent. When you push a button, the collar gets pulled down to the bird, allowing full opening. The result is like dual deployment. Less drift.
 

11bravo

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Originally posted by powderburner
snip a BUNCH...Let me go one step further: could you rig a low-power radio transmitter that could be set up near the pad, and give the onboard rocket electronics the capability to detect and steer toward the transmitter (yes, the height of laziness, I wouldn't even have to do any steering!)
We also considered using an onboard GPS and having it fly to a predetermined point. IIRC, the Guided Aerial Delivery System I mentioned in the original post can either be R/C'd or preprogrammed to use GPS.

Greg
 

xenon

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Originally posted by stymye
[B

there is also a reference to maximum "burn time" there is a limit
mentioned somewhere(I wish I could find it again)mabey someone else can clear that up

[/B]
Yes, I can't remember where I saw it either, but it is 15 seconds unless it is a Tripoli launch, where it can be up to 60 seconds.

Also, the rocket must weigh less than 12 lbs per 1 square inch of frontal surface area. So if you have a 3 inch rocket that weighs over 84.8 pounds, you need a Launch License to fly it
 

DynaSoar

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Originally posted by xenon
Yes, I can't remember where I saw it either, but it is 15 seconds unless it is a Tripoli launch, where it can be up to 60 seconds.

Also, the rocket must weigh less than 12 lbs per 1 square inch of frontal surface area. So if you have a 3 inch rocket that weighs over 84.8 pounds, you need a Launch License to fly it
I can't find the 15 second rule in the NAR LPR or HPR codes, or in the regular or EX Tripoli codes.

It's not in the FAA regs, so if it's anywhere it's in NFPA 1122 or 1127. Does anyone have these available to quote the section?

I also can't find that 12 lbs/sq. in. thing anywhere. I've never heard of it. Where's it from?
 

xenon

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It's not in the FAA regs, so if it's anywhere it's in NFPA 1122 or 1127. Does anyone have these available to quote the section?

I also can't find that 12 lbs/sq. in. thing anywhere. I've never heard of it. Where's it from?
"14 C.F.R. Ch III 401.5.b Amateur Rocket:
1.Launch from a private site;

2.Has a motor, or combination of motors, with a total impulse of 200,000 pound-seconds or less;

3.Has a motor, or combination of motors, with a total burning time or operating time of less than 15 seconds (see exception below); and

4.Has a ballistic coefficient (i.e., gross weight in pounds divided by the frontal area of the rocket vehicle) less than 12 pounds per square inch.

(AST memo adds) Additionally, if a launch is to take place at a Tripoli Rocket Association-sanctioned event, the 15-second burn time provision does not apply. Such launches may involve rockets that have a motor, or combination of motors, that have a total burning time or operating time of up to 60 seconds."

taken from
https://www.seanet.com/~ssstolt/regs/faaregs.htm

I think I first saw it in John Wickman's How to Make Amature rockets.

I'm sure more searching would lead to more info
 

Stymye

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Dynasaur, mainly FAA regs,they control the airspace.
 

DynaSoar

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Originally posted by xenon
"14 C.F.R. Ch III 401.5.b Amateur Rocket:
.....
taken from
https://www.seanet.com/~ssstolt/regs/faaregs.htm

I think I first saw it in John Wickman's How to Make Amature rockets.

I'm sure more searching would lead to more info
Found it. Since the CFR pages moved, the link from from NAR's HPR safety code leads to the CFR main page and you can navigate down through all of them.

Thank you.

I find it real hard to believe, though, that if I were to two-stage a pair of AT I65's and fly them on my own property, the Office of Commercial Space Transportaion would know what to do if I called and asked for permission. In fact, I think I'll call and ask.
 

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