Poll: Metal In Rockets

[GL-P]

Is metal necessary in rocketry? I know the TRA regulations on this but I want to know the opinions out there.

 

[Johnnie]

I would rather have a 54mm T6061 rocket, where the motor has the rocket screwed to it. I would not mind having a 76mm one either...

But that will not be, when launches have large spectative crowds, and for obvious safety reasons these kinds of vehicles would not be allowed.

As for hardware, I have screws, all-thread rods, nuts bolts, washers...I use lots of metal in my rockets where I feel it is needed and helps out with strong construction...but it will only make up about 2% of the total rocket materials used.

...save the 54mm or the 76mm T6061 all aluminum rockets for BALLS...go extreme!

 

[Neil]

This has been a hot topic of debate between my dad and me for years... My dad argues that if a big rocket (say, 7" thru 16.5") hits you, your body is going to be a bloody pulp anyways, even if you made the whole thing out of nerf foam... You cant just have something like that come out of the sky and not do serious damage... rockets like the Estes Quark and Mosquito are dangerous if you think about it... I have had those things come screaming down within 20' of me at CMASS launches... If one of them landed dead on my head... Itd leave a bit of a mark (being sarcastic. I shudder to think what would happen, really...)... Now, if its a 7" rocket, your entire body is just going to crumple, nomatter what the heck its made of. You dont stand the chance.

So really, I dont see what the big metal/no metal fuss is about. If a rocket lawn-darts on your head, your dead, be it cardboard, metal, or fiberglass. You get buried with chunks of whatever its made of still in your body...


Sorry to be such a bright little ray of sunshine around here... But, really, if that huge Mosquito from LDRS landed on you, I dont think you would care WHAT its made of... Youd be dead anyways.

JMHO.

:kill:

 

[rstaff3]

For non-structural devices, all types of rocketry is OK.

For low power - no structural metal at all. There is no reason for it and we should keep the modroc world 'clean'

For mid power - don't see the reason but if you have a solo or non-sanctioned launch that allows it, OK. It's likely to be HPR launch anyway and I think I'm less worried about an aluminum MPR than a 100lb fiberglass rocket boring in from 1000 ft.

For high power - see above.

My opinions early, before morning coffee kicks in. Always follow the rules where they apply.

 

[Hospital_Rocket]

For motor cases, retaining mechanisims, and fasteners, have a good time.

Dick, I Iagree with you on LPR, except with respect to motor clips.

MPR same as LPR.

HPR/AR/EX - The usual Rocketry answer. It depends.

 

[rstaff3]

Originally posted by Hospital_Rocket

Dick, I Iagree with you on LPR, except with respect to motor clips.

Non-structural metal had been in LPR rockets forever and is fine. Motor clips, screw eyes, small lead weights, probably others that I missed.

 

[BlueNinja]

I don't use any metal in my rockets (so far) except for motor clips and on one of my rockets I attempted a weird retention system which didn't work, so I scrapped it.

 

[GL-P]

My dad argues that if a big rocket (say, 7" thru 16.5") hits you, your body is going to be a bloody pulp anyways, even if you made the whole thing out of nerf foam...

Agree, metal will just make your death a little quicker and less painful.

I saw that mosquito at LDRS after the launch. What happened to it? Would hate to see tumble recovery on that thing!

I believe rockets need metal for bolts, motor retention and electronics retention. I think structural metal in rockets is useless and way too heavy. I've seen advertising for a 38mm hybrid rocket but I don't know the motor classification is. It might really need the metal.

https://www.aeroconsystems.com/rockets/38special.htm

 

[Neil]

Drag seperation, I think... It ploughed into the ground about 50' from a line of cars and spectators... I think it came in on a drouge or very tangled/ripped/torn main or something... whatever happened, it'd sure hurt to have that sucker land on yer foot!

 

[Justin Horne]

Well, I just say it depends...

At a recent launch, a small estes rocket failed to eject and core sample at the feet of a spectator, who was horribly surprised.. Had it hit his head, im sure it would have done a little damage, but not death. I know my Arreaux, which can launch on an E, found do some damage if it hit you ballistic.

I think where it starts to not matter much is after a rocket wieghs > then about 6-7 pounds... Coming in ballistic, its gonna do damage, no matter what it's made of. the human head just is not strong enough when it comes to holding back a tiny projectile (nose-cone tip) If someone gave me a choice from being hit with a fiberglass cone or a plastic cone, id choose the plactic, but it might just be my last act of desperation...

 

[Stymye]

There should be a limit If the rocket is so big, mainly metal and could cause some serious damage , you could always do like the big boys and employ a remote seperation
to atleast keep it from coming in ballistic.

 

[Justin Horne]

That would be a good idea.. anything to stop it from being ballistic.. at that point, the rocket's well being isn't on many people's minds... I saw a Gates brothers's video of Porthos (was it one or two???) that separated. The chutes failed to come out, and it came crashing down hard.. Just as it hits you see a couple of kids running away from the impact zone, and were WAY too close for comfort....

 

[GL-P]

I saw that video too...

I saw a Gates brothers's video of Porthos (was it one or two???) that separated. The chutes failed to come out, and it came crashing down hard.. Just as it hits you see a couple of kids running away from the impact zone, and were WAY too close for comfort....

I have a heavily reinforced rocket that will hit 7000 feet. I figured it would be one dangerous rocket if it came in ballistic so I added backup apogee deployment avionics.

 

[Zippy]

I voted for "However a flyer wants to use it" and was quite supprised to see so many other people agreed.

In LPR there is very little need for metal and the rockets need to be light to perform with those puny BP motors anyway. Even the heaviest LPR could thwack me on the head and I doubt it would leave much of a dent. I have a hard head. Just as long as it didn't shoot my eye out.

In MPR we still need to watch the weight somewhat but there is plenty of metal in many. I wouldn't want to get thwacked on the head by any of my own MPR rockets, they would leave a dent. But thats what larger fields and questionable insurance are for.

In HPR some of the monster sized rockets use ridiculous amounts of metal and thats what deserts and questionable insurance are for. I don't think the amount of metal matters at all with really large rockets. Some might even see a weight savings by building entirely out of metal.

I think Neil's dad has it right although he exagerated it a bit. It's mass and speed that do the damage not material.

 

[Neil]

Well, im not sure if that really counts as exagerating...

Think about it... A 50 pound rocket coming in at just under mach one (as I assume it would, coming from in from over a mile), you dont stand a chance... Your dead nomatter what.

a really high-flying LPR can still pack quite a punch... coming in from way the heck up there at goodness-knows-what-speed...

*I* sure dont want to be the test subject to determine whether or not its safe to have a rocket lawn-dart on your head...

 

[Zippy]

Originally posted by Neil
Well, im not sure if that really counts as exagerating...

I didn't mean to slight your dad. Let's just say he's being colorfull when using Nerf foam as an example. After all I basically agree with what he's saying.

 

[DynaSoar]

Originally posted by GL-P
Is metal necessary in rocketry? I know the TRA regulations on this but I want to know the opinions out there.

The only materials that should ever be used in a rocket are those that are the best for the job. It's called engineering. And, of course, economically viable. That's called common sense.

I'd like to break CSXT's altitude record. I'd like to do it with carbon composite, but it may require aluminum and titanium instead. For everything else, there's Mastercard and the stuff it can buy from retail vendors, which is well proven to accomplish what it needs to. The answer depends on what you mean by "rocketry".

 

[Neil]

Well, the nerf foam was me... I was just repeating teh general idea...


But a hundred pounds of nerf foam going750FPS would still hurt...

 

[GL-P]

But a hundred pounds of nerf foam going750FPS would still hurt...

I should try that in low power!!! A nerf foam rocket with an E...

 

[Daedalus]

Originally posted by GL-P
I've seen advertising for a 38mm hybrid rocket but I don't know the motor classification is. It might really need the metal.

https://www.aeroconsystems.com/rockets/38special.htm

Sure does need it - all the metal is combustion chamber and nitrous tankage. The small payload section is carbon - the rest is motor. That's a real miniature sounding rocket

 

[GL-P]

Sure does need it - all the metal is combustion chamber and nitrous tankage. The small payload section is carbon - the rest is motor. That's a real miniature sounding rocket

Yeah, I saw it, drooled over it and realized it probably really needs all the metal. I wish I had $500

Has anyone ever seen one fly?

 

[bachsta]

what is the CSXT?

 

[rstaff3]

https://www.civilianspace.com/