Coolest L3 Project

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Chilly

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This is just great:

https://www.videorocketry.com/Joe/L3_Doc

For those who haven't seen it, he built a large-scale Mercury Redstone based on the GI Joe capsule...with GI Joe aboard, full-scale flight profile (escape tower jet, capsule chute recovery, etc).
I always thought something like this would be cool with a large-scale X=15, with R/C recovery.

WARNING: Post-flight crash investigation photos from flight 2e are gruesome, not for small children or the faint of heart.;)
 

dragonshiprider

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Really gonna have to look that site over.That's one very cool project.That impact looks awefully brutal.Ouch!Nothin' for Joe to lose his head over though!LOL!!!!!!! :D
 

Rocketmaniac

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Very Cool website..... That was a very "detailed" rocket.... I always wonder why people choose to make such complex rockets for a Cert attempt..... My L3 is going to be just a basic rocket, over built and on the heavy side.....
 

Todd Moore

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I always wonder why people choose to make such complex rockets for a Cert attempt.....
Why build a rocket that you don't want to build, just to do a cert flight?

Cert flights are free......

You can try a bunch of times! ;
 

DumasBro2

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I always wonder why people choose to make such complex rockets for a Cert attempt.....
Why not? Why not build something you want to build? If it fails it will also fail once your are certed anyhow. Some people may like the challenge.

steve
 

Elapid

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it is a shame that something like a foolish oversight and a total dependence on software for stability calculations were responsible for its destruction...

:(
 

cls

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Elapid, you were there, you must admit it was a spectacular crash!! just glad noone was hurt, etc.

what (non-software) test would you do on a rocket that large, to determine stability or at least CP?


by the way I hope folks take the time to poke around the videorocketry web site. Jamie has a lot of neat stuff there. in particular, "Gumby's Space Adventure" has been really inspirational for us. it got us started on video cameras, Crayon rockets, which led to level 1, etc.
 

Todd Moore

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Originally posted by GL-P
but the rockets aren't....

K.I.S.S.
Question;

Was it your money? ;)

K.I.S.S. has always seemed like a GREAT Acronym.....





For stupid people :D

Sorry.. Couldn't help it.

But seriously. This rocket could have JUST as easily crashed if it was the flight right after a successful big-dumb-rocket L3 flight. Cert flights are free. Don't listen to people when they try to tell you to build x,y or z rocket for your cert flight. Build the rocket YOU want to build. If you do it right, you'll succeed. And there is no shame in failing. I've seen many BDR rockets fail too.
 

Elapid

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spectacular, yes... scary... i'd say so.
that rocket could have gone anywhere...it was lucky it didn't choose the flight line.

a simple glance at the rocksim file will tell you it's not stable. there was 5" between the CG and CP with the M motor loaded. the body diameter was around 10"... unfortunately, rocksim uset the 0.5" tower diameter to calculate caliber of stability and reported it at over 10 calibers of stability.

anyone paying attention to the data SHOULD have caught that little detail. 10 calibers of stability, 10" rocket, better be 100 inches between cg and cp.

that the rocket made it past the cert team worries me.

the NAR requires manual calculation of the CG and CP for the L3 cert from what i can determine, so these types of *accidents* should be less likely to happen.
 

Chilly

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That's interesting...not that I'll be doing L3 anytime soon. I would think that you wouldn't want to rely on RocSim alone for a big deal like a Level 3 flight. Heck, I don't fly anything without physically finding the CG with a balance test. Seems to me even a big L3 project could be balanced over a sawhorse or something.
 

FredA

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I agree - I'm surprised (and dissapointed) that this passed the TAPs.

But I disagree that Cert flights are free....especially L3 certs.
Your TAPs should have a fair amount of involvment leading up to your flight - this is only free from a monetary standpoint.

Agreed you can try as many times as you like and can afford, but everyone involved should be working to get it done right the first time.
 

DumasBro2

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So, where are any additional costs incurred on an L3 cert flight that aren't there once you are certed?

steve
 

FredA

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How about having your TAP give up a weekend and drive 9 hours round trip to witness a failure. The do it over and over again.

How about the time (most L3 attempts) spent farting around on the pad - tying up the launch site?

I said non-monetary cost.
You are soaking up other peoples time - don't waste it.

Certs are all about DEMONSTRATING PROFICIENCY at a new level.

Certs are not (should not be) a "let's try and see" approach.

Now - I don't want to paint Jamie in this light - I'm talking in a generic sense.
 

DumasBro2

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We’re not talking about a try it and see approach. We’re talking about build what you want for your L3 attempt, not just a 3FNC rocket. The TAP should be in the loop though the building process anyhow. I would not think a Redstone would be out of line for a cert attempt even with all the bells and whistles. If it were the TAP could have suggested a less complex recovery, but this wasn’t the failure point. If being a TAP is too time consuming and a hassle maybe it’s time to hand in the merit badge.

steve
 

Rich Pitzeruse

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I know someone who wants me to be his L3CC for a L3 cert using a Saturn 1B. This person has alot of L2 experience, and alot of scale model experience. For the life of me, I can't see what he would gain by doing a L3 cert flight on a simple 3FNC rocket, that would then help him be more successful at flying an M powered Saturn 1B.

-Rich
 

aksarben10

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Originally posted by freda

Certs are all about DEMONSTRATING PROFICIENCY at a new level.


Sort of not really. Moving up to a new cert level is showing that you have learned enough from prior flights to apply it to a new level. In order to demonstrate proficiency you would have to do it over and over not just once.

There is nothing wrong with trying something new on a cert flight, IMHO. Not everyone comes at certs from the same point of view some want that simple shot to get the cert and others feel confident that they can do that and need something that will challenge them further.

L3 is different then any other due to the cost and TAP requirements. Not everyone plans on flying L3 much if every after the L3 cert flight mainly due to the cost to fly at this level. I am currently planning my L3 mainly for the challenge not so that I can fly M-O motors; I may never fly another M again. I can’t afford it and it took me a year to save for this motor and I would rather fly more with smaller motors.

Most L3 flights are done at large launches like LDRS and other large regional launches so the inconvenience to the TAP member is much less then if they were coming to a distant launch for nothing else. I would also think that they may like the variety in a complex project then a simple 3FNC model. I do not know about this but I will ask my TAP member what his feelings are on this subject, I am curios. Also the TAP members have the ability to nix the launch or the design if they feel that it will not work, so they do have some input into the design.

Scott
 

FredA

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Certs are about demonstrating that you are qualified to fly the next bigger range of motors.....

They are not meant to be merit badges, hoops to jump through or anything else.

Maybe they are viewed that way by some people, but that is not the intent.

Certs are your license, so to speak, to fly whatever you want (provided it gets past the LCO) with the next larger class of motor because you have demonstrated that you know what you are doing.

How and why you do this is between you and your TAP of L3CC.

What I'm responding to is the notion that Certs are FREE.
Anytime you involve other people that are there to help you, acting like there time is free seems down right rude.

Just my opinion.....
FredA
 

DumasBro2

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I’m involved with many organizations (aside from rocketry) including youth baseball and football. I do not do this to be call “coach”, “president”, or whatever else. If a project fails or team isn’t successful on the field is it a waste of my time? Never. It’s something I enjoy doing. I can never payback what people have done for me I can only pay forward.

steve
 

aksarben10

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Well I agree with you that they are not free it takes a lot of your time as well as others, your TAP and others included.

That said, I do not think that a complex project means that they person has not put due diligence into it. I also do not think that complex projects should be eliminated from a cert attempt only because they are complex.

The Mercury project looks like he has put lots of effort, though and time into making it a success. I do not think that he has taken peoples time for granted.


As too merit badges and certs. I believe that certs are a merit badge, what else is a merit badge other then something that shows you have learned enough to move on and that you have demonstrated the requisite knowledge in a certain area along with creating a goal to work towards.

This is an excerpt from the Scouting.org site about the purpose of merit badges "a Scout acquires the kind of self-confidence that comes only from overcoming obstacles to achieve a goal"
Sounds similar to what we use certs for.

I think I know what you are trying to get at. You do not want the whole cert process trivialized and reduced to the only goals in rocketry. This is what I think that some people do. Some people view certs as the only goals in rocketry and miss the whole point. There are many goals in rocketry other then can a build a bigger rocket. I personally find challenges in EX and I am enjoying clustering Estes motors quite a bit, I also like finless models such as spools, cones and pyramids. There is a lot to rocketry other then just getting the next cert.


Scott
 

FredA

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No argument there - thats why its a hobby.
With only one TAP in Oregon and only one in Washington these generous people can get busy. Maybe they are going to the launch anyway - but don't assume. At our last launch, a TAP and a L3CC attended for the soul purpose of witnessing L3 attempts. Both of these people made the drive to help somebody else.

Sure they are there because they love the hobby and want to help people. But they also know that in order to members to advance their time is required. There is an old saying, Time is Money.

All I saying is that if your attitude is that you can attempt to cert as many times as you like, you are probably abusing your TAP's (or L3CC) good will.

Sure, they can refuse, but why get to that point.

Enough on this thread.....
Just take your cert's seriously....
 

cls

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This is an excerpt from the Scouting.org site "a Scout acquires the kind of self-confidence that comes only from overcoming obstacles to achieve a goal"
I think this hits the nail right on the head: how do you learn anything without making mistakes? it's natural, that's the way humans work. doubtless all current HPR best practices come from mistakes others have made.

certainly we can all learn a few things from this failed flight, cert or not is irrelevent.

for me, first is, always check & recheck CP & CG, a few different ways.

second is, now we know one more idiosyncracy of rocksim, which has gone unnoticed for years and may have gone on longer, resulting in perhaps a few lost rockets and head scratching. but, now it's clearly documented and we know how to work around it.

third is, when the LCO calls heads' up - pay attention!

fourth is, don't be afraid to reach for a goal.
 
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