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Stewart32

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Well...

I wanted to launch a few rockets late Sunday. So I gathered up the boy, some old favorites, and some new rockets, and loaded up the car. As a bonus the wife, uncharacteristicly decided to join us. We headed to our favorite lauch site, MSP.

Perhaps the heat and humidity fogged my judgement but for some reason I set up adjacent to an active soccer game, I was in a hurry as daylite was fadding. First two mistakes.

The first launch was the venerable Fat Boy (naked) modified for 24 mm power, a D12-5. This was a maiden voyage and my first D impulse launch, and in hindsight the anticipation was part of the poor judgement. The rocket immediately went horizontal upon reaching the end of the Estes 1/8" rod and pad. Luckily this was 180 degrees opposite the soccer playing field. It made for an impressive, but safety unacceptable flight. This was followed by oos and ahs (or explicatives?) from some of the game spectators who were chokeing on spent BP fumes.

Murphy wispered; I swatted at a mosquitoe pestering my ear.

While the boy (and wife) retrieved the Fat Boy, I prepared a Custom Fiesta with a B6-4. The wind was against me toward the playing field. I made appropriate adjustments to the rod.
The lauch went well with all events occuring as expected. Upon ejection the rocket began to drift across the roadway precariously close to the now ending soccer game. I did my best to dodge traffic while tracking the desent. The rocket touched down about 4 inches from a green 55 gallon drum now park trash can. Another omen?

Now the thrid and final shot...a cluster of 3xC6-7s in a Cycline 3 Fun Fat Rocket. At this point Murphy is pleading caution but of course the voice of reason falls on deaf ears for some reason. This rocket was built according to specification and had been lauched several times without incident. 5, 4, 3, 2, 1 launch.....Up untill this point I had only read stories about rockets looping end over end traveling wildy out of control, but had never witnessed the strangely mezmerizing phenomenon first hand.
With three motors a blazing the rocket looped about three times, 15 feet off the ground. It finally came to rest about 20 feet from the pad having missed pedestrians and vehicles. It crashed about 5 feet from the rear of one of Lexington's finest officers parked in a cruiser. Pop Pop Pop. Three ejection charges later and I am formulating an explenation while approaching the good officer who is stepping out of her now smoke filled cruiser (her window was open). I really had no explenation for this compleatly unexpected behavior and was truely at a loss.
Her advice: "You have the whole park, go lauch somwhere else away from people."
Sheepish response: "Yes M'am, you are correct. I think we will call it a day."

Luckily nobody was injured in this comedy of errors, poor judgment, and failed common sense. So, it is with chagrin that I appologize to my fellow rocketry enthusiasts. Having learned my lesson. I vow to avoid stupidity in the future in as much as possible and heed Murphey.

Post mortem:
The Fat Boy having been modified probably needs nose weight to get the CP behind the CG again.

The cluster rocket was built according to specification. Why it went squirlly, I can only conjecture. I did notice that the launch rod was in two pieces following the shot. I think that the rocket dragged the upper portion of the rod with it for a short distance into the air...while starting the shot on an unstable trajectory. But this has never happend with any other countless shots from the same equipment. The only other reasonable expleantion is that the rocket was made unstable from the added wieght of the C motors. I think I had only flown on B prior to this fiasco.
 

powderburner

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Originally posted by Stewart32
Her advice: "You have the whole park, go lauch somwhere else away from people."
Really pretty funny after the fact, but you are lucky you didn't actually HIT her car. We would have to start a thread here on TRF to collect bail money?

Sorry to hear of the mayhem and madness. Sounds like you have already identified a major part of the problem: that piece-o-junk Estes launch rod. I have refused to use those things since I was a kid because of the exact same problems that you had (snags, bends, breaks). Spend the whopping $2 and go get a four-foot piece of 1/8 diam round rod at the home improvement store, or the three-foot long tempered steel 'music wire' at the hobby shop.

You can keep that two-piece Estes rod in your range box to use as a tool for pushing used motors out of long rockets.
 

Micromeister

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Yep:
Never launch any model over a C6 on an 1/8" rod of anykind. 3/16" minimum, 1/4" is even better...especially for clusters.

While I really do not like reading about anyones misfortune at ANY launch...this one seemed to be doomed from the start. I'm turly sorry poor judgement caused some damage to your models..But the story tells me your NOT following the Model rocket safety code!
Never ever attempt to launch an untested model around a crowd of people. it's just NOT done...It's also a good idea to follow this rule with clusters as there are any number of things that can go wrong during there igintion.
That modified big daddy could have been a reason for NO one to every be able to launch from your park again... When in doubt, DO NOT launch. I find is prudent to try my best to launch as far away from non-participants as possible. This wasn't murphy at all, If anything he may have helped you out...Lets try to use a little more though next time. At the very least you'd have ticked off the coach for distracting his players. We all do silly things once in a while..Hope this one cured your GO fever;) Haste does indeed make waste. ....Please Safety First.
This isn't ment as a harsh post, but we need to remind our younger readers, there really is a reason for following the safety code. and stay a far away for other as we can.
 

Bowhunter

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I agree with micro never use a 1/8 rod on somthing like that I learned the hard way with my 4-18mm fatboy to much rod wip then I went to a 1/4 rod and I couldnt of asked for more of a pretty flight
 

rabidsheeep

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did the same thing with my fatboy... it is a wild flight though :D

you win some, you lose alot of em..
 

shockwaveriderz

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wow jack..trying to end model rocketry as we know it in lexington MSP before I even get up there? thanks alot ! :) My suggestion is to NOT use the small field next to the soccer fields.....instead, go around the corner, across from the dog park and set up in that much larger field......

I betca those 3 ejection charges going off scared the poop outa that policeperson........heheheheheh


Was this the same cluster model you launched down here with both B's and C's and it flew straight up ? hmmmmm
 

Planet Andy

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Well,

Seems Stewart has learned a thing or two or a cluster of three. I would have to say though that when some of us get that launch bug sometimes logic and common sense fall by the wayside. It's tough to stand down. I had last week vacation and only got to launch 3 vehicles. When the winds were right, all my favorite fields were being used for Football practice. I did get out when I knew winds were wrong and I lost a Chrome Dome. I specifically brought the CD out cause I had no attachment to the 10 minutes it took to assemble it. Still, I left the field thinking that was a little senseless and a waste. It's the first treed rocket that I actually can see in the tree so I'll be reminded each time I go to the field. I thought about climbing the tree when it first happened to retreive it about 50 ft. up then realized I'm going on 43 not 13.

cheers,

Andy
 

Fore Check

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I've had no problem launching a 2 x C6 cluster (in my Deuce) and a number of D and E powered rockets on a 1/8" rod.... No trouble whatsoever. Does this make me lucky?
 

Stewart32

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Yes Shockie,

Does your log show a 3XC flight?


tail between my legs........
 

rstaff3

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My 2cents on the rod: it d'pends. As a general rule across the board I agree with Micro. I fly saucers, dice and cones off smaller rods on D and E motors just fine. Many regular D rockets work fine on the smaller rods, kinda depends on the weight and how stable they are and whether they are flight proven. E's need the larger rods. Like I said, my 2 cents.

Especially in a crowd, err on the side of caution. Even more so if the people around are not a part of the launch. If you can get everyone in the area to get on their feet and pay attention is one thing. Casual passers by who are'nt paying attention are yet another issue.
 

OARJeepr

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This is one reason why club launches are so nice. There is almost always a voice of reason somewhere in the crowd. You'd have never set up next to a soccer match and you'd have plenty of help tracking your rockets. You also get to see a bunch of other rockets launch without having to spend any money on them.
 

astrowolf67

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Stewart,
My 24mm Fat Boy, which I flew at the last Etown launch on an F21 Econojet, has 2 3/4 ounces of nose weight in it. It's been flown on D12's, E9's, E11's, and F21's with no problems. I also use a 1/4" lug on it, rather than a 1/8 or 3/16.
 

Elapid

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and you learned something...

sounds like a successful launch day!
;)

better luck next time!
 
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