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Landshark Ahoy!

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o1d_dude

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My most “exciting” rocketry experience occurred about two years ago at a LUNAR launch and involved a land shark event.

I was talking with Thirsty Barbarian and the Atteberry family. We were standing in the spectator area behind the range head tape near the southern most Low Power pads...well outside the minimum safe distance...and even paying attention.

An E9 Death Race entry chuffed off the pad to about 6’ of altitude, went horizontal, and then the E9 caught...passing first between Thirsty and I, then past Chris and wife, and between the kids, ultimately pegging into the dirt about 30’ beyond where we were standing.

I always wondered if a model rocket coming straight at me would look like an RPG. I now have a pretty good idea (it’s smaller). Also my bobbing and weaving skills are acceptably intact for a geezer...I dodged the landshark.

Sorry, no pictures. We were all rather busy while this was happening.
 

mo2872

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Closest I’ve come so far to a land shark was with the full Estes Shuttle. Launch started well, went up 25’ or so, then rolled and went horizontal. Made it about 300’ down range before finishing the arching trajectory right into terra firma. No dodging required, but it did destroy the thin abs shuttle. Remarkably, the boosters and tank were just dirty.
 

Steven

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As a kid in the 70's I had built and flown a Centuri Long Tom out in a huge vacant dirt lot in Phoenix with my dad. The first flight went without a hitch. Upon trying to load the parachute for the second flight the nose cone wouldn't fit properly. I couldn't determine if any lines or cord were responsible so I shoved the cone on and proceeded with the launch. It wasn't far from the back of my mind that this might not have been the best approach with a tight nose cone but I was damned if I wasn't going to launch it either.
Up it went.........and I began to slowly realize that it was taking too long for a sighting of any kind based upon the first flight. As the seconds ticked by it became more evident that the parachute never deployed. Now I got really spooked. Where does one run and hide from an incoming lawn dart? And then it happened. First I heard an unmistakable whistle and in the blink of an eye I saw it bury itself into the dirt roughly 25 ft. away from us. One of those sphincter moments you don't forget. Never did that again.
 

cerving

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Had a 3x24mm BT60 Titan-III sort of cluster with two outboard F24's and a central airstarted F39, at one launch one of the outboard F24's decided not to come up to pressure for awhile. It did a few tight loops before plowing into the ground, breaking off the pods... when the latent F24 decided to light. It probably scooted about 200', fortunately away from the flight line. The central F39 never lit... the altitude@time qualifier in the Quantum did its job. Wish I had a video... it was very exciting.
 

GalantVR41062

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The old Sportscoach motor home my parents had for a long while was dubbed "Land Shark".

I have seen some horizontal flights, my first mpr scratch build made it up 100' went horizontal about 100' then arked up again 100'.
~John
 

jd2cylman

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Watch out, they bite hard sometimes...

Well, poop. They didn't load in the right order...
But you get the point (or top of a Stealth, in this case...).
 

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ksaves2

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Worst chuff launch I ever saw was at the old, now defunct Peoria Area Rocketry Society launch in the olden Ex/Research days. The Research rules were in flux at the time but the prefecture followed them to a “T”. They were stupid strict. No kidding, I rushed my L2 so I could get it and still be able to launch “certified” motors at a Tripoli Research launch. Those were idiotic rules back then. NAR was worse though don’t slam me as I’m a member with them too. Gave me my old membership number back when I asked for it from when I was a kid! Kinda cool and I still maintain it.

A guy came down from the Chicago area with a relatively small rocket with a 54mm research motor in it. Thank heavens, our early launches were not well attended!

Well in the old Metamora launchsite, we’d stick the HPR pads “way the heck“ out there so if anyone showed up with an
“M” motor, we’d be kosher with the rules.

Anywho, this guy sticks this what looks like a minimum, bare not painted, diameter fiberglassed “reinforced” rocket on the pad and gets it ready. Our prefect, Pat Hibbs does the countdown with our “Chinese” wireless launch controller and pushes the button. (sic sarcasm included)

Well there was a heck’va a chuff and the rocket popped off the pad and sailed up quite high, maybe 150 feet to 200 feet traveling in an easterly arc direction, flopping around in the air the entire time with the motor burning like a road flare. This thing hits the ground, flops a few times again (probably a nozzle problem!) and then has a “BIG” chuff again this time going in a westerly direction up in the air to maybe 200 to 300 feet. Thank heavens our HPR launches were sparsely attended!!!!

The rocket now comes back and hits the ground, flops around and then WHAM! The motor caught and the thing fortunately for us, roars off in a southern track well away from us and the few spectators we had at a 30 degree angle.

Uuuhhhmm, The flier had a tracker in the rocket and even though it had an “off nominal” flight that whacked the ground twice, he actually found the remains as the tracker and I don’t know the brand survived! Thing is, there were no fins left on the airframe! When the thing bashed itself on the ground twiice, it managed to snap off the fillet, gusseted fins each time it hit. I guess the remnants of the fillets were enough to stabilize when the rocket took off in the southerly direction.

How the thing took off finless to the south in a straight, low level, 30 degree or less trajectory is beyond me. Craziest
rocket launch I have ever seen in my wretched life.

I distinctly remember when the airframe took off to the south (like I said, I’m glad our launches were poorly attended)
I couldn’t see any fins on the rocket. When the flier recovered it, and yes he found this stupid low angled flight of a rocket, I witnessed the airframe and there were just bits of where the fins used to be. Must have been enough to keep is straight on its low angled, and eventually high velocity flight to the south.

Ahhhhh, I remember there was a kevlar harness used as anything else whould’a snapped in such a low level, high velocity deployment.

Kurt Savegnago
 

Jim Hinton

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Hi Folks;

One for the ages, I had to sit down and straighten out my memory of this. I corroborated it with my wife who was also a witness, at least to the best extent possible. This happened at Northern Colorado Rocketry's 2016 Mile Hi Mayhem launch. Two intrepid rocketeers were endeavoring to fly a 'N' class hybrid. This rocket was about 20' long and comparatively thin. I don't think any part of the airframe was over 6 inch diameter. The two fliers had been working on it for quite a while. I'm sure it was a task to get it on the pad and erected. The rocket was erect and word was passed that they were making final preparations. A hybrid that size will always attract a crowd and this was no exception. Everyone had stopped other activities to watch this launch. I am not an expert on hybrids, but this was the point where things started to go a little.....different. One of the two fliers stands abruptly and starts to run from the pad. He wasn't jogging, he was sprinting. The other flier did not seem to get the memo. He continued diligently working away at the base of the pad. For reasons still unknown, the entire rail and rocket shifted over to an angle about twenty degrees from vertical with an audible 'clank'. Within two seconds of that occurrence, an ejection charge fired in the forward airframe, and the nosecone ejected along with a relatively small piece of recovery gear, landing in the prairie about fifteen feet away from the rocket, no shock cord visible.
Good time to scrub a flight, you betcha! Absolutely no chance, of course. I look at the pad and the remaining rocketeer has assumed the Jesse Owens mode as well. Fire is visibly leaving the nozzle and... What followed can serve as a lesson in the importance of launching vertically with a nose cone attached. The hybrid ripped skyward to about a hundred feet and then performed three awesome loops, the pattern describing a corkscrew aimed at the ground. At the bottom of the third loop, the rocket found terra firma again and began an epic land shark sequence. At point there was so much smoke and dust in the air, it is impossible to note much detail. The rocket got airborne at least two more times, as high as 250 feet before returning for another encore of the dirt dance. Visibility has become non-existent. Rocketeers are responding to instinct and heading downrange to combat the inferno. Joe Hinton wisely announces over the PA for everyone to stay put until the rocket finishes. If it seems like this went on for a long time, that's only because it did. I recall the event being at least fifteen seconds long, my wife says at least thirty seconds. Two amazing outcomes, first and saddest, as near as I can tell no one filmed this. Secondly and most awesomely, no one was hurt and nothing but the rocket was damaged. About the time the motor finally stopped, I was expecting to see the prairie ablaze for 1/2 mile in all directions. Not even a burn mark, nothing at all. I very much doubt that I will ever witness another launch event to compare to that one. It would probably be for the best if I don't anyway.

Jim
 

BABAR

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Mine was a little ironic. I had the Evel Knievel Estes Sky cycle. The pad with the little 3 foot Rod. I can't remember the motor but the motor lit fine, the rocket popped up off the rod and promptly landed on the ground "upright" (driver up, simulated wheels down) and ran around in little circles looking for all the world like a regular little old land motorcycle.

Then popped the nose and the rolled up chute.

No fire, no particular specatacle, but it was somewhat amusing. If there was ever a true rocket configured to do a landshark routine, that was it.
 

Mike Haberer

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A few years back I had an Estes Shadow on a D12-3 get stuck on the launch rod (note: realized I needed to sandpaper them occasionally). The thrust vector was such that it aligned with one of the launch pad legs, causing the pad to tilt over. When the launch rod was horizontal the rocket took off. My son caught multiple pics on his iPhone in sequence. No one in that direction. Just missed the tree, which would have been spectacular. The rocket did not survive.

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Rocketjunkie

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CATO..CATO..CATO.....grain oxidize over?
Sparky propellant, too low Kn. Propellant burns, extinguishes, relights & repeat. Propellant works well at a higher Kn. I have a slow sparky propellant that I must run at a Kn of 400 to get a good burn.
 

jrap330

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Sparky propellant, too low Kn. Propellant burns, extinguishes, relights & repeat. Propellant works well at a higher Kn. I have a slow sparky propellant that I must run at a Kn of 400 to get a good burn.
So you believe engine was good....just too low average impulse for your size rocket?
 

OverTheTop

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I don't have anything too impressive to add, except a little C powered rocket that launched and did some skywriting. I was thinking "where is this going to be pointing when it goes stable?" CG shifted forward as the motor burns. The thing went stable and came at the flight line like an Exocet. It acutally hit a puddle that was two feet in front of a couple of spectators, about five feet from me. Scary quick.
 
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Rocketjunkie

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Too big a nozzle throat for a slow burning propellant. Motor was by Tom Henderson (Thunderflame).
 

caveduck

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Another all-time classic landshark - 1985, NARAM-27 in Houston, Internats flyoffs for E RCBG. Motor of choice at the time was still the FSI F7 (yeah it was officially an E motor for competition purposes). Bernie Biales had his pod detach from the glider at ignition. The pod flopped onto the ground, took careful aim, headed straight for the launch tent and proceeded to chase Chris Tavares around for the remainder of the 9-second burn. It almost seemed to be tracking him. Nobody was hurt and we laughed about it for years. It was called a "landshark" even then (the SNL skit was 1975), but I'm not sure if that was the first use of the term since F7's had a tendency to misbehave hilariously. That flight may or may not have also been the origin of the "9 seconds of terror" moniker for the F7.
 
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