Goin' for my L1

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kelltym88

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Well, it is finished. Here is a picture of the rocket I will be using Saturday for my L1 attempt. The PML Matrix. I just hope it doesn't rain. I'm planning on using a Pro 38 2 grain, and if all goes well I'll see if she can go up again on a 3 grain.
 

Rocketmaniac

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Good Luck on your L1!!!! The H153 is the same motor I got my L1 with......

Take pics!!!!
 

lalligood

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Excellent rocket-motor combo for a L1 attempt. Should stay nice 'n' low (~1500ft) which is exactly what you want to do for a cert flight. It'll make for a super flight on the 3-grain Pro38 too! Good luck & don't forget to take pics!!!!
 

Stymye

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good luck with the flight
I also certed on the h153
 

Bowhunter

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Go Kelly ...........Just do it............level 1 with a pml kit no probs
 

PunkRocketScience

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Good Luck! The Cessaroni motors are ALWAYS a good idea for cert flights...Less parts to mess up with. PML just updated their motor matix to include the CTI motors (so their newsletter says), so you might want to check that out to get your delay!
 

kelltym88

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Well, today was not a good day. There must have been something in the air that it was just not meant for me to cert L1. I'm still not sure what or why it happened , but it did. First off here's me next to my Matrix, Pro 38 H153 loaded and on the pad ready for take-off.
 

kelltym88

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Of course I was as nervous as all get out. Well ignition was no problem, took off beautifully. But about 200' up or so I heard this loud "pop" and I thought to myself, UH OH. Well the rocket continued straight up, hit apogee, turned over and came ballistic right into terra firma. It was not pretty. Here is the aftermath.
 

kelltym88

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There are a couple of theories I have: 1) Maybe the motor retention was not as good as it should have been. The washers I used just barely caught the edge of the motor. 2) The motor was given to me by an onsight vendor(which was kinda cool as I didn't have to pay for it). Well I'd never used a Pro 38 so he showed me how to load it. But he didn't tighten the motor all the way. I questioned this, but he said don't worry. Well, the resulting flight was the motor shot out the back and the result was disastrous.


But that was just the beginning of my day. More to come.
 

Donaldsrockets

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Ouch!!!

Sorry to learn about your mishap, I think I have seen this same type of failure happen myself wit the same devistating results.

From your pic, it appears that the booster section is repairable but it looks like the payload section is a total loss.:(

Better luck next time.:)
 

strudleman

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I had a similar problem with my son's PML Bull Puppy this weekend at RocStock XX, and this seems to be an issue with all PML (and other piston based) Rockets. Buildup of pressure above the engine and below the piston, if not relieved by a vent hole, will kick an engine out despite many motor rention systems. Additionally (or in the event that your motor retention is bullet proof), the piston will be forced up the BT, causing premature separate and most likely massive zipper damage. In the future, I'll be putting a vent hole below the piston of any PML kit I get.
 

gerbs4me

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ouch
better luck next time
It took me three trys to get my L1
 

HeadHunter

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Man that's a bummer...at least you core sampled with style, quite the photo.:(
I have several PML kits and at my first HP launch, one of the club members stopped me from launching without the vent hole below the piston. I had forgot about it until strudleman mentioned it. I guess the diameter of the body tube and rate of acceleration really come into play here.

As a side note, with apologies to vendors, always verify correct assembly and length of delay before launching if you don't know ask a club member most are very willing to help
 

kelltym88

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Originally posted by strudleman
I had a similar problem with my son's PML Bull Puppy this weekend at RocStock XX, and this seems to be an issue with all PML (and other piston based) Rockets. Buildup of pressure above the engine and below the piston, if not relieved by a vent hole, will kick an engine out despite many motor rention systems. Additionally (or in the event that your motor retention is bullet proof), the piston will be forced up the BT, causing premature separate and most likely massive zipper damage. In the future, I'll be putting a vent hole below the piston of any PML kit I get.

I too was at Rocstoc XX. Mine core sampled in the morning.
 

eugenefl

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Dude, that totally sucked! I was out there and saw your bird lift off, poop, and arc over into the ground. At the time I had no idea it was your rocket. :( Bummer man. Well, go rebuild your broken birds and try again. You'll get it.
 

kelltym88

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As I mentioned earlier, my Matrix core sample was just the beginning. There was a lot going on that day. I was really bummed after that first attempt, but I had alot of rockets with me. My friend Dave was there launching his own rockets for the first time ever. It was his first time building and flying. All of his flights went w/o a hitch. He had a Quest Icarus and an Estes Polaris(newer version). I was so proud, almost had tears......just kidding about the tears.


Anyway, I decided I woould fly my upscale Disruptor again. I made sure I loaded the motor correctly this time. I was a little nervous, but it was a beautiful flight and sucessful recovery.

Here's a couple of pictures...
 

kelltym88

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Sorry, not very good pictures. Had to stand so far away. Here's another right at lift-off...
 

kelltym88

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And another as it gets going up. Probably the best flight I had that day, except for my original Duece which was the first rocket I sent up that day.
 

kelltym88

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Another good flight was my Der Red Max Deuce. Flew great, NC seperated from the body, but all was recovered and no damage. This was part of one of those multiple launches, so I didn't get a launch shot of it. Here it is on the launch pad. This is slighlty upscaled (from a BT 60 to a BT 204) version, with 24mm MMT.
 

kelltym88

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Well, like I said there was alot of activity that day. I got to meet Eugene and Jason from the TdD. Eugene and I posed with our upscale 29mm Deuces. (See the TdD thread). Then there was a group picture. Then the wedding. Yes there was a wedding that day as well. Sometime during all of this, I was talking with my friend Jim and he mentioned that it was possible to cert L1 on a 29mm reload. So me and Dave proceeded to the What's Up Hobbies tent to inquire. Sure enough, he had an AT H248 (I think, or something close to it). But we didn't have the right casing. So Dave offered to buy them. He reasoned he would need them for his L1 attempt. How could I argue with that kind of resoning. So he purchased 2 Dr. Rocket 29mm casings the 240 and 360. Dave was determined to help me get my L1. Thanx Dave for all your support.



Oh, I also helped out a guy named Terry. He was terrified. He was so scared he was shaking. He was also attempting his L1 and asked me for my help in helping him build his motor. I was more than happy to oblige.

It turns out that as I was attempting to cert L1 again, Terry had his rocket on the same row as mine. Well now the anticipation is building up again. So was the nervousness. I started second-guessing myself. Did I load the motor right? Was the rocket built good enough for a stronger motor? And so on. Finally it was my turn. I was thinking to my self " Just get off the pad, just get the 'chute and you'll be fine"

3,2,1, ignition!!!!.....
 

kelltym88

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Get a good look, cause that's the last time you'll see my Disruptor as originally built. Actually the lift-off, flight and ejection all happened w/o a hitch. It was the landing that caused the problem. When it hit the ground the lower BT apperently was so stressed that the force caused the tube to unwind if you will. Like taking it along the seam line and unraveling it. BUMMER. My baby was busted and no L1. I was bummed.



One side note though, I did see Terry later, and his L1 cert flight was sucessful with the motor I helped him load. Way to go Terry, Congrats!!!
 

kelltym88

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So what was I to do. Give up? I thought about it. But I remebered that I had my 29mm Deuce all prepped and ready to go. What else could wrong, right?


Here it is on the launch pad.....
 

kelltym88

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Wrong!! Although Eugene got a great shot of it in the air (it looks like only one motor is lit, but both are. You see both smoke trails), he took it just seconds before all 4 fins were literally ripped off the rocket. The crowd really enjoyed it , and the LCO even mentioned "That's what we call a crowd pleaser." Well I wasn't pleased. In fact Fox 11 News may have captured it on video. Needless to say I wasn't to thrilled at this point with how my day had gone. But I was determined not to leave w/o a sucessful flight. What would I choose? My 125% Blue Bird Zero with an F-21? My Interceptor G? I chose to go with my Tres. After all TdD was there and I had to get that up in the air. It was getting late, so I just barely got it up to the table for check in. Hooked it up and waited. It was going to be part of one of those Multi- launches again.

5,4,3,2,1, ignition.....

It went up about 40-50 feet and took a sharp right turn. It was parallel to the ground and heading right out towards the HPR launch rods. Upon further examination, only 2 of the 3 motors lit. That was it. No more. I was done. It was a tough day, but I still had fun(?). I know I learned alot and I'll be back. Hopefully at the next ROCStoc I'll cert L1&2 that same weekend. Hope you enjoyed my little adventure.
 

kelltym88

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One more thing to add. About the Fox 11 News. I just watched the story they had and twice they showed my upcsale Disruptor taking off. Well that just made things a little bit better. In fact that was really cool. I'm so proud:D :D :D
 

kelltym88

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Forgot to add the picture of the 29mm Deuce in the air. Here it is...
 

SpartaChris

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Originally posted by HeadHunter
Man that's a bummer...at least you core sampled with style, quite the photo.:(
I have several PML kits and at my first HP launch, one of the club members stopped me from launching without the vent hole below the piston. I had forgot about it until strudleman mentioned it. I guess the diameter of the body tube and rate of acceleration really come into play here.
I saw your flight. My GF and I helped you find the motor for it. I remember the core sample you got. That wasn't pretty. If it helps, my friend's Thor Cato'ed that same day.. At least your's made it off the pad!

I flew my GF's Pteradactyl Jr. on a 2 grain Blue Thunder load on Friday and had the piston eject right off the pad. I had an upper vent hole, so I was at a loss. Took it to Andy Woerner who said I needed a vent hole below the piston as well because the pressure buildup right off the pad can be more than enough to kick the piston early (as I experienced first hand.) I put in the vent hole below the piston and what do you know, a perfect flight! Flew the same rocket on an I-300T as well, which had some serious kick to it. No problems at all.

Perhaps this is a size related issue. The Pteradactyl has a 4" body tube with a lot of open area. I consider myself lucky that I was able to get away without a vent hole below the piston in my PML Bull Pup while flying it on I-285R's. But that has a 3" body tube, so I don't know if the pressure buildup below the piston is managed better by the smaller tube diameter or not. But as Strudleman said, I will make sure to fly all of my PML or piston based ejection kits with a lower vent hole below the piston as well as an upper. I added one to my Bull Pup after the Pteradactyl issue and it flew perfectly fine with no issues.

-Chris
 
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