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Life, Death and possible resurection of an Interceptor E

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stantonjtroy

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Hi all.
Well, my son and I attended the NARHAMS sport launch today. Great event. Hats off to all who cordinated and worked the event. We decided that my Interceptor E with the insane boxart paintjob had been a hanger queen long enough. I had in my posession a F24-4t reloadable that I thought would do great as I built it just on the heavy side of ideal. My mistake was attaching the ejection charge per MFG instructions. I hear the collective sucking wince out there. I know better but it's been years since I flew a reload and simply forgot. Weak I know but that's my story and bla bla bla. Anyway... great boost, like a homesick angle. Clean arc over, and...and...AND!!! :eek:Lawndart from the pit. I expected to do a dustbuster recovery but was very pleased with what I found, realatively speaking. Fins popped off clean at glue joints, no splintering thanks to a light (1/4 oz) glass laminate. motor/stuffer tube intact as were the pods and spikes. The only things that need replacement are the forward BT and the Nose cone; and decal sheets. I'll be calling Estes tomorrow to order replacements. I'll probably just do an all white finish this time.......or not. We'll see. I have before and after shots I'll post tomorrow. For anyone interested I do recomend this motor; Just pour the ejection powder directly in the charge well in the fwd closure and cap it with tape to keep the black powder grains in constant contact with the delay grain. Not doing so was my mistake. As I said, I do know better.

Good flying,
Troy
 

Handeman

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Not sure why you say attaching the ejection charge as per MFG instructions is a mistake. Just make sure you don't skip step 18. With the motor held in a NOZZLE DOWN position, gently shake the motor several times to settle the ejection charge into the delay cavity above the delay element.

I've been doing it that way for years and have never had a failure due to the powder not firing. Now if you got some assembly grease on the delay grain, well....
 

stantonjtroy

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With the motor held in a NOZZLE DOWN position, gently shake the motor several times to settle the ejection charge into the delay cavity above the delay element.QUOTE]

Did that. Was carefull about grease on the delay grain as well. Like I said, I'm not new to it. I think it had to do with the fact that I had to assemble, prep and load the rocket a significant time before I could get to the pad (had to be ready when a window opened as there were other activities going on adjacent to the launch site) that setting it down a few times and handeling it at the prep site, RSO table and milling around before I could get to the pad would cause what little compaction there was to loosen. That's why I useally just fill the well and tape it off. Most of the guys I flew HP with adopted this method for the same reason. In any event, the flight up was spectacular and the new parts have allready been ordered. She'll be flying again in no time.
 

Handeman

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On a 24/40 Hobbyline motor, I'm not sure just filling the little well and taping it off would provide enough powder to get reliable ejection. The HP casings have much larger wells designed to hold the whole charge, the Hobbyline isn't.

I know with the 29/40-120 casing, when I fly it in my 4" Thug, I top off the red cap with FFFFg and then put it on. The extra powder has to go into the well in order for the cap to fit on the motor. I do that because the amount of powder that comes with the reload isn't enough. It has always popped the nosecone, but the charge was weak enough that on a few occations the chute never came out of the BT.

Was the red cap still on the motor when you got it back?
 

rstaff3

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It was great chatting with you Troy. Sorry again about the lawn dart. That rocket was a work of art.
 

rokitflite

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You could have AT LEAST sent it with your wife to the hobby store so I could see it before you killed it!:(
 

GregGleason

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No doubt, that was a work of art.

I'm glad you are going to rebuild. That's character, a good trait to pass on.

Greg
 

dpower

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Thats a shame - she was a nice looking I-E. While I've never had a 24/40 ejection fail (though I have had lawn darts due to poor delay choice), I wonder if I'm on borrowed time? I suppose this is one of those things that folks have widely varying experiences with, but is there a "common wisdom" variation on following the instructions? I was planning on using a 24/40 load the next time I launch my I-E, now I'm going to be all nervous about it! ;)
 

stantonjtroy

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Thats a shame - she was a nice looking I-E. While I've never had a 24/40 ejection fail (though I have had lawn darts due to poor delay choice), I wonder if I'm on borrowed time? I suppose this is one of those things that folks have widely varying experiences with, but is there a "common wisdom" variation on following the instructions? I was planning on using a 24/40 load the next time I launch my I-E, now I'm going to be all nervous about it! ;)
I wouldn't be too worried about it. I've used the same loads in the same case a number of times since with no problems. I'm just going to toss it up to a bad choise in preping and handeling the motor and rocket long before launch.
 

kelltym88

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Just about the same thing happened to me. I've got parts, just waiting for a spot to repair it in my schedule...
 

MattieShoes

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Judging from the other folk at launches I've been to, ejection charges from the motor are quite reliable... I've seen them go early and I've seen them go off too soon or too late, but they've almost always deployed at some point. The altimeter based systems seem much more likely to fail, though that could be repeated human error...
 

RimfireJim

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Thats a shame - she was a nice looking I-E. While I've never had a 24/40 ejection fail (though I have had lawn darts due to poor delay choice), I wonder if I'm on borrowed time? I suppose this is one of those things that folks have widely varying experiences with, but is there a "common wisdom" variation on following the instructions? I was planning on using a 24/40 load the next time I launch my I-E, now I'm going to be all nervous about it! ;)
I was taught by PunkRocketScience to put a small bit of dog barf wadding on top of the ejection charge before installing the red cap, the idea being that it will keep the powder in contact with the delay element even if the rocket arcs over. Don't cram it in there; use just enough to take up the empty space.
 

Mikus

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Here they are. Before, pending and After.
Oh no. I'm sorry. After putting all those decals on too. :y:

Well it looked nice. :eek:

I'm about to start an I.E. myself, not looking forward to the decals. :jaw:
 
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