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full scale Hellfire at 5 pounds?

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MWC

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Frank -

This is fantastic build and the result is amazing! Missile Works started as a "Missile Kit" manufacturer (along with parts and electronics), so I've always had a soft spot for "ordnance". Looking forward to your flight results and hoping you'd kit these for sales (or barter).
 

TopRamen

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Thanks for sharing all the Pics' of how you made the Structure.
That's a pretty radical and impressive Technique.
Just you wait til' I get my Hands on some of that Depron!!!
Lightweight Fiberglass Cloth meets Depron Foam???
I'm already fantasizing about getting into Rocket Boosted Gliders! Depron will surely be the end of me!

Awesome Job on the Rocket. You really went at it 110% and made it happen, which is better than most Build Threads.
I recently had to slow my Progress on my 29mm Crossfire, but I went to the Thread and updated it to let Folks know that I had shelved it for a bit, and why. A lot of Build Threads here just fizzle out, and Ideas similar to yours don't teach anyone anything.
I've learned a lot here in this Thread, and it is opening all sorts of new Avenues in the way my Mind works when I'm thinking of what I can build.
Your Technique really opens up a lot of Options.:D

Hope to see more unique Build Threads like this.:pop:
 

burkefj

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Thanks for the nice comments. You know, I'm also curious how much weight a light fiberglassing would add.
I don't think you need it for stiffness, more just for handling and impact damage.......

Frank
 

burkefj

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Forgot to post this, this was a test run I was doing for a partially constructed tube section doing some loading tests.
Here it is with 75# of lead on it. This is only a portion of the circumference of a 7" diameter body section with only four stringers and not fully sheeted. Rated compressive strength for 6mm depron is greater than 21 psi with 10% deformation, I think I have about 19 based on the structure tested with no deformation. With a full section I think it could take 150 pounds or more. I did not test it to destruction, as I wanted to use this for some finishing/vinyl application tests.

Frank

WP_20141216_001.jpg


WP_20141216_002.jpg
 
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burkefj

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I got a chance to fly the hellfire at Fire in the Sky(FITS) In washington this morning. I was a bit hesitant since there is some scrub brush, but I decided to go for it. I used a 29mm H-135 motor that was the largest I could fly with the designed nose weight. 80 oz rtf with 48" chute. Perfect flight. It weather cocked slightly into the wind, but did not bobble, my altus Metrum Easy Mini blew the ejection charge and it came down nice and soft with just a bit of surface rash. It held up to the 5 g load, flight loads, ejection and recovery as I had hoped, my altimeter bay worked fine. The rail button mounting worked great too. I was worried about max speed as well on the 2mm foam skin but it handled the 171 fps(117 mph) just fine. Given all the things I could have had problems with it was as good as I could have hoped for. Flew to just under 650 feet. This was really a proof of concept to try to build something that normally would be around 23 pounds ready to fly using normal hp construction and get it to fly on small motors. People will say put a bigger motor, but its diminishing returns, for every pound in the rear I 'd have to add 2 pounds to the front and quickly exceed the structural load capability, and not have enough room for a larger chute, etc. I'm pretty happy, it's a nice low and slow rocket a a great size(7" by 60") or so.

Here is the video my son took.

[video=youtube;-Q0MrnZ-Bys]https://www.youtube.com/watch?v=-Q0MrnZ-Bys&feature=youtu.be[/video]

Frank

IMAG0008.jpg
 

les

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WOW

Great build techniques
Great paint job
Great flight
 

jsargevt

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That was a great flight! A beautiful build with some great techniques! Honestly, being able to fly such a large rocket on a small motor is a great thing! Not all rockets need to go a mile high or break the sound barrier to be cool.
 

CzTeacherMan

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Very cool build and flight. Been watching this thread since the start, glad to see it come to fruition
 

Zeroignite

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I really enjoyed watching this launch live at FITS. That's a stunningly light build for such a large airframe :)
 

burkefj

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I flew this twice again today. First flight on the same H-135 motor, nice straight boost off of a 12' rail to 750'. Then I decided to stress test the airframe with an I-205. Perfect straight boost, just a bit of roll. Perfect recovery with just a bit of fin crunch on one tip that I bent back into shape. It has some road rash in places but for a foam rocket to survive an I-205 to 1250 feet, i was pretty happy about that. I don't notice any roll on an H-135 but the I it was there, I think a few of the forward fins are slightly angled but again, no indication of any instability. I added three large quick links to the nose to put my CG at the right spot.

Frank
 

burkefj

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Here's the flight video:

[video=youtube;ZXxyGCmOmOc]https://www.youtube.com/watch?v=ZXxyGCmOmOc"]https://www.youtube.com/watch?v=ZXxyGCmOmOc[/video]
 

burkefj

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Here's a photo prepping for launch at Tri-Cities

9372897_orig.jpg
 

burkefj

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Here was another great flight at tri-cities yesterday on an I-200W

[video=youtube_share;VddyJtaCh3M]http://youtu.be/VddyJtaCh3M[/video]
 

burkefj

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I took her out of retirement, repainted her and will fly again this weekend fingers crossed on an I-205
 

BABAR

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Nice rocket and perfect flights.

I got a kick out of the background chatter.

Talking about"make sure you miss the power lines."

I could just see you calling the power company.

"Can you please get my rocket down from the power line?"

"What kind of Rocket is it?"

"It's a 5-foot full-scale Hellfire missile."

"...........click..dial tone...... "
 

teepot

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That's great. I use clear plastic ornament shells for the front of my missiles. Put a simulated seeker under that. I've also used styrofoam balls to make a rocket.
Where do you get the foam you use. I've seen your youtube posts and have wanted to try your technique to build a rocket. And what is the stuff called.
 

burkefj

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The foam is called depron, it's much lighter than the paper covered foam board, and much better quality and more consistent thickness, I use 6mm for the centering rings and stringers, and 3mm for the skin. It's available from rcdepron.com

Frank

That's great. I use clear plastic ornament shells for the front of my missiles. Put a simulated seeker under that. I've also used styrofoam balls to make a rocket.
Where do you get the foam you use. I've seen your youtube posts and have wanted to try your technique to build a rocket. And what is the stuff called.
That's great. I use clear plastic ornament shells for the front of my missiles. Put a simulated seeker under that. I've also used styrofoam balls to make a rocket.
Where do you get the foam you use. I've seen your youtube posts and have wanted to try your technique to build a rocket. And what is the stuff called.
 

Bill S

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So what kind of altitude did the rocket achieve? At the end, when I saw the rocket coming down in front of the trees, for a split second I thought "oh not a tree!". :)
 

burkefj

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Just under 1200 feet, it's a perfect motor, you see the whole flight, recovery is close, no additional nose weight needed.

So what kind of altitude did the rocket achieve? At the end, when I saw the rocket coming down in front of the trees, for a split second I thought "oh not a tree!". :)
 
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