The Sledgehammer

11 responses to “The Sledgehammer”

1. 

   jitze

   Dec 7, 2008 at 9:05 am

   The configuration of the flight surfaces (tail fins) has me thinking there is more to the Sledgehammer than meets the eye. First of all the fact that one set of two fins is forward of the other set. Second the actual shape of the fins is intriguing. Appears to be basically a triangle with the furthest outboard apex snipped off, but the angle of the snip is different on the forard set versus the aft set, also the trailing edge of the triangles is different between the two sets.

   Virtual simulation? Real wind-tunnel? Adapted from previous succesful design? Poetic muse? I understand these things can come to bits if you don’t do it right – or even come adrift.

   I am agog to learn of the results

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2. 

   NYCArthur

   Dec 7, 2008 at 6:57 pm

   No way !

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3. 

   Leino88

   Dec 7, 2008 at 11:06 pm

   enough room for a cat in the payload??

   (kidding…. for the animal lovers out there):P

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4. 

   jurvetson

   Dec 29, 2009 at 10:20 pm

   heh, the NAR has an animal code. No vertebrates. I think this is a parsimonious way of saying you can’t launch anything that might be your sister’s pet.

   Have wondered about lobster.

   Here are a couple more shots I got of the beautiful launch…

   

   and punching through the clouds
   

   jitze – seems like a bunch of earlier comments are missing from this page. Did I answer this before?…. and where did Vanita’s cloning picture go?

   

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5. 

   jitze

   Dec 30, 2009 at 9:40 am

   I don’t recall you answering my question, but then my memory isn’t what it used to be…but then neither do I recall seeing Vanita’s clone picture which I am sure I would have remembered as being a veritable tour de force of cloning skill. I pride myself on my cloning skills and my ability to detect fellow perps, so I would have noticed. The change in attitude of the zipper pull and the knee-scuffs had me going for a while – and then I spotted the shadows. (Forget the memory fade problem, now I question my eyesight.)

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6. 

   jurvetson

   Dec 30, 2009 at 3:10 pm

   Alas, it was my memory lapse it seems. Thanks.

   It’s loosely based on the X-15, but it’s a scale up of a custom build by Giant Leap Rocketry.

   I built a pre-release prototype and tried to offer feedback, such as a stronger way to couple the motor thrust to the body (extra ring and coupler segment added between the metal motor ring and the bottom of the fins:

   

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7. 

   mebooyou

   Dec 30, 2009 at 11:57 pm

   That’s ridiculous!!!!!

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8. 

   Wind Watcher

   May 17, 2010 at 4:07 am

   Wow, big rocket. How high can you get with this rocket?

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9. 

   jurvetson

   May 17, 2010 at 3:58 pm

   about 1.5 miles. I can’t wait to download the computer flight files from Saturday where I launched it with its biggest motor yet, a M1850.

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10. 

    msyoung2012

    Sep 24, 2011 at 12:39 am

    This is absolutely awesome. Do you have any documentation of the design process? (Calculations, schematics, etc)

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11. 

    jurvetson

    Sep 24, 2011 at 12:55 am

    sort of

    

    Reply