paging L3 jack from BALLS

Discussion in 'United Kingdom Rocketry' started by watermelonman, Sep 27, 2015.

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  1. Sep 27, 2015 #1

    watermelonman

    watermelonman

    watermelonman

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    Is the fellow named Jack, who I met at BALLS and successfully certified L3 on an M1101 around?

    I was bummed to leave the playa before your group launch main event, and am hoping to hear all about it as well as catch some data and footage.
     
  2. Sep 29, 2015 #2

    MClark

    MClark

    MClark

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    I think he is Brewster.
    I have his email on my other computer, but I just got home 2 hours ago

    Mark
     
  3. Oct 1, 2015 #3

    jb803

    jb803

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    Hi,

    I just got back to the UK and am slowly recovering from the jetlag.

    It launched and then after flying beautifully straight for 4 seconds something terrible happened to a fin at about Mach 2.3 (assuming it flew according to the simulation). It didn't really survive the resulting corkscrew (though thankfully the rental casing did!).

    The fins had a aluminium honeycomb structure with carbon fiber panels to provide the required stiffness to prevent failure due to flutter. From the looks of it the adhesive that we used to attach the panels has itself sheared - we're wondering whether a panel came off mid-air and then the subsequent drop in stiffness of the fin caused it to bend under the aero loads.There were a series of strain gauges on the fins which logged the loads observed at the root during flight. We've not had a chance to look at the data but it might be able to tell us if the fin failure was a result due to the CF breaking off and then the aluminium bending or whether there was significant flutter before even the CF panel failed.

    In terms of data and videos - we have some videos of the launch but they only arrived in the UK today ( due to ticket prices we all took different flights back). The SD cards of the onboard cameras are MIA. From the flight computer we've got baro, accelerometer, gyro and strain gauge logs which we're yet to analyse but will do so in the next few days. I can't remember the rate at which it logged them but I think it's fast enough and with a sufficient accuracy on the accelerometer that we should be able to reconstruct the flight path through numerical integration.

    There are lots of still pictures around but again they only got back to the UK today so we've not had a look or the chance to upload many. The remnants of the lower half can be seen here: https://twitter.com/cuspaceflight/status/648362603593396224 .The aluminium fin assembly is now a large paperweight on my desk :p

    Jack
     
  4. Oct 1, 2015 #4

    watermelonman

    watermelonman

    watermelonman

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    Awesome! Thanks for sharing and I will keep an eye on that URL for more pictures and data.
     

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