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  1. #1
    Join Date
    18th January 2009
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    Chute Release - Another Application

    So I was mulling over several discussions where someone had a high altitude flight and experienced difficulty when an inadvertent apogee deployment took place. Then the idea struck me. Add a Chute Release to the main and if you get an unplanned apogee deployment, you have a fail safe that might save you. Heck, I don't see why this would not pass a L3 certification as you are taking an extra step to ensure you recover on the field. Set the Chute Release to 100' below your lowest mains event and you are covered.

    Discuss...

    Al Gloer - TRA/NAR L3 (President Emeritus - CATO)
    2017 - The Year of the Bike Redux - 2,234 miles to go

  2. #2
    Join Date
    25th October 2016
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    Use two CRs linked together so only one has to work for the mains to be released.


  3. #3
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    22nd August 2015
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    I really like this idea. I've had a chute release activate while stuck in a body tube before when the laundry wasn't completely ejected. Essentially, that would occur if everything went to plan by your proposed method. This sounds like a great way to insure that popping the main at apogee doesn't result in a lost rocket.
    NAR #100940, RIMRA & CMASS
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  4. #4
    Join Date
    5th December 2013
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    Wouldn't work too well with a D-bag. Has possibilities, though.
    John S. ---- NAR #96911 ---- TRA #15253 ---- MDRA #067 ---- BARC #028
    L1, 3/15/14: Aerotech Sumo, CTI H133BS
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  5. #5
    Join Date
    15th October 2015
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    Quote Originally Posted by Incongruent View Post
    Use two CRs linked together so only one has to work for the mains to be released.
    This is a well known technique. I remember K'Tesh mentioned this way back when Chute Release was in pre-production.


    As far as using a CR(or two ) as a back-up in case there is early or reversed ejection, I think that would be a prudent choice if you really needed to make sure.

    I can't see why it would be a problem for certification. Backups have to be in place anyway for L3 correct? Only downside would be making a cato $130 more expensive.
    NASA success rate since 2000: 94.7%
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  6. #6
    Join Date
    15th October 2016
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    Huntsville AL
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    Quote Originally Posted by Cabernut View Post
    This is a well known technique. I remember K'Tesh mentioned this way back when Chute Release was in pre-production.

    As far as using a CR(or two ) as a back-up in case there is early or reversed ejection, I think that would be a prudent choice if you really needed to make sure.

    I can't see why it would be a problem for certification. Backups have to be in place anyway for L3 correct? Only downside would be making a cato $130 more expensive.
    Some believe that this lead to an increased tangle opportunity. My thoughts along that line are to tie a loop in the cord just away from the chute attach point and use longer tethers so they're more likely to fall away if one fails (Mine never failed while I had it, but It does happen occasionally).
    "I'm at least 70% confident about whatever I say (90% of the time)"- college me

    NAR 101195
    Level 1: Big SAM, 9/10/16

  7. #7
    Join Date
    23rd November 2013
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    Speaking of K'Tesh...........he has not been around lately.

  8. #8
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    20th April 2012
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    Quote Originally Posted by Cabernut View Post
    . . . Only downside would be making a cato $130 more expensive.
    JLCR would probably survive a CATO unharmed. Last year I had a Mega Der Red Max come down ballistic (CTI VMax ejection charge failure) and had to dig out the JLCR that was buried about 6" in the ground. Cleaned it off and it worked fine.
    NAR Level 2 #96210

  9. #9
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    Quote Originally Posted by Nytrunner View Post
    Some believe that this lead to an increased tangle opportunity. My thoughts along that line are to tie a loop in the cord just away from the chute attach point and use longer tethers so they're more likely to fall away if one fails (Mine never failed while I had it, but It does happen occasionally).
    Like a loop of kevlar cord longer than the shroud lines that will replace the supplied tether? So upon release it will fly back away and not tangle?

    It's a great product, I can't wait to try it out.
    NASA success rate since 2000: 94.7%
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    My personal success rate: 90.5% <--- new goal to hit 95%
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  10. #10
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    13th April 2011
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    Same here. After digging my Jart out from ballistic return due to a failed motor ejection, the CR came thru without a scratch. Tough they are.

    Ben

  11. #11
    Join Date
    15th July 2015
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    Quote Originally Posted by Cabernut View Post
    Like a loop of kevlar cord longer than the shroud lines that will replace the supplied tether? So upon release it will fly back away and not tangle?
    Yes, just like that. I do it this way when I want the shrouds to unroll but the canopy to stay closed to get a 'streamer' effect. Once the JLCR releases, the inflation of the canopy is pretty rapid and the 'pop' will fling the JLCR clear and prevent tangles. I've used it this way several times. I keep several different lengths of Kevlar loops in my box for each chute that I want to use it that way.

    ATCS(AW) Tom Keith, USN, ret. _____NAR 99781 L1_____MDRA 212
    SEVRA, NAR 621http://www.sevra.org/ Tripoli East North Carolina (Bayboro), TRA #65, http://ncrockets.org/, MDRA http://www.mdrocketry.org/
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