Demystifying Deployment Bags

Discussion in 'Recovery' started by mpitfield, Jan 14, 2018.

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  1. Jan 31, 2020 #31

    jahall4

    jahall4

    jahall4

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    Not real sure what your thinking is based on you drawing since the deployment bag is not shown, but I can share 3 axioms that may help. 1) The bags purpose is to ensure, as much as possible, the chute, its shroud lines, and itself come out of the airframe as a unit undestributed as possible. 2) The pilot's (not to be confused with drouge) only purpose is to pull the bag of the chute. 3) The loop in the top of the main's only purpose (other than for hanging in my closet ;)) is to keep the bag and the pilot attached. Purists would use the "free-bag" method, so no loop would be needed, but of course that means an extra component to track during the recovery.

    Here is a video the includes some footage of retrieval you may find helpful. Don't be confused by the "Redundant Main":

    Note: it is also possible not to use a pilot at all, attaching the top of the bag "up" the harness, but some may argue that is more prone to failure.

    When you get it rigged post a picture or two, be easy then to note potential problems.

    Good Luck!

    Allen Hall (NAR #98014, Tripoli #16881)
    Vice President & NAR Advisor
    Music City Missile Club (NAR Section #589, Tripoli Prefecture #134)
     
    Last edited: Jan 31, 2020
  2. Jan 31, 2020 #32

    tollyman

    tollyman

    tollyman

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    After thinking about it more, I'm not sure there is any other way to make use of the deployment bag in it's intended manner without using the free bag method and recovering the nosecone seperatly. I was hoping to avoid recovering seperate components, especially because my tracker is in my nosecone.

    Just so I'm clear this is how the free bag recovery scheme would work. The nosecone would attach to deployment bag and the pilot chute. When deployed the pilot would pull the deployment bag out of the rocket and when the shock cord is at full length and pulls tight the parachute shroud lines would pull loose of the elastic and then the parachute would fall out of the deployment and hopefully deploy.

    One issue I see with that is that the parachute for the pilot would have to be sized correctly so that it would not be falling faster than the main chute and having a chance to fall into the main and potentially getting tangled/collapsing.

    Although I am not a fan of recovering two seperate items, it seems like the most clean way to deploy the deployment bag without having sewn top loop
     
  3. Jan 31, 2020 #33

    jahall4

    jahall4

    jahall4

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    The pilot need only be attached to the bag to ensure it is pulled off.
     
  4. Feb 1, 2020 #34

    Ez2cDave

    Ez2cDave

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