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  1. #31
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    Quote Originally Posted by manixFan View Post
    To be honest, I think you are obsessing over the orientation a bit much. In the end I don't think it really matters as once out in the airstream the pilot chute/nosecone are going to pull everything out straight.
    That's not necessarily true in a free-bag configuration. What if ONLY the pilot makes it into the airstream?


  2. #32
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    Quote Originally Posted by jahall4 View Post
    That's not necessarily true in a free-bag configuration. What if ONLY the pilot makes it into the airstream?
    It still should pull everything out straight. D-bag are more reliable than than the fold and wrap that we do in most rocket flights aka the "nomex burrito". A skydivers chute is a type of deployment bag and those are extremely reliable. The Airforce uses D-bags again very reliable. Keeping everything orderly on a deployment is a key to successful chute deployment, z-folding shock cords and d-bags both are methods of organizing the gear and keeping it organized during the flight.

    Rich

    NAR# 99154

    L3-4x upscale Estes Cherokee-D- AT M1297W 5/28/2016 http://www.rocketryforum.com/showthr...r-rharshberger

    TriCities Rocketeers NAR section# 736 http://www.tricitiesrocketeers.org/

  3. #33
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    Quote Originally Posted by rharshberger View Post
    It still should pull everything out straight.
    Well sure, but I'm considering beyond what "should" happen into what could happen even if it's very unlikely. Mechanically it does appear possible that the free-bag method could leave the chute in the airframe.

  4. #34
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    Quote Originally Posted by jahall4 View Post
    Interesting, makes sense. Variation of just attaching the chute to the harness down some from the cone. In you config down is all the way into the tube.
    That variation would keep the cone near the chute (I try to avoid that) and it is also likely that the inertia of the cone would pull out the chute early (trying to avoid that too). The objective is to get the chute/pilot to rise above everything before the chute opens. It only takes a few seconds for that to happen, but it's pretty cool "live".

    Jim

  5. #35
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    Quote Originally Posted by JimJarvis50 View Post
    That variation would keep the cone near the chute (I try to avoid that)...
    I'm not sure how you come to that conclusion as even I haven't decided how far "down some" is :-)

    Quote Originally Posted by JimJarvis50 View Post
    ... and it is also likely that the inertia of the cone would pull out the chute early (trying to avoid that too).
    That's unavoidable regardless since the chute itself acts as spring to get itself out of the bag, any tension at all (even no tension) is going to free that bag once the shroud lines are out.

    Quote Originally Posted by JimJarvis50 View Post
    ...The objective is to get the chute/pilot to rise above everything before the chute opens.
    Then it seems to me more harness is your friend, but you see lots of configs where the nose is attached directly to the shroud lines.

  6. #36
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    Quote Originally Posted by jahall4 View Post
    I'm not sure how you come to that conclusion as even I haven't decided how far "down some" is :-)

    That's unavoidable regardless since the chute itself acts as spring to get itself out of the bag, any tension at all (even no tension) is going to free that bag once the shroud lines are out.

    Then it seems to me more harness is your friend, but you see lots of configs where the nose is attached directly to the shroud lines.
    The point is to get the cone away from the chute. Fouling due to the cone is why many deployments fail. It doesn't matter to me how far down some is. I don't want the cone on the same harness.

    Not sure what unavoidable and spring mean? With the bag configured per the pics I posted, the bag won't open until tension is pulled between the pilot and the upper air frame. At that point, the chute is above everything else.

    You want enough harness so that the chute will be above everything when it opens. A harness about the same length as what is between the upper air frame and the fin can is sufficient.

    Jim

  7. #37
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    Quote Originally Posted by jahall4 View Post
    That's not necessarily true in a free-bag configuration. What if ONLY the pilot makes it into the airstream?
    Then you've clearly done something wrong and haven't done enough testing. If you pull the d-bag off and the chute stays in the airframe, that's a clear indication you don't understand how to rig a deployment bag, or probably a regular chute as well.

    Quote Originally Posted by jahall4 View Post
    I'm not sure how you come to that conclusion as even I haven't decided how far "down some" is :-)
    ...
    That's unavoidable regardless since the chute itself acts as spring to get itself out of the bag, any tension at all (even no tension) is going to free that bag once the shroud lines are out.
    ...
    Then it seems to me more harness is your friend, but you see lots of configs where the nose is attached directly to the shroud lines.
    You've asked for advice from folks who have used deployment bags. Yet you seem unsatisfied with all the information that has been provided from flyers who have successfully used deployment bags on a variety of flights. You make it clear you don't have any experience and as far as I can tell you haven't tried to rig anything up yet to see how it works for yourself. If you did any testing on your own I don't think you'd make the statement about the chute acting like a spring.

    At this point it seems to me the best course of action is to get your chute and deployment bag and start doing your own testing.

    Good luck,


    Tony
    why do people put so much stuff in their sigs?

  8. #38
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    Quote Originally Posted by manixFan View Post
    Then you've clearly done something wrong and haven't done enough testing. If you pull the d-bag off and the chute stays in the airframe, that's a clear indication you don't understand how to rig a deployment bag, or probably a regular chute as well.



    You've asked for advice from folks who have used deployment bags. Yet you seem unsatisfied with all the information that has been provided from flyers who have successfully used deployment bags on a variety of flights. You make it clear you don't have any experience and as far as I can tell you haven't tried to rig anything up yet to see how it works for yourself. If you did any testing on your own I don't think you'd make the statement about the chute acting like a spring.

    At this point it seems to me the best course of action is to get your chute and deployment bag and start doing your own testing.

    Good luck,


    Tony
    You are clearly one of these guys who expects everything to go perfect in your flights. Even though it is highly unlikely, a pilot only deployment is possible because it is a separate component. Surely you've done this enough to know that a few anecdotal successes are not conclusive proof of "best way". As far as the "spring" comment you can argue about that with Gene: https://www.youtube.com/watch?v=_0YH...=youtu.be&t=81

  9. #39
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    Quote Originally Posted by jahall4 View Post
    You are clearly one of these guys who expects everything to go perfect in your flights. Even though it is highly unlikely, a pilot only deployment is possible because it is a separate component. Surely you've done this enough to know that a few anecdotal successes are not conclusive proof of "best way". As far as the "spring" comment you can argue about that with Gene: https://www.youtube.com/watch?v=_0YH...=youtu.be&t=81
    I understand where you are coming from, but I tend to agree with Tony.

    The way I set up my d-bag, a pilot only deployment is all I want. More is better, but pilot only is all that should be needed for a clean deployment just like drogue only is all you need for apogee deployment. If you don't get the pilot out, they you have problems.

    As for the chute springing out of the bag, I don't think any chute should be able to come out of the bag with
    (even no tension) is going to free that bag
    . The whole point of the d-bag is to hold the chute until the shrouds stretch out and things align before the chute is pulled out and opens. If your chute can fall out of your bag without pulling it out, I think you have the wrong size bag. Any pull on the bag should pull bag out of the payload long before the chute gets pulled out of the bag. If you can pull the bag off the chute and leave the chute in the payload, you don't have the right set up. That should never happen.
    Handeman

    TRA #09903 L3 3/29/2015

    "If you don't use your head, you have to use your feet!" my Dad

    Tripoli Central Virginia #25 - BattlePark.org

  10. #40
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    Quote Originally Posted by Handeman View Post
    The way I set up my d-bag, a pilot only deployment is all I want. More is better, but pilot only is all that should be needed for a clean deployment just like drogue only is all you need for apogee deployment. If you don't get the pilot out, they you have problems.
    Exactly!

    Quote Originally Posted by Handeman View Post
    As for the chute springing out of the bag, I don't think any chute should be able to come out of the bag with.
    Your reading more into my comment than there is. As you know when using the elastic bands to keep the shroud lines there is no way the chute can just fall out. Once again go watch Gene's video (https://www.youtube.com/watch?v=_0YH...=youtu.be&t=81) and take that up with him.

  11. #41
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    Quote Originally Posted by jahall4 View Post
    Exactly!



    Your reading more into my comment than there is. As you know when using the elastic bands to keep the shroud lines there is no way the chute can just fall out. Once again go watch Gene's video (https://www.youtube.com/watch?v=_0YH...=youtu.be&t=81) and take that up with him.
    Exactly what? All you need is a pilot chute out, or if it doesn't come out you have problems?

    Your link to Gene's video doesn't work. I just get video not available. What exactly is he saying? The chute should fall out of the bag?
    Handeman

    TRA #09903 L3 3/29/2015

    "If you don't use your head, you have to use your feet!" my Dad

    Tripoli Central Virginia #25 - BattlePark.org

  12. #42
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    Quote Originally Posted by jahall4 View Post
    Exactly!

    As you know when using the elastic bands to keep the shroud lines there is no way the chute can just fall out.
    The parachute can definitely leave the bag with the shroud lines still in the elastic! I recently went through a bunch of scenarios trying to prevent that from happening.

    Granted, my setup is non-standard. I’m holding the chute in the bag and the bag closed all inside a nose cone shoulder with an ARRD. And the pilot is my drogue.
    Scott Wathey
    TRAPHX VP and Waiver Getter
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  13. #43
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    Quote Originally Posted by watheyak View Post
    The parachute can definitely leave the bag with the shroud lines still in the elastic! I recently went through a bunch of scenarios trying to prevent that from happening.

    Granted, my setup is non-standard. I’m holding the chute in the bag and the bag closed all inside a nose cone shoulder with an ARRD. And the pilot is my drogue.
    Did the chute deploy? Are you sure the chute came out before the shrouds left the elastic?
    I don't have a lot of experience with d-bags, but I don't think I would use that one if the chute could come out that easily.
    Handeman

    TRA #09903 L3 3/29/2015

    "If you don't use your head, you have to use your feet!" my Dad

    Tripoli Central Virginia #25 - BattlePark.org

  14. #44
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    Quote Originally Posted by Handeman View Post
    Did the chute deploy? Are you sure the chute came out before the shrouds left the elastic?
    I don't have a lot of experience with d-bags, but I don't think I would use that one if the chute could come out that easily.
    These were all hypothetical scenarios as I was tweaking the layout. In my first couple iterations it was possible to shake the parachute free from under the flap while trying to simulate the motion while under drogue. The rocket flies at the end of this month. I’ll post a pic later tonight as it’s totally unorthodox. It’s a Fruity bag and Iris Ultra.
    Scott Wathey
    TRAPHX VP and Waiver Getter
    TRA 7726
    KF7EIV

  15. #45
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    Quote Originally Posted by Handeman View Post
    Exactly what? All you need is a pilot chute out, or if it doesn't come out you have problems?
    Yes that exactly what you are saying "All you need is a pilot chute out"

    Quote Originally Posted by Handeman View Post
    Your link to Gene's video doesn't work. I just get video not available. What exactly is he saying? The chute should fall out of the bag?
    Worling for me: https://www.youtube.com/watch?v=_0YH...=youtu.be&t=81

  16. #46
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    Quote Originally Posted by watheyak View Post
    These were all hypothetical scenarios as I was tweaking the layout. In my first couple iterations it was possible to shake the parachute free from under the flap while trying to simulate the motion while under drogue. The rocket flies at the end of this month. I’ll post a pic later tonight as it’s totally unorthodox. It’s a Fruity bag and Iris Ultra.
    The flap was closed? What was holding it while under drouge? Are the Fruity bag intended for device like that?

  17. #47
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    Quote Originally Posted by jahall4 View Post
    The flap was closed? What was holding it while under drouge? Are the Fruity bag intended for device like that?
    Yes the flap was closed. A Kevlar strap is holding it in place in the nose one shoulder. The drogue/pilot is also attached to this strap. When the ARRD releases the strap, the drogue is allowed to pull the chute out of the bag.

    The Fruity Chutes bag intended for the device? Odd question. Neither yes or no.

    My goal for the recovery in this project was to have dual deployment out of a single airframe break, using a deployment bag and keeping it all in one piece. I also wanted the events to be sequentially linear to prevent some of the issues Jim Jarvis and others have mentioned.
    Last edited by watheyak; 16th January 2018 at 06:06 AM.
    Scott Wathey
    TRAPHX VP and Waiver Getter
    TRA 7726
    KF7EIV

  18. #48
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    I read both deployment bag threads.
    I use them a lot, even used a rigid system using tubes for a very long small diameter deployment.
    I have never put this much thought into it.

    M
    Last edited by MClark; 16th January 2018 at 02:52 AM.

  19. #49
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    Quote Originally Posted by MClark View Post
    I read both deployment bag threads.
    I use them a lot, even used a rigid system using tubes for a very long small diameter deployment.
    I have never put this much thought into it.

    M
    Amen, d-bags are really simple, much simpler than they appear.
    Rich

    NAR# 99154

    L3-4x upscale Estes Cherokee-D- AT M1297W 5/28/2016 http://www.rocketryforum.com/showthr...r-rharshberger

    TriCities Rocketeers NAR section# 736 http://www.tricitiesrocketeers.org/

  20. #50
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    Quote Originally Posted by MClark View Post
    I read both deployment bag threads.
    I use them a lot, even used a rigid system using tubes for a very long small diameter deployment.
    I have never put this much thought into it.

    M
    While I don't disagree that deployment bags are easy once you understand them, it is sometimes hard for people to wrap their head around ideas. Personally I learn best from hands on as well as detailed pictures and examples.
    Michael Pitfield
    TRA 14579 L2
    NAPAS BoD
    URRG
    MARS
    CRC

  21. #51
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    <snipped for brevity>
    Quote Originally Posted by jahall4 View Post
    That's unavoidable regardless since the chute itself acts as spring to get itself out of the bag, any tension at all (even no tension) is going to free that bag once the shroud lines are out.
    I watched the video you linked and you have mischaracterized what he says in the video. He shows as heís packing it how easy it is to shake the chute out of the bag and does says the chute is like a spring. But you can also clearly see that once the chute is in the bag, even with all the shroud lines out, it does not Ďspringí out of the bag. Even when he shakes the bag it does not spring out, only a small portion of it falls out. The video does not support your claim that ďany tension at all (even no tension) is going to free that bagĒ. As I said earlier, if you were to actually try any of this yourself you would not make some of these statements.

    And Fruity Chutes Iris chutes are very different than typical chutes so what applies to them does not necessarily apply to other chutes. Iíve used the Iris model and it definitely packs differently than other chutes.

    Iíll move along now but my advice still stands: get your own chute and deployment bag and practice rigging the chute to understand how it works. Youíre arguing with a bunch of folks who have successfully used deployment bags yet from what I understand you have yet to even handle one.


    Tony
    why do people put so much stuff in their sigs?

  22. #52
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    Quote Originally Posted by manixFan View Post
    <snipped for brevity>I watched the video you linked and you have mischaracterized what he says in the video. He shows as he’s packing it how easy it is to shake the chute out of the bag and does says the chute is like a spring. But you can also clearly see that once the chute is in the bag, even with all the shroud lines out, it does not ‘spring’ out of the bag. Even when he shakes the bag it does not spring out, only a small portion of it falls out. The video does not support your claim that “any tension at all (even no tension) is going to free that bag”. As I said earlier, if you were to actually try any of this yourself you would not make some of these statements.

    And Fruity Chutes Iris chutes are very different than typical chutes so what applies to them does not necessarily apply to other chutes. I’ve used the Iris model and it definitely packs differently than other chutes.

    I’ll move along now but my advice still stands: get your own chute and deployment bag and practice rigging the chute to understand how it works. You’re arguing with a bunch of folks who have successfully used deployment bags yet from what I understand you have yet to even handle one.


    Tony
    So he uses the word "spring" but he does it mean "spring"? Whatever man and yes it works exactly as he and I have characterized. YOU are characterizing it differently to defend a misstatement. Obviously tension in this case refers the tension created by pilot. The weight of the chute when coupled with the compression of the chute is enough to a least get some (or all) of the chute out of the bag. I'll post a video of what you say is impossible later.

  23. #53
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    Quote Originally Posted by mpitfield View Post
    While I don't disagree that deployment bags are easy once you understand them, it is sometimes hard for people to wrap their head around ideas. Personally I learn best from hands on as well as detailed pictures and examples.
    I concur as well. Much easier because packing it is very delbert/methodical/repeatable. It's unfortunate I have waited this long to give them a try. I'm actually more confident in deployment of a large chute with the bag than without, and I have yet flown one.


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