Help Support RocketryForum by donating using the link above or becoming a Supporting Member.


Results 1 to 13 of 13
  1. #1
    Join Date
    20th August 2014
    Location
    Montreal
    Posts
    78

    Deployment problems on Giant Leap Rocketry's Vertical Assault

    *Disclaimer: not GLR's fault*

    This summer, I flew to try to get my L3 (Canadian L3). The going up part of the flight was good, but coming down, the main parachute got stuck in the body. Anyways, the rocket was undamaged but the failure to deploy lost me the L3. In the end, only my pride was hurt. Here's a video of the launch just for fun:

    https://www.facebook.com/neil.woodco...0966164736116/

    The main parachute had been a bit of a snug fit on the ground, but I was able to pull it out easily enough to make me confident it would work in flight. The main in this case is a 48 inch nylon parachute. Post flight, I noticed 2 things:

    1. The folded parachute had rolled on its side and had become jammed at the mouth of the body tube
    2. The kevlar parachute protector, which was already full of pyrodex residue from previous tests, felt sticky to the touch and had a pretty high friction coefficient with the FG body tube


    Based on these observations I have come up with some possible solutions. Of course, I'm looking for feedback from the experienced people on this very forum.

    1. Try a new folding technique. Preferrably one that folds the parachute into a longer, slimmer package. As well, the shockcord may need to be folded better, as it looks like it had a role in jamming the parachute in the tube
    2. Get a smaller parachute. If it landed fine with only a drogue, who says it needs a parachute as big as 48 inches?
    3. Clean the kevlar parachute protector between flights. I've already done this
    4. Maybe wrap the parachute and protector in a sabot of some kind. Cardstock might work.


    Any help is appreciated!

    Last edited by Neilw; 11th January 2017 at 05:47 PM.
    Chief Designer of the Aurelius - Won 2nd Place, 2016 IREC Basic Category
    Chief Designer of the Arcturus - Won 2nd Place, SDL Payload Challenge, 2015 IREC

    "Don't worry 'bout it!" - Space Concordia
    "A new rocket is pretty, but a flown rocket has character!" - Handeman

  2. #2
    Join Date
    5th December 2013
    Location
    MD
    Posts
    6,388
    Things I would do:
    1. Z-fold your harness
    2. More BP
    3. Smaller chute (with that premade fin can, you can take a harder landing, like you said)
    4. Don't be afraid to wash your chute protector and harness (but don't do it with another load of laundry or the clothes might turn gray)


    John S. ---- NAR #96911 ---- TRA #15253 ---- MDRA #067 ---- BARC #028
    L1, 3/15/14: Aerotech Sumo, CTI H133BS
    L2, 6/21/14: Giant Leap Vertical Assault, CTI J240RL
    L3, 3/12/16: MAC Performance Radial Flyer, CTI M1101WH
    Altitude: 13,028', L3 flight; Speed: Mach ???, L3 flight

  3. #3
    Join Date
    27th May 2015
    Location
    Charleston, SC
    Posts
    128
    1+ Bat-mites suggestions. Also ground test, ground test after performing steps 1 to 3 above.
    Good Luck!!

    Fred,
    L2, ROSCO member
    KG4YGP

  4. #4
    Join Date
    20th August 2014
    Location
    Montreal
    Posts
    78
    Quote Originally Posted by Bat-mite View Post
    Things I would do:
    1. Z-fold your harness
    2. More BP
    3. Smaller chute (with that premade fin can, you can take a harder landing, like you said)
    4. Don't be afraid to wash your chute protector and harness (but don't do it with another load of laundry or the clothes might turn gray)
    I did a z-fold, but that may have been part of the problem. It was still jammed up in the body with the tape intact. Maybe I should try a weaker tape? I was using white masking tape but maybe I should have gone with green.

    Quote Originally Posted by FMarvinS View Post
    1+ Bat-mites suggestions. Also ground test, ground test after performing steps 1 to 3 above.
    Good Luck!!
    I'll try to get some testing time. It gets a bit hard to test for me, though, since I live in the city.
    Chief Designer of the Aurelius - Won 2nd Place, 2016 IREC Basic Category
    Chief Designer of the Arcturus - Won 2nd Place, SDL Payload Challenge, 2015 IREC

    "Don't worry 'bout it!" - Space Concordia
    "A new rocket is pretty, but a flown rocket has character!" - Handeman

  5. #5
    Join Date
    5th December 2013
    Location
    MD
    Posts
    6,388
    Regarding ground testing, if you don't do it, then you take what you get at the field. If your rocket crashes, you could be out significant $$$. If it works on the ground, it will work in the air.

    John S. ---- NAR #96911 ---- TRA #15253 ---- MDRA #067 ---- BARC #028
    L1, 3/15/14: Aerotech Sumo, CTI H133BS
    L2, 6/21/14: Giant Leap Vertical Assault, CTI J240RL
    L3, 3/12/16: MAC Performance Radial Flyer, CTI M1101WH
    Altitude: 13,028', L3 flight; Speed: Mach ???, L3 flight

  6. #6
    Join Date
    2nd September 2010
    Posts
    2,458
    I keep a bottle of baby powder in my chute box. Makes stuff slide a lot better. Put a gob in the chute when you pack it for better visibility when it pops opens.

  7. #7
    Join Date
    23rd March 2013
    Location
    Akron, OH
    Posts
    367
    Quote Originally Posted by Neilw View Post
    Maybe I should try a weaker tape? I was using white masking tape but maybe I should have gone with green.
    I was having the same problem, and one of the guys at our field suggested putting a few starter cuts in the tape with an x-acto knife. Have not had any problems since.

    YMMV
    Bill
    Member - MTMA
    Akron, Ohio

    "Rather than cursing the rose bush for having thorns, it is better to thank the thorn bush for having roses."

    Currently searching for that sweet spot between "Paralysis by Analysis" and "Extinct by using Instinct"

  8. #8
    Join Date
    11th January 2013
    Location
    Old Bridge,,,,,,,,,,,,, New Jersey
    Posts
    4,921
    Quote Originally Posted by Bat-mite View Post
    Things I would do:
    1. Z-fold your harness
    2. More BP
    3. Smaller chute (with that premade fin can, you can take a harder landing, like you said)
    4. Don't be afraid to wash your chute protector and harness (but don't do it with another load of laundry or the clothes might turn gray)
    Please don't ask me how I know this,, lol..

    Teddy

    ( and don't mention it if my wife is with me )




    www.Onebadhawk.com

    Ted Chernok
    Old Bridge New Jersey
    METRA- BoD- New York..
    URRG- Way upstate New York..
    MDRA- Maryland..
    QCRS- Illinois- Best politicians money can buy ( Tim L. )..
    Kloudbusters- Kansas..
    NAR # 87063
    Tripoli # 14443
    Level 3

  9. #9
    Join Date
    11th January 2013
    Location
    Old Bridge,,,,,,,,,,,,, New Jersey
    Posts
    4,921
    I had a tight fit in my 54 mm minimum D "Altitude Seeker"...

    1-- Clean the BP residue from the inside of the airframe..
    2-- Lot's of baby powder all over everything..
    3-- It's super important that when you use a masking tape restraint on a Z folded harness
    that the tape be put on the end of the Z folds where both tails come into the fold package..

    Teddy




    www.Onebadhawk.com

    Ted Chernok
    Old Bridge New Jersey
    METRA- BoD- New York..
    URRG- Way upstate New York..
    MDRA- Maryland..
    QCRS- Illinois- Best politicians money can buy ( Tim L. )..
    Kloudbusters- Kansas..
    NAR # 87063
    Tripoli # 14443
    Level 3

  10. #10
    Join Date
    6th September 2009
    Posts
    1,490
    Harness is taped together and not opening? Umm, don't tape the harness?

  11. #11
    Join Date
    19th January 2009
    Location
    Stafford VA
    Posts
    6,851
    Quote Originally Posted by Buckeye View Post
    Harness is taped together and not opening? Umm, don't tape the harness?
    +1 on this. I know it sounds like it was kind of tongue in cheek, but it really is the best suggestions. If you are z-folding your harness and taping, and it doesn't open, then you don't have enough force on your ejection to warrant needing the z-folds. Don't try to correct one perceived problem by creating another and using a larger charge. Just don't do the unneeded taping.
    Handeman

    TRA #09903 L3 :D 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. #12
    Join Date
    20th February 2009
    Location
    Cayuga, Indiana
    Posts
    12,604
    Before selling, I had flown my VA many times without a failure. The main compartment is fairly long. On the flight...

    What brand 48" chute?

    How much BP?
    L3, TRA #11847
    Tripoli Indiana #132
    Tripoli Central Illinois #59
    Central Illinois Aerospace (NAR) #527
    Chicago Rocket Mafia, "Big Bucks" Dixon
    ___________________________________

    Quiet little voices creep into my head. -- We Were Promised Jetpacks

  13. #13
    Join Date
    23rd March 2013
    Location
    Akron, OH
    Posts
    367
    Quote Originally Posted by Buckeye View Post
    Harness is taped together and not opening? Umm, don't tape the harness?
    Agreed, but sometimes my OCD just wants to keep everything neat and organized.

    Sorry, I must get back to washing my pencils now.

    Bill
    Member - MTMA
    Akron, Ohio

    "Rather than cursing the rose bush for having thorns, it is better to thank the thorn bush for having roses."

    Currently searching for that sweet spot between "Paralysis by Analysis" and "Extinct by using Instinct"

Similar Threads

  1. Giant Leap Vertical Assault build thread.
    By Bat-mite in forum High Power Rocketry (HPR)
    Replies: 62
    Last Post: 15th September 2014, 08:31 PM
  2. [SOLD!] Giant Leap Vertical Assault 3.0 - immaculate and ready to launch
    By dbarrym in forum Yard Sale / Wanted
    Replies: 52
    Last Post: 3rd July 2012, 09:24 AM
  3. Giant Leap 3" Vertical Assault Motor Estimates
    By jerryb in forum High Power Rocketry (HPR)
    Replies: 8
    Last Post: 28th November 2007, 07:05 PM
  4. Giant Leap Vertical Assault Review
    By Phil125 in forum Product and Vendor Reviews
    Replies: 16
    Last Post: 3rd May 2006, 07:11 PM
  5. Giant Leap - Vertical Assault 3.0
    By FLRocketry in forum High Power Rocketry (HPR)
    Replies: 9
    Last Post: 9th April 2006, 03:40 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •