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


Page 3 of 9 FirstFirst 1 2 3 4 5 6 7 ... LastLast
Results 61 to 90 of 270
  1. #61
    Join Date
    11th October 2016
    Location
    Twin Cities, MN
    Posts
    298
    Hope this helps.
    If you guys have any further questions about parachutes or rigging, please just let me know.
    I'd be happy to help in any way possible.

    Chris
    TRA 16662
    L1: 30 October 16, 3" Formula 75, 29mm H123, 871 Ft.
    L2: 13 May 17: 4" Tomach, 54mm K650, 6756 Ft.

  2. #62
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    mikec,

    Thanks for your reply. You are a steely eyed rocket man. Landing at 15 feet per-second is equivalent to simply dropping the piece from one meter. Impact should be about 7,000 pounds force assuming the 350 pound booster leaves a 2 inch dent in the soil. Estimating the dent, of course, is the thing.

    Were going to see if some friends in FEA can run a 1 meter drop test on the booster.

    Feckless Counsel


  3. #63
    Join Date
    18th January 2009
    Location
    Savannnah, Ga
    Posts
    7,709
    Happy New Year Feckless!

    You have a great project & I wish you success on this venture.
    Definitely a long hard road with many choices to make.

    Recovery is the beyatch.....hope for the best......prepare for the worst!
    I've snapped 4800lb line like it was kite string, when things went south on a 300lb project.

    Drogue stripped, and main opened to quite a shock load. Parts horizontal [payload, nc, fincan] rather than vertical stacked.
    But other than minor repair to one fin & replacing 1 zippered tube...it flew again! Prepare for the worst!!!
    Jim Hendricksen
    L-3 Tripoli 9693
    [ICBM, Orangeburg,SC R.I.P.] - QCRS ,Princeton ILL - MDRA , Price Maryland - Woosh, Bong Wisconsin- ROCC, Charlotte NC , ICBM Camden SC
    "Made" member of Chicago & Carolina Rocket Mafia
    Rocketry...........an exact science.......but not exactly !!!

  4. #64
    Join Date
    20th June 2010
    Posts
    22
    I had plans of doing a full scale.

    Wedge Oldham

  5. #65
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    TRF,

    Today was our first design review including core team, MDRA board members and Tripoli TAP members. Total attendance was 12 people. Review included a summary PowerPoint presentation, flythrough of the 3D model and simulation results from the FEA team. Criticism was well received. We have several pages of follow-up notes. We also received commitment for construction space beginning March 2017.

    Consensus is this project flies April 2018. That is the most reliable date for an MDRA / Higgs Farm flight. Given Higgs is the place of historic flights our first hope is to fly there.

    Feckless Counsel

  6. #66
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    TRF,

    Attached are some of the slides discussed at this week's design review. Included are:

    1. Basic details of our proposed construction.
    2. Sequence of flight to 5,200 feet.
    3. Booster separation schematic.
    4. Capsule and tower separation schematic.

    Feckless Counsel
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Semi-monocoque Details.PNG 
Views:	166 
Size:	194.8 KB 
ID:	310287   Click image for larger version. 

Name:	Redstone Flight Sequence Proposal A.PNG 
Views:	171 
Size:	83.2 KB 
ID:	310286   Click image for larger version. 

Name:	Booster separation scheme.PNG 
Views:	159 
Size:	189.9 KB 
ID:	310288   Click image for larger version. 

Name:	Capsule separation scheme.PNG 
Views:	155 
Size:	170.7 KB 
ID:	310285  

  7. #67
    Join Date
    27th January 2009
    Location
    Oregon
    Posts
    2,165
    How confident are you of the main body freefall q streamlining and having high speed or tumbling causing recovery issues.

  8. #68
    Join Date
    23rd November 2013
    Posts
    2,215
    I started to ask you to share the PowerPoint when you previously mentioned it. Please share more if you can. Very interesting.

  9. #69
    Join Date
    7th July 2013
    Location
    Toronto
    Posts
    3,303
    Quote Originally Posted by burkefj View Post
    How confident are you of the main body freefall q streamlining and having high speed or tumbling causing recovery issues.
    I was thinking the same thing. Well not in the same words but I was going in the same direction of being concerned with a drogue-less, free-fall and the mass of the objects. Of course not knowing the mass is at the root of the concern.
    Michael Pitfield
    TRA 14579 L2
    NAPAS BoD
    URRG
    MARS
    CRC

  10. #70
    Join Date
    9th May 2009
    Posts
    1,577
    Ditto. I think if you try to bring this stuff down drogueless you will strip the mains almost guaranteed. I've never seen a big project try to do dual deploy of any kind, most are challenged enough getting the chute out at apogee intact.

  11. #71
    Join Date
    27th January 2009
    Location
    Oregon
    Posts
    2,165
    Agreed, open things when they are going slow, track and recover...

  12. #72
    Join Date
    18th March 2012
    Location
    Huntsville, AL
    Posts
    9,083
    This project looks cool! I will definitely be following this.
    Matt, Tripoli #14257
    L1 11/13/16
    L2 2/25/17
    L3 Spring 2018....
    Facebook Youtube



  13. #73
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    Everyone,

    Thanks for your comments on recovery. A significant part of the design review considered recovery area, altitude and thrust-to-weight ratio. Dual deploy option was developed anticipating an ability to lift the project one mile altitude. Drogueless summersaulting, flat spin and nosediving trajectories were considered. The effect and hazards of including a drogue were also debated.

    Single apogee deploy and flight to 3,000 feet is a simplifying specification. And we all understand how simplicity favors success.

    Feckless Counsel

  14. #74
    Join Date
    1st April 2016
    Posts
    49
    Subscribed!
    Currently, I have launched a total of 13 rockets with a combined impulse of: 76.25 Newton Seconds

    Updated 11-1-17

  15. #75
    Join Date
    20th February 2009
    Location
    Cayuga, Indiana
    Posts
    12,886

    3/4 Mercury Redstone

    Quote Originally Posted by Feckless Counsel View Post
    I would propose a 3/4-scale Mercury Redstone for flight March / April of 2017.
    Fleckless, from your first post you provide a projected date as above. Will this be at LDRS36 in Maryland then?
    Last edited by dixontj93060; 28th January 2017 at 03:28 AM.
    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

  16. #76
    Join Date
    30th January 2016
    Location
    US > OK > NE
    Posts
    3,475
    Quote Originally Posted by dixontj93060 View Post
    Fleckless, from you first post you provide a projected date as above. Will this be at LDRS36 in Maryland then?
    Quote Originally Posted by Feckless Counsel View Post
    Consensus is this project flies April 2018. That is the most reliable date for an MDRA / Higgs Farm flight. Given Higgs is the place of historic flights our first hope is to fly there.
    Apr 2018

  17. #77
    Join Date
    20th February 2009
    Location
    Cayuga, Indiana
    Posts
    12,886
    Quote Originally Posted by dhbarr View Post
    Apr 2018
    Oh, I didn't catch the one year schedule slip.
    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

  18. #78
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    dixontj93060,

    We really want to fly this project at LDRS 36. Our host club never refused the project but it is clear they prefer to separate it from LDRS. Given the field, crowd size and other logistics that is completely understandable. Respectfully we have backed off and will begin construction about 10 March, a date otherwise more convenient to our construction facility. We expect 6 weeks total construction time.

    Availability in the fall is unreliable because Higgs and the surrounding properties are working farms. That puts the next available and reliable launch date early 2018.

    You could say we have a full year’s schedule slip. We like the idea this project was too large and dangerous for LDRS.

    Feckless Counsel

  19. #79
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    TRF,

    Just for fun. Below is the scale study from our design review.

    Feckless Counsel
    Attached Thumbnails Attached Thumbnails Click image for larger version. 

Name:	Scale Study.PNG 
Views:	281 
Size:	76.3 KB 
ID:	311220  

  20. #80
    Join Date
    20th February 2009
    Location
    Cayuga, Indiana
    Posts
    12,886
    Quote Originally Posted by Feckless Counsel View Post
    TRF,

    Just for fun. Below is the scale study from our design review.

    Feckless Counsel
    Given the flight profile of the full scale Aussie V2 and its lightweight construction techniques, and seeing this comparison, I am now getting very worried.
    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

  21. #81
    Join Date
    27th January 2009
    Location
    Oregon
    Posts
    2,165
    Diameter is smaller and they are saying they are using a Q motor, where the V-2 used an O-25,000.

    Quote Originally Posted by dixontj93060 View Post
    Given the flight profile of the full scale Aussie V2 and its lightweight construction techniques, and seeing this comparison, I am now getting very worried.
    Last edited by burkefj; 7th February 2017 at 05:08 PM.

  22. #82
    Join Date
    20th February 2009
    Location
    Cayuga, Indiana
    Posts
    12,886
    Quote Originally Posted by burkefj View Post
    Diameter is smaller and they are saying they are using a Q motor, where the V-2 used an O-25,000.
    Well yes, but the mass? V2 was very lightweight build. Just the tower on this thing has to be fairly hefty.
    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

  23. #83
    Join Date
    30th January 2016
    Location
    US > OK > NE
    Posts
    3,475
    ?? I show this anticipated at ~10% less mass?

  24. #84
    Join Date
    27th January 2009
    Location
    Oregon
    Posts
    2,165
    Quote Originally Posted by dhbarr View Post
    ?? I show this anticipated at ~10% less mass?
    I dont' think he believes the mass calculation based on the size, I think the structure looks pretty light, but we'll see how it works out, I'm sure they can do a good estimate of that.

  25. #85
    Join Date
    26th November 2009
    Posts
    4,907
    Quote Originally Posted by dixontj93060 View Post
    Given the flight profile of the full scale Aussie V2 and its lightweight construction techniques, and seeing this comparison, I am now getting very worried.
    It appears they are doing a construction analysis so they could be in good shape. The Q powered Pershing missile failure some years ago was a "builtup" rocket I heard they say it structurally failed at a transition though
    I didn't read a final analysis so that might be incorrect. The Aussie V2 at the outset was designed to be low and slow and the builders certainly were successful in that regard. People who were calling for "a larger" motor
    didn't recognize the capabilities of the V2 design but the rocket did exactly what the builders designed it to on the motor chosen. Any motor larger and it could have structurally failed.

    Kurt

  26. #86
    Join Date
    20th February 2009
    Location
    Cayuga, Indiana
    Posts
    12,886
    Quote Originally Posted by ksaves2 View Post
    It appears they are doing a construction analysis so they could be in good shape. The Q powered Pershing missile failure some years ago was a "builtup" rocket I heard they say it structurally failed at a transition though
    I didn't read a final analysis so that might be incorrect. The Aussie V2 at the outset was designed to be low and slow and the builders certainly were successful in that regard. People who were calling for "a larger" motor
    didn't recognize the capabilities of the V2 design but the rocket did exactly what the builders designed it to on the motor chosen. Any motor larger and it could have structurally failed.

    Kurt
    I may make a special trip to Higgs Farm just to watch this "baby."
    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

  27. #87
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    TRF,

    Please consider the following:

    1. Five-to-one ratio of thrust-to-weight is preferred especially where big EX meets big airframe.
    2. Lower risk EX motors are designed to neutral thrust curves operated at marginal pressures.
    3. Maximum Higgs Farm altitude for single deploy flight is 3,500 feet.

    If you generally concede these points then there is potential conflict between item 3 and the first two. That is to say you may be over 3500 feet given 5:1 for 6 seconds in 8 inch diameter by -inch wall 6061 aluminum design.

    For sake of argument let’s say we are presently at 800 pounds all in except the motor.

    Feckless Counsel

  28. #88
    Join Date
    21st July 2015
    Posts
    41
    suscribed.


  29. #89
    Join Date
    15th December 2011
    Location
    Too far from the event horizon.
    Posts
    1,752
    Perhaps reefing the chutes, released at break, and letting them fall under a pilot until the altitudes you mentioned? This would be dual-deploy... ish... and should minimize the chance of components rotating into a ballistic freefall position...


    Later!

    --Coop
    "For although the nepenthe has calmed me, I know always that I am an outsider; a stranger in this century and among those who are still men." --HP Lovecraft

    Custom crafted recovery: http://paramedichutes.com

  30. #90
    Join Date
    18th December 2010
    Location
    Maryland, 20794
    Posts
    485
    Coop,

    Thanks for your reply. We’ve discussed this a lot since December. Plan now is to keep it 3,300 feet (1 kilometer) altitude and spill the laundry on top. Decision is driven by the potential forces at mains deployment after free fall.

    To achieve that flight we are considering a dual thrust motor. There are several reasons to favor that profile. We want 5:1 thrust to weight at lift off. We want to throttle down for altitude target. We may also operate higher pressure early in the burn where case temperatures are lower.

    I visited the construction facility this afternoon. It’s looking really good. Open area is about 50 x 90 feet. Electricians are almost done. Place is freshly painted. Many machine tools have arrived awaiting installation. We should have access about 15 May.

    Feckless Counsel


Similar Threads

  1. Replies: 2
    Last Post: 13th June 2016, 05:05 AM
  2. [Wanted] Mercury Redstone
    By Brent in forum Yard Sale / Wanted
    Replies: 4
    Last Post: 30th June 2013, 10:46 PM
  3. Mercury Redstone
    By thobin in forum Scale
    Replies: 3
    Last Post: 21st July 2010, 05:12 AM
  4. MMX Mercury Redstone
    By cliveroonie in forum Low Power Rocketry (LPR)
    Replies: 16
    Last Post: 2nd October 2005, 11:46 PM
  5. Mercury Redstone help
    By matt_taylor in forum Low Power Rocketry (LPR)
    Replies: 34
    Last Post: 6th July 2003, 02:22 AM

Posting Permissions

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