If   you   want   to   build   an   advanced   water   rocket,   and   you   don’t   want   to   start   all   over   again   after   the   first   flight,   we   suggest building   a   recovery   system   for   your   rocket,   which   brings   the   rocket   safely   back   to   earth.   Let’s   begin   with   the   basics:   A parachute   deployment   mechanism,   the   most   common   recovery   system   for   a   water   rocket,   ejects   the   parachute   at   the right   time.   That   sounds   pretty   easy   but   in   fact   it   is   one   of   the   most   sophisticated   tasks   when   building   a   water   rocket.   The system has to be small, light and reliable.
THE TOMMY TIMER
There   are   numerous   approaches   for   parachute   deployment   mechanisms.   In this   tutorial,   we   show   you   how   to   build   a   mechanical   system    based   on   a Tommy    Timer .    Tommy    Timers    can    be    found    in    wind-up    toys    which    are available   in   toy   stores   and   on   the   internet.   After   removing   the   case   you   can   cut off   all   protruding   parts   of   the   timer   using   pliers.   You   should   also   remove   the plastic   handle   from   the   main   axel   by   repeatedly   clamping   it   in   a   vice.   After   that, bend   the   axel   using   two   sets   of   pliers.   The   modified   timer   will   later   be   the centerpiece   of   the   system.   You   may   wonder   why   we   use   these   mechanical timers    and    don’t    work    with    electronic    systems.    Well,    the    answer    is    pretty simple:     Mechanical     systems     are     way     easier     to     build      and     repair,     are significantly   lighter    and   a   lot   more   affordable    when   compared   to   electronic ones   –   this   is   especially   important   when   a   rocket   crashes   and   you   have   to   build a   new   parachute   deployment   mechanism.   But   luckily,   this   shouldn’t   be   the case   all   too   often   since   the   two   systems   we   want   to   show   you   in   this   video have already proven their reliability  with numerous flights.
WHICH SYSTEM IS SUITABLE?
The   first   system   we   want   to   show   you   is   called   Phoenix   6.   It’s   the   latest   version of    our    Phoenix    Parachute    Side    Deployment    System    and    is    optimized    for rockets   with   a   single   large   pressure   vessel.   For   rockets   consisting   of   multiple pressure     vessel     segments     we     recommend     building     a     Phoenix     Radial Deployment   System.   This   system   was   originally   developed   by   our   colleagues from   U.S.   Water   Rockets ,   but   we   adjusted   and   optimized   it   for   the   use   with   a lightweight mechanical timer.
PHOENIX 6
For   the   construction   of   the   Phoenix   6   Side   Deployment   Mechanism   you   will need   two   bottles .   It   is   necessary   to   use   the   same   bottle   type   you   have   already used   for   your   pressure   vessel.   Cut   off   the   bottom   of   one   of   the   bottles   using scissors   and   remove   the   thread   of   the   bottle   with   a   saw.   Now   you   have   to   cut   a big   opening    in   the   cylindrical   section   of   the   bottle.   In   this   case,   the   opening   is about   10   cm   /   3.9”   wide   and   there   should   be   about   3cm   /   1.2”   left   to   the   lower edge.   When   you   use   bottles   with   a   bigger   or   smaller   diameter,   you   have   to adjust   the   width   of   the   opening.   The   bottle   with   the   opening   will   later   be   the case   of   the   parachute   system .   But   of   course,   your   case   will   need   a   nosecone. You   can   either   glue   a   half   table   tennis   ball    on   top   with   epoxy   or   you   can   use the   nosecone   of   a   fireworks   rocket    for   that.   Now   take   the   second   bottle   and remove   both   the   bottom   and   the   neck.   The   remaining   cylindrical   section   will   be separated    in    two    equally    large    pieces.    One    of    these    pieces    will    be    the parachute door . If   you   want   to   paint   your   parachute   system,   you   can   do   this   now.   First,   sand and   clean   both   the   case   and   the   door.   We   recommend   using   plastic   primer before   applying   the   paint.   The   spray   paint   can   be   applied   as   soon   as   the   primer is dry. It‘s maybe necessary to spray several coats. After   that,   you   can   cut   out   two   round   base   plates   out   of   a   thin   plastic   plate. You   should   be   able   to   put   the   plates   into   the   system,   but   they   shouldn’t   be   too small   and   should   remain   in   place   without   any   glue.   After   you   have   placed   the plates   directly   at   the   lower   and   upper   edge   of   the   opening,   you   can   glue   them in    place    using    a    hot    glue    gun.    Please    be    careful    and    don’t    use    too    much adhesive. Now   it’s   time   to   mount   the   Tommy   Timer   you   have   modified   at   the   beginning. All   you   need   are   three   small   holes   in   the   case   located   slightly   above   the   lower base   plate.   Put   the   bent   axel   of   the   timer   through   the   hole   in   the   middle   and use   a   small   cable   tie   to   fasten   it.   The   parachute   door,   which   is   placed   over   the opening,   can   be   fastened   by   using   a   rubber   band.   Just   mount   a   loop   slightly under   the   upper   base   plate   on   the   case.   Now   you   can   wrap   the   rubber   band multiple   times   around   the   system .   Just   hook   the   rubber   band   over   the   bent timer axel. To   eject   the   parachute,   you   need   a   spring .   For   that,   you   can   use   a   part   of   a   thin walled   plastic   bottle.   You   can   attach   the   bottle   piece   with   wire   on   the   case   but you   can   also   take   the   whole   cylindrical   section   and   glue   it   in   place   with   a   hot glue   gun.   However,   if   you   use   this   method   you   have   to   watch   out   that   the parachute   will   pushed   out   of   the   opening   and   not   to   the   side.   The   parachute door can now be attached with a rubber band on the parachute.  
PHOENIX RDS
But   before   we   finish   the   construction   of   the   Phoenix   6   mechanism,   we   want   to take   a   look   at   the   Phoenix   RDS.   The   good   news   is,   that   it   consists   of   even   less components   than   the   Phoenix   6.   The   most   important   component   is   a   thin   but flexible   plastic   cover .      You   can   use   a   document   cover   or   a   thin   walled   bottle section   for   that.   Mount   the   modified   Tommy   Timer   at   one   edge   of   the   cover using   two   little   cable   ties.   On   the   opposite   edge   you   can   attach   a   rubber   band loop.   For   the   next   steps,   you   will   need   a   rocket   with   multiple   pressure   vessel segments.   Wrap   the   cover   around   the   connection   between   two   segments , then   wrap   the   rubber   band   around   it   and   hook   it   on   the   timer   axel.   Another rubber   band   attached   to   the   cover   and   the   nosecone   of   the   rocket   will   ensure that   the   cover   will   be   pulled   away    when   the   parachute   gets   ejected.   The Phoenix   RDS   is   now   already   on   the   same   level   as   the   Phoenix   6   System,   whose construction   we   described   earlier   in   this   video.   The   following   steps   are   identical with both systems.
LAST STEPS
To   prevent   the   rubber   band   sliding   over   the   bend   of   the   timer   axel,   glue   a   small   cable   tie   head    with   epoxy   or   superglue directly   at   the   bend.   Now   you   can   hook   in   the   rubber   band   once   again   and   wind   up   the   timer.   A   few   seconds   later,   the rubber   band   will   be   released   and   the   parachute   ejected.   Please   be   very   careful   when   testing   the   system   because   you   do not   want   to   get   the   rubber   band   flick   into   your   eyes.   Now,   the   only   thing   you   need   to   complete   the   construction   is   a   small trigger    which   holds   the   timer   in   place   until   the   rocket   launches.   Luckily   the   construction   is   fairly   simple.   You   just   need   a big   cable   tie!   Cut   the   long   part   off   so   that   the   remaining   cable   tie   is   only   5cm   /   2”   long.   Now   wind   up   the   timer   and   place the   trigger   underneath   the   small   cable   tie   you   used   to   attach   the   timer   so   that   the   timer   can’t   start   running.   Connect   the trigger   with   wire   and   a   rope   to   your   launch   pad   and   you   are   ready.   But   don’t   forget   to   attach   the   parachute   and   the system to your rocket first.
Spitze 3cm / 1.2 10cm / 3.9
Wind-up toy
Modified Tommy Timer
Painted system with nosecone
Base plates
System with spring and parachute
Rubber band wrapped around the system
1) System with trigger (before launch)
2) Timer is running (launch)
3) System opens
4) Parachute is ejected
ADVANCED COMPONENT TUTORIALS RECOVERY SYSTEMS
More tutorials Advanced component tutorials PDF PDF
To   succeed   with   the   construction   of   a   water   rocket,   you   will   have   to   work   very   precisely   and   carefully.   Especially   some   of   the   adhesives   are   pretty   dangerous. Thus,   please   wear   gloves   when   working   with   adhesive   or   epoxy   and   don‘t   breathe   in   the   gases.   It   is   recommended   to   work   outside   whenever   toxic   gases could   develop.   The   launch   of   a   water   rocket   may   needs   permission   from   the   competent   authority,   depending   on   your   location.   You   need   the   permission   of the   landowner   if   you   launch   on   foreign   territory.   Please   wear   safety   goggles   when   pressure   testing   or   launching   your   rocket.   Keep   a   safe   distance   to   the pressurized   rocket.   We   can   not   guarantee   the   accuracy,   completeness   or   feasibility   of   any   our   tutorials.      We   are   not   responsible   for   any   damage   or   harm   on objects,   animals   or   humans.   We   do   not   guarantee   that   the   information   provided   on   this   web   site   is   complete,   accurate   and   always   current.   This   applies   also to all links cited on this website points, either directly or indirectly. We are not responsible for any damage or harm to objects or individuals.
SAFETY GUIDELINES AND DISCLAIMER
REFERENCES
U.S. Water Rockets on YouTube - Ultimate Water Rocket Parachute Deploy Mechanism https://www.youtube.com/watch?v=UnwP3YXOn-I U.S. Water Rockets Website - How to construct a Radial Parachute Deploy Mechanism http://www.uswaterrockets.com/construction_&_tutorials/Radial_Deploy/tutorial.htm Aircommando Walldorf on YouTube - Fallschirmsystem el 1.0 | Review https://www.youtube.com/watch?v=7C4k3HDVM0Y Aircommando Walldorf on YouTube - Wasserraketen Tutorial: Tommy Timer https://www.youtube.com/watch?v=I7xbnTmoO4o
WHAT‘S NEXT? Take a look at our other tutorials…
English
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about our Parachute  Recovery Systems
Frequently Asked Questions (FAQ)
What‘s the failure rate of your current parachute systems? Our   Phoenix   5   Side   Deployment   System   is   very   reliable   with   a   failure   rate   of   only   3/70   (in   March   2017)   which equals   4.2%.   Two   of   the   three   failures   could   have   been   avoided   if   our   current   checklist   had   been   applied correctly.         Our   version   of   the   Radial   Deployment   System   had   a   few   issues   in   the   beginning,   but   we   were   able   to improve   the   reliability   a   lot.      Our   latest   addition   to   our   parachute   system   family,   which   is   used   in   the   „Falcon“ rockets, hasn‘t completed enough launches yet for a trustworthy valuation. Why do you (still) use a mechanical tommy timer and no electrical system? Our   current   tommy   timer   based   systems   like   Phoenix   5   and   Raketfued   RDS   are   more   reliable   than   many systems   which   are   based   on   electrical   timers   or   sensors.   A   tommy   timer   is   also   a   lot   more   affordable.   That‘s especially    relevant    because    most    failures    or    crashes    also    affect    the    parachute    system.    Last    but    not    least, electrical   systems   are   heavier   than   our   mechanical   systems.   Thus,   we   see   no   reason   to   switch   to   an   electrical system. Which altimeter do you use and where can I buy it? We   use   a   range   of   altimeters.   In   our   first   water   rocket   which   included   an   altimeter   we   used   the   “Altimax   Simply” made   by   Rocketronics    ,   but   this   altimeter   can‘t   output   the   data   in   a   table   or   chart.   That‘s   why   we   switched   to   a prototype   made   by   the   German   Aerospace   Center   DLR.   We   also   use   the      Hobbyking   Altimeter    in   many   of   our rockets. Which parachute size do I need for my rocket? That depends on its weight. Usually the recommended payload is given on the packaging or on the website. Is there any other method of building a recovery system? Yes, absolutely! You can 3D print the casing, for example. Learn more here.
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If   you   want   to   build   an   advanced   water   rocket,   and you   don’t   want   to   start   all   over   again   after   the   first flight,   we   suggest   building   a   recovery   system   for your   rocket,   which   brings   the   rocket   safely   back   to earth.    Let’s    begin    with    the    basics:    A    parachute deployment      mechanism,      the      most      common recovery    system    for    a    water    rocket,    ejects    the parachute    at    the    right    time.    That    sounds    pretty easy   but   in   fact   it   is   one   of   the   most   sophisticated tasks   when   building   a   water   rocket.   The   system   has to be small, light and reliable.
THE TOMMY TIMER
There    are    numerous    approaches    for    parachute deployment   mechanisms.   In   this   tutorial,   we   show you   how   to   build   a   mechanical   system    based   on   a Tommy    Timer .    Tommy    Timers    can    be    found    in wind-up   toys   which   are   available   in   toy   stores   and on   the   internet.   After   removing   the   case   you   can cut   off   all   protruding   parts   of   the   timer   using   pliers. You   should   also   remove   the   plastic   handle   from the   main   axel   by   repeatedly   clamping   it   in   a   vice. After   that,   bend   the   axel   using   two   sets   of   pliers. The   modified   timer   will   later   be   the   centerpiece   of the   system.   You   may   wonder   why   we   use   these mechanical   timers   and   don’t   work   with   electronic systems.     Well,     the     answer     is     pretty     simple: Mechanical   systems   are   way   easier   to   build    and repair,    are    significantly    lighter     and    a    lot    more affordable     when    compared    to    electronic    ones    this   is   especially   important   when   a   rocket   crashes and      you      have      to      build      a      new      parachute deployment   mechanism.   But   luckily,   this   shouldn’t be   the   case   all   too   often   since   the   two   systems   we want   to   show   you   in   this   video   have   already   proven their reliability  with numerous flights.
WHICH SYSTEM IS SUITABLE?
The    first    system    we    want    to    show    you    is    called Phoenix    6.    It’s    the    latest    version    of    our    Phoenix Parachute      Side      Deployment      System      and      is optimized   for   rockets   with   a   single   large   pressure vessel.   For   rockets   consisting   of   multiple   pressure vessel      segments      we      recommend      building      a Phoenix    Radial    Deployment    System.    This    system was    originally    developed    by    our    colleagues    from U.S.   Water   Rockets ,   but   we   adjusted   and   optimized it for the use with a lightweight mechanical timer.
PHOENIX 6
For     the     construction     of     the     Phoenix     6     Side Deployment      Mechanism      you      will      need      two bottles .   It   is   necessary   to   use   the   same   bottle   type you   have   already   used   for   your   pressure   vessel. Cut    off    the    bottom    of    one    of    the    bottles    using scissors   and   remove   the   thread   of   the   bottle   with   a saw.   Now   you   have   to   cut   a   big   opening    in   the cylindrical   section   of   the   bottle.   In   this   case,   the opening    is    about    10    cm    /    3.9”    wide    and    there should   be   about   3cm   /   1.2”   left   to   the   lower   edge. When    you    use    bottles    with    a    bigger    or    smaller diameter,    you    have    to    adjust    the    width    of    the opening.   The   bottle   with   the   opening   will   later   be the   case   of   the   parachute   system .   But   of   course, your   case   will   need   a   nosecone.   You   can   either   glue a   half   table   tennis   ball    on   top   with   epoxy   or   you can   use   the   nosecone   of   a   fireworks   rocket    for that.   Now   take   the   second   bottle   and   remove   both the   bottom   and   the   neck.   The   remaining   cylindrical section    will    be    separated    in    two    equally    large pieces.   One   of   these   pieces   will   be   the   parachute door . If   you   want   to   paint   your   parachute   system,   you can   do   this   now.   First,   sand   and   clean   both   the   case and   the   door.   We   recommend   using   plastic   primer before   applying   the   paint.   The   spray   paint   can   be applied   as   soon   as   the   primer   is   dry.   It‘s   maybe necessary to spray several coats. After   that,   you   can   cut   out   two   round   base   plates out   of   a   thin   plastic   plate.   You   should   be   able   to put   the   plates   into   the   system,   but   they   shouldn’t be   too   small   and   should   remain   in   place   without any   glue.   After   you   have   placed   the   plates   directly at   the   lower   and   upper   edge   of   the   opening,   you can   glue   them   in   place   using   a   hot   glue   gun.   Please be careful and don’t use too much adhesive. Now   it’s   time   to   mount   the   Tommy   Timer   you   have modified   at   the   beginning.   All   you   need   are   three small   holes   in   the   case   located   slightly   above   the lower   base   plate.   Put   the   bent   axel   of   the   timer through   the   hole   in   the   middle   and   use   a   small cable   tie   to   fasten   it.   The   parachute   door,   which   is placed   over   the   opening,   can   be   fastened   by   using a   rubber   band.   Just   mount   a   loop   slightly   under   the upper   base   plate   on   the   case.   Now   you   can   wrap the    rubber    band    multiple    times    around    the system .   Just   hook   the   rubber   band   over   the   bent timer axel. To   eject   the   parachute,   you   need   a   spring .   For   that, you   can   use   a   part   of   a   thin   walled   plastic   bottle. You   can   attach   the   bottle   piece   with   wire   on   the case   but   you   can   also   take   the   whole   cylindrical section   and   glue   it   in   place   with   a   hot   glue   gun. However,   if   you   use   this   method   you   have   to   watch out    that    the    parachute    will    pushed    out    of    the opening   and   not   to   the   side.   The   parachute   door can   now   be   attached   with   a   rubber   band   on   the parachute.  
PHOENIX RDS
But     before     we     finish     the     construction     of     the Phoenix   6   mechanism,   we   want   to   take   a   look   at the   Phoenix   RDS.   The   good   news   is,   that   it   consists of   even   less   components   than   the   Phoenix   6.   The most   important   component   is   a   thin   but   flexible plastic   cover .      You   can   use   a   document   cover   or   a thin    walled    bottle    section    for    that.    Mount    the modified   Tommy   Timer   at   one   edge   of   the   cover using   two   little   cable   ties.   On   the   opposite   edge you   can   attach   a   rubber   band   loop.   For   the   next steps,   you   will   need   a   rocket   with   multiple   pressure vessel     segments.     Wrap     the     cover     around     the connection   between   two   segments ,   then   wrap the   rubber   band   around   it   and   hook   it   on   the   timer axel.   Another   rubber   band   attached   to   the   cover and   the   nosecone   of   the   rocket   will   ensure   that   the cover   will   be   pulled   away    when   the   parachute gets   ejected.   The   Phoenix   RDS   is   now   already   on the    same    level    as    the    Phoenix    6    System,    whose construction   we   described   earlier   in   this   video.   The following steps are identical with both systems.
LAST STEPS
To   prevent   the   rubber   band   sliding   over   the   bend of   the   timer   axel,   glue   a   small   cable   tie   head    with epoxy   or   superglue   directly   at   the   bend.   Now   you can   hook   in   the   rubber   band   once   again   and   wind up   the   timer.   A   few   seconds   later,   the   rubber   band will   be   released   and   the   parachute   ejected.   Please be   very   careful   when   testing   the   system   because you   do   not   want   to   get   the   rubber   band   flick   into your    eyes.    Now,    the    only    thing    you    need    to complete   the   construction   is   a   small   trigger    which holds   the   timer   in   place   until   the   rocket   launches. Luckily   the   construction   is   fairly   simple.   You   just need   a   big   cable   tie!   Cut   the   long   part   off   so   that the   remaining   cable   tie   is   only   5cm   /   2”   long.   Now wind      up      the      timer      and      place      the      trigger underneath   the   small   cable   tie   you   used   to   attach the    timer    so    that    the    timer    can’t    start    running. Connect   the   trigger   with   wire   and   a   rope   to   your launch   pad   and   you   are   ready.   But   don’t   forget   to attach   the   parachute   and   the   system   to   your   rocket first.
Spitze 3cm / 1.2 10cm / 3.9
Wind-up toy
Modified Tommy Timer
Painted system with nosecone
Base plates
System with spring and parachute
Rubber band wrapped around the system
1) System with trigger (before launch)
2) Timer is running (launch)
3) System opens
4) Parachute is ejected
ADVANCED COMPONENT TUTORIALS RECOVERY SYSTEMS
More tutorials Advanced component tutorials TUTORIAL AS PDF DOWNLOAD IT HERE PDF BILL OF MATERIALS DOWNLOAD IT HERE PDF
To   succeed   with   the   construction   of   a   water   rocket,   you   will   have to    work    very    precisely    and    carefully.    Especially    some    of    the adhesives   are   pretty   dangerous.   Thus,   please   wear   gloves   when working   with   adhesive   or   epoxy   and   don‘t   breathe   in   the   gases.   It is    recommended    to    work    outside    whenever    toxic    gases    could develop.   The   launch   of   a   water   rocket   may   needs   permission   from the   competent   authority,   depending   on   your   location.   You   need the    permission    of    the    landowner    if    you    launch    on    foreign territory.    Please    wear    safety    goggles    when    pressure    testing    or launching   your   rocket.   Keep   a   safe   distance   to   the   pressurized rocket.    We    can    not    guarantee    the    accuracy,    completeness    or feasibility   of   any   our   tutorials.      We   are   not   responsible   for   any damage    or    harm    on    objects,    animals    or    humans.    We    do    not guarantee    that    the    information    provided    on    this    web    site    is complete,   accurate   and   always   current.   This   applies   also   to   all links   cited   on   this   website   points,   either   directly   or   indirectly.   We are    not    responsible    for    any    damage    or    harm    to    objects    or individuals.
SAFETY GUIDELINES AND DISCLAIMER
REFERENCES
U.S. Water Rockets on YouTube - Ultimate Water Rocket Parachute Deploy Mechanism https://www.youtube.com/watch?v=UnwP3YXOn-I U.S. Water Rockets Website - How to construct a Radial Parachute Deploy Mechanism http://www.uswaterrockets.com/construction_&_tutorials/R adial_Deploy/tutorial.htm Aircommando Walldorf on YouTube - Fallschirmsystem el 1.0 | Review https://www.youtube.com/watch?v=7C4k3HDVM0Y Aircommando Walldorf on YouTube - Wasserraketen Tutorial: Tommy Timer https://www.youtube.com/watch?v=I7xbnTmoO4o
WHAT‘S NEXT? Take a look at our other tutorials…
Air Command Water Rockets THIS TUTORIAL WAS TRANSLATEDWITH THE HELP OF
about our Parachute  Recovery Systems
FAQ
What‘s the failure rate of your current parachute systems? Our   Phoenix   5   Side   Deployment   System   is very   reliable   with   a   failure   rate   of   only   3/70 (in   March   2017)   which   equals   4.2%.   Two   of the   three   failures   could   have   been   avoided if    our    current    checklist    had    been    applied correctly.               Our     version     of     the     Radial Deployment   System   had   a   few   issues   in   the beginning,   but   we   were   able   to   improve   the reliability   a   lot.      Our   latest   addition   to   our parachute   system   family,   which   is   used   in the     „Falcon“     rockets,     hasn‘t     completed enough     launches     yet     for     a     trustworthy valuation. Why do you (still) use a mechanical tommy timer and no electrical system? Our    current    tommy    timer    based    systems like   Phoenix   5   and   Raketfued   RDS   are   more reliable   than   many   systems   which   are   based on    electrical    timers    or    sensors.    A    tommy timer   is   also   a   lot   more   affordable.   That‘s especially   relevant   because   most   failures   or crashes    also    affect    the    parachute    system. Last    but    not    least,    electrical    systems    are heavier   than   our   mechanical   systems.   Thus, we   see   no   reason   to   switch   to   an   electrical system. Which altimeter do you use and where can I buy it? We   use   a   range   of   altimeters.   In   our   first water   rocket   which   included   an   altimeter   we used      the      “Altimax      Simply”      made      by Rocketronics    ,   but   this   altimeter   can‘t   output the   data   in   a   table   or   chart.   That‘s   why   we switched     to     a     prototype     made     by     the German   Aerospace   Center   DLR.   We   also   use the        Hobbyking    Altimeter     in    many    of    our rockets. Which parachute size do I need for my rocket? That    depends    on    its    weight.    Usually    the recommended     payload     is     given     on     the packaging or on the website. Is there any other method of building a recovery system? Yes, absolutely! You can 3D print the casing, for example. Learn more here.
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