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projects:jimbob:launch3 [2013/07/29 21:53] kevwalprojects:jimbob:launch3 [2013/08/07 07:41] (current) – [Predictor] kevwal
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 ====== Launch 3 ====== ====== Launch 3 ======
  
-This page tracks Launch 3, planning in progress. +This page tracks Launch 3, planning in progress, a foil balloon launch.
- +
-====== Bill of Materials ======+
  
 +==== Bill of Materials ====
  
 ===== Tracker ==== ===== Tracker ====
  
 +
 +Just the one:
 [[projects:jimbob:habtrk|HABTRK]] [[projects:jimbob:habtrk|HABTRK]]
  
 +===== Power ====
 +
 +Single Energiser Lithium AA or AAA
 +
 +  * AA - 3,000 mah, 15g
 +  * AAA - 1,250 mah, 8g
 +
 +Going to use a single AA for my first flight - the voltage drop from a AAA whilst the GPS is getting a fix is quite high and the boost converter I am using fails to maintain the voltage required to the GPS and it resets after a couple of hours in the freezer.
 +
 +===== Balloon ====
 +
 +36” Qualatex silver “foil” balloon
 +
 +Approximate weight of 37g, approximate internal volume of 0.1cu m before envelope stretching. 
 +
 +This means they can lift payloads of approx. 60g (or slightly more if you allow for stretching). However experimenters typically aim for payloads of the order of 20 - 40g per balloon in order to attempt to make them float.
 +
 +  * http://www.randomengineering.co.uk/Random_Aerospace/Balloons.html
 +
 +===== Enclosure ====
 +
 +ToDo
 +
 +===== Helium =====
 +
 +Purchased: http://www.ebay.co.uk/itm/Helium-Helium-Cylinder-Helium-Gas-Balloon-Gas-10litre-200bar-/171072782079?pt=LH_DefaultDomain_3&hash=item27d4bb7eff
 +
 +
 +===== Weight =====
 +
 +Tracker including aerial - 13.8g
 +
 +Battery including lead - 16.2
 +
 +Insulation ~ 7
 +
 +Total = 39g
 +
 +
 +
 +===== Predictor ====
 +
 +Looking through the data here: http://ukhas.org.uk/projects:microballoons:data?s[]=foil
 +
 +and modifying the predictor from here: http://ukhas.org.uk/_media/guides:burst3.xls
 +
 +with a balloon weight of 37g, a burst diameter of about 0.70m is the best estimate I could make for a 'if it bursts' flight path with a Descent rate of 5m/s.
 +
 +Based on a 39g payload, to get an ascent rate of 1m/s = 3.5g free lift
 +
 +===== Flight Document ====
 +
 +Flight Document created http://habitat.habhub.org/genpayload/
 +
 +Doc ID: c5c392ef5958c9dce8ffd58920297444
 +Document: {"type":"flight","approved":false,"name":"G7PMO Launch 2","start":"2013-08-07T00:00:00+01:00","end":"2013-08-07T23:59:59+01:00","launch":{"time":"2013-08-07T10:00:00+01:00","timezone":"Europe/London","location":{"latitude":52.3,"longitude":-0.7}},"metadata":{"location":"Wellingborough, Northamptonshire, UK","project":"G7PMO","group":"Kevin Walton"},"payloads":["e55cc3ffb42062c70087dae3d9520903"]}
 +
 +
 +==== Launch Announcement ====
 +
 +Launching Wednesday 7th August around 10am a single tracker foil launch, from a site near Wellingborough (Northants).
 +
 +Primary tracker: RFM22B based, $$HABTRK, 434.150Mhz (434138400 on my rx), USB, RTTY, 470Hz Shift, ASCII-7, 50 Baud, Parity none, 1 Stop bit
 +
 +$$HABTRK, id, time, lat, lon, alt, sats, vinmv, rfm_temp.
 +
 +Documentation is here: http://ukhas.org.uk/projects:jimbob:launch3
 +
 +Track it here: http://spacenear.us/tracker/ or http://habitat.habhub.org/mobile-tracker/
 +
 +Predictor based on Marston launch here: http://predict.habhub.org/hourly/marston/ or anywhere http://habhub.org/predict/ or http://weather.uwyo.edu/polar/balloon_traj.html
 +
 +
 +Burst predictors are linked from here: http://ukhas.org.uk/guides:balloon_data
projects/jimbob/launch3.1375134788.txt.gz · Last modified: 2013/07/29 21:53 by kevwal

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