Embedded Files
Treecat in Near Space Project
Groups: The Royal Manticoran Navy and North Carolina Near Space
This project is to launch a plush animal toy into near space. The recovered “treecat” and the camera/images will be used as part of a charity fund raising effort for Big Cat Rescue.
Post Flight:
Liftoff was late due to delays in ground prep. The SPOT took a long while to get a fix and transmit a position. Then we did not have a big enough adjustable wrench for the cylinder fittings. this was remedied by a quick trip to the nearest hardware store (Home Depot) Final lift off was at 11:05 am from Horseshoe Park. I calculated it afterward at @ 4m/s and with winds of @8mph at ground level it was a somewhat more horizontal than vertical launch. The track was SE until it rose above the surface winds and then it tracked back NW on almost a direct reciprocal of its flight path. We were able to sight and get pictures of it around 25k ft from a mile or so from the launch site. It continued NW to near Emporia Va were it reached peak altitude of just over 86K ft.
Descent was quick and the package landed just east of Emporia in a stand of 50-60ft pines. With a 32ft ladder and 30 extendable painters pole we were able to recover the capsule just before darkness at around 6pm.
Other than the ascent rate the predictions from Totex Balloon Burst Estimator – by Steve Randall were accurate and I feel like it was a lack of helium from the 110 cylinder. Since this is a “consumer” cylinder we may be seeing some dilution of the helium or a fill based on a fixed price rather than quantity. This is not an issue for flights that are well under the 4lb limit but for flights that are trying to achieve maximum altitude or are closer to our 3,5 lb weight they may want to consider a industrial cylinder.
Equipment performance:
Video: We flew a Vivitar dvr480 helmet cam. It ran on 2 AAA batteries and we got 3hr39 min of video using Energizer Ultimate Lithium batteries. It was a longer flight than planned so we did not get it to burst altitude but I figure it was still filming at 80k ft. It was on an arm outside the capsule so it was as cold as any camera will get at that altitude.
Still camera: I think the still pictures gathered are more interesting, but part of that is a factor of camera angle. Not much changes quickly at higher altitude so 30 secs between pics seems to be a good rule of thumb. We ran a Canon PowerShot A1000 IS off 2 AA Energizer Ultimate Lithium batteries and it was still taking pictures after we recovered it…with flash on auto.(oops!) It ran the a1000-100a-1.1.0-2091_ALPHA CHDK release and ult_intrvl.bas script both needed tweaks to make them work with this camera. We had 719 still pictures.
Treecats In Near Space project - Specs and sources
Rig description
Balloon - Kaymont 600g closed with 2 zip ties… did not cut ends
Parachute - 3ft nylon suspended @6 ft below balloon via 1/4” cord that had a nylon loop for the ballon neck to be doubled over.
SPOT - in small lock lid box just under balloon. @ 5-6ft of cord to the payload box.
Payload Box - @ 14”Hx17”lx12”w strofoam Cooler painted with acrylic watercolors for visibility. 3/4” PVC struts. total length 30” for external camera mounting crossbraced internal to the box with additional PVC and + joint to prevent rotation. closed cell rigid packing foam used as spacers and bracing. Salvaged from commercial harddrive shipping container. AS100 Is still camera / APRS unit and treecat internally and Vivitar mounted extenally. J-pole anntenna for APRS dripped through box. 1/2” nylon ribbon harness for suspension and securing payload box. Duct tape to seal and secure.
Equipment
Payload - 3.5 lb total weight
Camera - Purchased
Treecat - Code name Apogee - Adopted
32MB SDHC card - Purchased - maybe only 4GB usable
Parachute - On Loan from NCNS (Rodney)
Balloon - Kaymont 600g - arrived
Rigging - done
APRS tracker - Rodney to loan “old” rig - 8”x8”x1/2” CONFIRMED
APRS antenna + connectors Rodney to loan - We actually flew Tanners J-pole dropped through the hole in the bottom.
batteries for APRS tracker - 8xAA Lithium - Purchased
SPOT - Tim W has agreed to rent the Spot for the launch. we flew this attached higher up the rig just under tha parachute in a small Lock and lock box.
Ground Equipment
Launch Stuff
Helium - 110 cylinder from Helium Express in Garner - JRG to pick up 11/16
Filler rig - 11/12 - Chris Gorski to dig through boxes at his house
Chase Stuff
APRS radio receiver
Handheld GPS
Magellan GPS300
Binoculars
Retrieval Stuff
Ladder
Bow/arrow or slingshot - JRG to bring Bow/Arrows & Line
Rope/string - JRG
Launch
Launch Date = 11/17/2012
Place = Horseshoe Farm Park in North Raleigh - N 35.884321 W 78.536625
Schedule:
Meet at 8:00 AM
Launch at 10:00 AM
Retrieve at 1:00 PM - 6 PM
Return to park
Chase team:
John Gahrmann (TRMN)
Alan Porter
Tanner Lovelace
Rodney Radford
Jack Warren (TRMN)- starting in Greenville
Dan Walker (TRMN)
John Kane (TRMN)
Victoria Gahrmann (TRMN)
Publicity
Twitter updates? @ncnearspace
Published Google map of SPOT data?
APRS.fi
Predictions
11/12 prediction: forecast for saturday 17th: 59° Partly cloudy skies. Sunrise: 6:53 a.m. Chance of precip: 10% Wind: NE at 5-10 mph, balloon_traj: 36.18 degrees north, 77.87 degrees west, 96 meters. 37.1 nautical miles, 69 degrees magnetic from the initial position. habhub.org/predict Lat: 36.1248 Lon: -78.0236 Range: 54.2km, Flight Time: 2hr11
11/15 predictions: weather is essentially unchanged, balloon_traj: 36.68 degrees north, 77.78 degrees west, 96 meters. 60.1 nautical miles, 45 degrees magnetic from the initial position places todays prediction in VA between South Hill and Emporia. habhub.org/predict Lat: 36.2542 Lon: -77.8939 Range: 70.6km, Flight Time: 2hr19
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