[aprssig] Balloon Launch Thursday maybe 10 AM[ SUCCESS!]
bruninga at usna.edu
Thu Jul 18 18:34:35 CDT 2013
We recovered it! Amazing. I was only peripherally involved and could not
take over a student project from another school, and our students have been
trying for weeks to buy a high altitude GPS, but with the Government
Sequester we cannot spend a dime, and it takes WEEKS of paper processing
through 10 different people even without the sequester!
Callsign was W3ADO-11 and chase vehicles were WB4APR-9 and USNA-2 near
Anyway, it was their risk, not mine (though since they could not even buy
their own tracker, I gave them one at the last minute (My risk$ was only
for the low-altitude tracker)…
Actually the students did pretty well. I could not resist checking EVERY
KNOT in the string, etc. that tied our balloon, to a string, to a chute,
to a chute-ring, to their cooler-payload and then hung my coke bottle
tracker below it all. The balloon filled without incident. The chain of
stuff on the string was walked down towards the payload but when the guy
let go of the string to then transfer the load to the chute. Up went the
My heart sank, since I had checked every single knot. What I did not check
was the strong metal 2” diameter Key ring at the top of the chute. Three
students were in charge of the chute which had flown several times before
successfully. What I did not know was that no one checked the chute ring.
Apparently in all past flights, the ring was tied through the chute to a
big Styrofoam ball. The ball inside the chute was attached to the key ring
above the chute and then to the balloon. Turns out, the students had seen
a ball, but discarded it.. with the ball gone, the only thing holding the
ring on the top of the chute was just a knot under a hole in the nylon! And
a piece of duct tape on the top!!
Anyway, thank heavens for a spare balloon and spare tanks!
The GPS2 (OEM version) on the TT3 worked fine. Its last vertical altitude
was 77,894 feet. Then there was no change in altitude or position for 20
minutes as it peaked, and burst and then we got it on the way down (8 miles
away) at 73,930 feet. Track was great , but only to 67,959 where it stuck
for 27 minutes!
Oh, and the overall track was only about 12 miles or less, because winds
were non existant and air temps were 98F and well over 105 with the
humidity. The air was so thick you could cut it with a knife…
A big sigh of relief came out as it started tracking again at 9026 feet 6?
miles away and in another 10 minutes one car was able to SEE the package
land in a corn field.
The loud 80 dB squaker made it easy to find in the 10’ tall corn. The hard
part was to get the army of eager students to STOP and LISTEN. Then we
walked right to it.
Photos someday.. !
Oh, My method of maintain temperature in the outside -65F is to simply put
my APRS stuff in a clear plastic water bottle and let the sun keep it
warm. The package is very light. And it floats, and it meets the density
requirements for inadvertent impact.
Their main payload (a small CUBESAT) used the classic method of placing it
in a Styrofoam cooler with 6 hand warmers. When we recovered it, the
cubesat was so hot the cooler had to be emptied and allowed to cool before
one could even touch the cubesat with bare hands.
But instead of my few party balloon flights, they had a 1500g balloon with
8 POUNDS of free lift! (That lifted a full Milk Jug as the test weight).
*From:* Robert Bruninga [mailto:bruninga at usna.edu]
*Sent:* Wednesday, July 17, 2013 6:57 PM
*To:* aprssig at tapr.org
*Cc:* aprs at yahoogroups.com; wa3nan at lists.nasa.gov; bruninga at usna.edu
*Subject:* Balloon Launch Thursday maybe 10 AM
Launch from Lancaster PA, mild winds.
Should go up to 100k feet and then come down not far from launch. Be heard
across 15 states.
Though it is a non high altitude GPS and FIX will be stuck above 18k feet
until it comes back down.
Callsign is W3ADO-11 and it will be on 144.39
If anyone KNOWS that a Tinytrack3 and GPS2 from Byonics will **not**
re-aquire when it comes back below 18k feet please let us know NOW.
Thanks The rest of the payload costs $10,000 and we don’t want to lose
it. It is a different schools project that noone else can access, so I
wont bother with details.
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