Re: [GPSL] found after over 1 year
- The reception of the broken transmitter stopped after touchdown. We
calculated, that it will suck the battery dry. We hoped for that
beacon transmitter, but if you look at the video, there is a high
chance, that the antenna was sheared off during descent or that the
tuning capacitor broke away during landing. We did not get any
reception when we searched by plane, even that we went very close to
it (comparing the GPS track of the search with the landing location).
All the APRS data is on the data site:
From that data I calculated the ascent rate. As far as I remember we
had over 1kg of excess lift at takeoff.
On Mon, Oct 1, 2012 at 3:45 AM, Mike Manes <mrmanes@...> wrote:
> Hi Ralph,
> Congratulations on the good luck to have been the beneficiary of a good
> Samaritan ... err .... Pole :=). Could have been worse.
> BTW, when and from where did you launch, and what was your beacon
> callsign? Was it I-gated to aprs.fi?
> Since your beacon xmtr was keyed up full time, recovery might have
> been effected using mobile DF techniques.
> A constant ascent rate is fair assumption for initial ascent rates of
> 1000+ ft/min. There is a slight dip in ascent rate typically in the
> 40 - 70 K' range due to airflow separation from the lower hemisphere
> of the balloon envelope, but that dip is smaller than errors in pre-
> launch ascent rate estimates.
> If you have the balloon size, neck load and neck lift data, you can
> use LiftWin 041 to estimate ascent rate and burst altitude. That Windoze
> app is downloadable from a link on eoss.org.
> 73 de Mike W5VSI
> On 9/30/12 5:04 AM, dampguy wrote:
>> Hello - my first post here
>> we launched a twin balloon mission last year in August at the Chaos
>> Communication camp. The payload was an APRS tracker, a short wave radio
>> beacon, a 1080P video cam, 2 Magnetometers, pressure and temperature
>> sensors, all controlled by an Atmel Microcontroller.
>> The sad thing was that in about 41000 feet, we lost the APRS. The
>> transmitter of the APRS stayed turned on and transmitted only noise.
>> So we lost the mission... All search attempts were futile. We even took
>> off in an airplane two times to try to find the radio beacon.
>> Well - after over one year, some nice Poles found the package hanging in a
>> tree while chopping wood. My phone number was on the package, together with
>> a logo from the Chaos Camp. I could not believe the information. Well, we
>> put all the data we have online (incl. the video) on
>> There is a link to most of the data (sorry, but its in German) and some
>> panoramic pictures we created out of the video.
>> I have a question: Does anybody have data how the climb rate changes over
>> altitude? According to my calculation we could have hit about 125000 feet,
>> but that assumes a constant climb rate.
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