[aprssig] [aprsisce] Transatlantic balloon attempt (ballast?)

[Bob Bruninga]

>   The descent rate right now is consistent with what I
>   have seen from zero pressure balloons
>   The big question is, how is their ballast-release
>   controlled? 

Robert,

Can you elaborate?  Is it possible to do a constant pressure balloon mission without ballast release?  We are going to fly a 50g payload any time now on 6 three foot mylar party balloons at about 22,000 feet (the max possible without even an ounce of payload is only 35,000 feet due to the weight of the balloons).

These balloons seem to have a very low loss rate, and they also can stand some overpressure..  Can we survive without active ballast release?  We are going to carry some water and let it evaporate, but do not want to be totally dependent on such an untried system.

Also I am concerned that I never heard their HF beacons even though I was less than 300 miles away and well inside the 400 mile range.  If anyone did hear the HF beacon, I'd like to hear more about it.  That will be all we have on ours.

Bob, WB4aPR