Short answer: by inflating the balloon only partially.
As the balloon goes higher, atmospheric pressure decreases and thus the balloon grows bigger and bigger, eventually to the point of bursting. By inflating the balloon partially you give the smaller amount of contained gas more room to expand, hopefully reaching a stable flotation height before bursting. That comes at the cost of decreased payload and climb rate, obviously. Pardon me asking this question as it only relates to amateur satellites in a small way as the packages I refer to don't achieve escape velocity.
Over the years I've followed the work being done regarding flying radio packages on balloons.
I'm familiar with the scenario of a balloon carrying a package that will go to a predetermined altitude, bursting then returning to the ground.
With the advent of the round-the-world experiments with small party balloons, how do project organizers keep such equipment in the jet stream so that they travel long distances without the equipment going so high that the balloon bursts?
Dave Marthouse N2AAM dmarthouse@gmail.com _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb