■ FIGURE 13. My highest altitude photog (near 87,000 feet).
It was a hazy morning over Nebraska, as you can see.
at end of this month’s column); and the last, a cube covered
in MLI and a black jacket of construction paper. As you can
see, they cooled close to the same rate initially. But as
they neared the stratosphere after 35 minutes of flight, their
temperatures deviated widely from one another. At balloon
burst ( 83 minutes into the mission), they chilled to nearly
the same temperature after 10 minutes.
THE GREAT PLAINS SUPER LAUNCH
The largest amateur radio, high altitude balloon
(ARHAB) event is the Great Plains Super Launch (GPSL).
Eleven weather balloons were launched on July 7th in
Grand Island, NE, the location of GPSL 2007. The Central
Nebraska Near Space Project (CNNSP) hosted the two-day
conference this year in their home town. Friday was spent
in discussions, with several near space groups giving
presentations on the art and science of their near space
programs. There were discussions on air density and its
effect on a balloon’s coefficient of drag, flight computers,
balloon release mechanisms, and meteorology.
Along with the presentations there was lots of socializing, especially over lunch and dinner. The new attendees
were presented with a ton of information. One of this year’s
sponsors was Nuts & Volts Magazine (thanks guys). But the
best was Saturday morning. That’s when we filled and
launched our near spacecraft.
DePauw and Taylor Universities were there along with
amateur groups from Kansas, Nebraska, Idaho, Colorado,
Oklahoma, and Maine. The balloon filling took place early
in the morning so the balloons could be launched before
the surface winds picked up.
For additional insurance though, we filled the balloons
behind a row of organic wind blockers (otherwise known as
tall trees in Nebraska). I really have to hand it to Roger and
CNNSP for the great job they did finding a conference
center and launch site. Figure 13 shows a photograph from
Every near spacecraft was recovered after they landed
except for one. We lost contact with its tracking capsule
shortly after lift off. I had to leave for Idaho just after lunch
BRIEF NOTE ABOUT MULTILAYER
One of the best insulators is the Dewar flask
(which is the same thing as a thermos bottle). Usually
though, spacecraft cannot carry a glass thermos to
insulate themselves. So they’re covered in a fabric
version of this called MLI. I make my MLI with three
alternating layers of space blanket (aluminized Mylar)
and scrim (plastic wedding veil material). In a good hard
vacuum, this stuff will work great. But in near space with
its near vacuum, it’s not nearly as effective. But it still
beats launching a glass thermos bottle on a balloon.
on Saturday, but most of the groups stayed around for an
informal dinner on Saturday evening. I hear this dinner was
very successful and will be included in GPSLs in the future.
There’s one more super launch planned for this year
and several for 2008. The next GPSL will be held by Near
Space Ventures in Kansas City, MO. You can find the date
and other information at the Super Launch website at
http://superlaunch.org. I hope to see you next year at one
of the super launches.
Onwards and Upwards
Your Near Space Guide NV
September 2007 25