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Results of UND Aerospace Leonid Balloon Project

Here's the result of the UND Leonid Balloon project--

Grand Forks, ND, 11/18/99--Well, last night was interesting.  I got the
last components for the balloon flight that I was responsible for built by
about
6:45 pm on Wednesday.  When I arrived at Space Sudies, tensions were
running a bit high.  The payload had turned out to be about two pounds
heavier than it was supposed to, and would be the heaviest we had
ever launched.  After some ruffled feathers were smoothed, we decided
to go with what we had (making a few provisions to dump weight if we
absolutly had to).  Reports from the BBC about 1,000 meteor per hour
observations in Europe only goaded us on, and we headed out for the
launch site about 11:00 pm CST.
	At the launch field just outside Northwood, ND, we pointed
all our vehicles at the assembly area and left the headlights (and
engines) running.  I shot some video tape of the filling operations
as we continued to monitor the weather.  The weather turned out to be
very nice the whole night, with partly clear skies and almost no
wind.  When all the helium we brought had been pumped into the balloon,
it didn't provide as much lift as we expected (possibly due to the cold
weather).  The lift was just sufficient to loft the payload as designed,
so we decided to go for it.  
	The stack consisted of: a 1200g latex weather balloon, a drogue
parachute made from part of an old bed sheet, two chemical light sticks,
the cut-down mechanism, the main parachute made from another golf
umbrella, the dust collector (which formed the lid of the gondola),
the gondola, and the tail, from which hung the audio tracking speaker,
the radar reflector, and the marker strobe light.  
	For this mission, the flight computer was programmed to activate
the cut-down at two hours.  This would release the balloon from the 
gondola.  The departing balloon lanyard was also attached to two trigger
lines: one to pull a retaining pin on the dust collector doors and
allow them to shut and seal.  The other was attached to a nylon bag
containing the main parachute.  This would pull the 'chute out of the
bag (paratrooper style) and deploy it.  The drogue 'chute was to provide
some resistance in case the balloon burst before the cut-down was 
triggered, since some tension on the lanyard was needed to deploy the
main 'chute.
	Despite predictions, after release the balloon headed
southwest.  This is actually a pretty set pattern for our flights.
It went far enough that way for the chasers to take off in hot pursuit.
The balloon then went north, then east, passing our location to the
north.  Just like previous missions, we got to wave to the chasers as
they sped by again :).
	Climbing very slowly, the balloon was only at about 14,000 feet
as it approached the airbase and restricted airspace.  I believe it 
went south of the base, and crossed over highway 2 somewhere near 
the airport (the FAA isn't looking for us yet, to my knowledge anyway).
At about 2 hours and 5 minutes mission elapsed time, the cutdown was
activated by the computer with the balloon at about 23,000 feet 
northeast of East Grand Forks.  At this point the gondola started a
rather rapid descent to the ground.  Even so, the GPS reacquired satellite
lock on the way down and relayed us one last position report at about
7,000 feet altitude.  One chaser in the area heard a strong signal on
the ground, and other chasers equipped with mobile APRS terminals
raced to the scene.  The GPS was still working, and allowed us to get
a precise position report of the package on the ground.  We found the
gondola about a half-mile into a plowed field at about 5:00 am (which
would have been impossible in the dark without the GPS signal), and
returned to Space Studies with it.
	Back at the U, a post-mortem revealed that the trigger line
that closed the dust collector had worked, but the one that was supposed
to deploy the main 'chute had broken.  The bag was still over the 'chute,
and the payload had apparently free-fallen from 23,000 feet.  Luckily for
us, the terminal velocity of a 10 pound foam box is not very high, and
the only piece of electronics that suffered visible damage was the 
cut-down device.  Our enthusiasm took a blow when we discovered that
the camcorder would not eject the tape or even rewind it, however.
There were no rattles or obviously broken parts (other than a pivot
on the viewfinder), and the mechanism may only be jammed.  Unlike the
other electronics, the camcorder (although nestled inside the foam
box), had a steel mounting bolt protruding from the tripod socket
through the bottom of the box.  This hit the ground first, likely
transfering the shock of landing directly to the camcorder (ouch!).
One of our engineering-types is going to disassemble the camcorder
today to try to extract the tape.
	If the tape shows the same thing we saw in the night sky,
there will not be much to see.  Despite amazing shows in other parts
of the world, we saw bloody zip that night.  From 12:30 am to 6:30 am
I counted about 6 meteors total.  Even sporadic meteors should do better
than that.  
	Oh well, even without getting spectacular images, we did have
a rather successful flight.  Our GPS gear has never worked better, and
the proper operation of the cut-down at least kept us from losing the
gondola.  The problems with heavy payload and less lift that ususal
can be chalked up to lessons learned.  Night operations were certainly
interesting, but I'm not in any hurry to repeat them (nor are many 
other of the group.  Sleep is, in our opinion, a Good Thing).

=========================================================================
==)----------                   |                           ----------(==
John Nordlie   N0RNB            |     Regional Weather Information Center 
nordlie@rwic.und.edu            |              University of North Dakota 
701-777-6112 / 701-777-3888 fax | PO Box 9007, Grand Forks, ND 58202-9007
http://people.aero.und.edu/~nordlie/ 

LOUIS VARRICCHIO
 Environmental Information Specialist &
 Producer/Writer, "Our Changing Planet"
  (Visit OCP-TV on the Web at: www.umac.org/ocp)
  Upper Midwest Aerospace Consortium
  Odegard School of Aerospace Sciences
  University of North Dakota
  Grand Forks, N.D. 58202-9007  U.S.A.
    Phone: 701-777-2482
    Fax: 701-777-2940
    E-mail: varricch@umac.org (in N.D.); morbius@together.net (in Vt.)

"Behind every man alive stand thirty ghosts, for that is the ratio by
which the dead outnumber the living. Since the dawn of time, a hundred
billion human beings have walked the planet Earth." -- Arthur C. Clarke

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