roswell

Flight 12 was designed to overcame the difficulties encountered
in flights 8 and 11, and, by the use of a thin tear-drop balloon (General
Mills balloon) to earn~ the load to a higher altitude than flight 10.
To guarantee a predetermined constant ballast flaw, the manual ballast
valve we.s added to the flight train. The minimum pressure switch
replaced the fixed pressure switch to activate the automatic ballast
valve, whether or not a predete~ined activation altitude was reached.
Figure 46 shows the train; figure 47 shows the time-altitude curve, Which
exhibits a marked departure from the ideal. The minimum pressure switch
failed to operate or operated near surface pressure, effectively preventing
the operation of the automatic ballast valve. The manual ballast valve did
not provide sufficient rlow to prevent the gradual descent of the balloon.
Finally, the heavy load necessitated almost complete inflation of the
balloon at the surface. lhis distention permitted continual mixing of
air through the open bottom of the balloon. Instead of reaching the pre-
calculated 38,000 feet maximum altitude, this flight had a peak of 14,000
feet from which it slowly descended. Since the blowout patch was set to
act upor. descent to 20,000 feet, it also failed to operate.
Five of the succeeding flights (nos. 13, 14, 15, 16 and 20) had as
a prime objective the development of a satisfactory a.ppendix to overcome
the loss of buoyancy due to mixing during launching and ascent. fhe types
considered have been discussed in Section II, Part A of this· report and
the (two foot) appendix stiffened with battens, Which was finally evolved,
is shown in figure 5. Figures 48, 49 and 50 show the time-altitude curves
for these flights. Either short flight or limited radio reception curtailed
the trajectory data.
In flight 19, the danger to perscrmel of the blowout patch was
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