the balloon is not visible due to haze. cloud cover. etc. Ground radar
has been used • .nen available, ~th fair results. particularly when radar
targets are added to the flight train.
E. Fligh.t Termination Control
Due to the size and weight of the balloons and the flight gear •
the Civil Aeronautics Authority was advised oft he testing program. At a
meeting in New York an 20 .March 1947, the New York Air Space Sub-Committee
prescribed a procedure which was designed to minimize the hazard to air
traffic. Similarly, the Fort Worth Sub-Committee established a procedure
for flights made within the Fort V1orth .ttegion of the cAA. Pertinent cor-
respondence with the CAA is included in the Appendix. Part 2. Owing to
the si. ze of these cells, a very slow rate of descent should be expected
atter all ballast has been expended and the flight control devices have
ceased to operate. Thus a large balloon and several heavy pieces of
equipment might take an hour or more to descend through the levels of
air travel. Despite the extreme improbability of midair collision. it is
obviously desirable to take all possible precautions against such mishap
and current flights have the following safeguards: (1) Flights are released
on days ~hen cloud cover is forecast to be light. thus permitting visual
contact. (2) Notices to airmen are to be issued if the balloon is descending
within designated regions of dense air tra~fic. (3) To reduce the time
involved in a final descent, a special device called the "blowout patch"
has been~eveloped. This is an igniting squib which is fastened to the
side of the cell. on the equator. Sealed in with the squib, which is fired
electrically ~hen the cell descends below 20.000 feet, is a quantity of
gunpowder and magnesium. When the squib is fired. the incendiary patch
blows out, allowing a rapid escape of gas through the opening. Since the
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