During the manufacturing process, the balloons were laid out on long, thin
tables. One section of the balloon would be sealed by running a heat sealer the
length of one edge. That was then attached to the next section, sealed, and so on…
until the balloon was done. The polyethylene was so fragile that the “balloon
girls” worked in stocking feet and checked their fingernails every morning to
make sure nothing on them could tear the balloons.
Winzen created a number of polyethylene balloons that he sold to the U.S. Army
and Navy, including the Skyhook balloon and the Air Force’s Project Man High. In
1972 he developed the Winzen Research Balloon. This achieved the record for the
highest unmanned balloon flight, reaching 51.8 km (170,000 ft) above Chico, CA.
The introduction of StratoFilm in 1965 solved a number of problems related to
materials that had plagued the balloon community until that time. As payloads and
float altitudes increased over the years, the balloons became much larger. In the
late 1970’s and early 1980’s catastrophic failures with stratospheric balloons
began to erode the confidence of their scientific users. At the same time, balloon
manufacturers intensified their efforts to produce the high quality film essential
for a reliable, low-cost platform that would operate in the stratosphere. Winzen
took the approach of blending newly developed resins such as linear low density
polyethylene with other polymers to achieve the desired properties. The resulting
film, called StratoFilm 372 (a.k.a. Winzen SF-372) enjoyed a 100% successful
flight record for over three years.
Fig. 3.1 “Balloon girls” at Winzen. Photo courtesy of the General Mills archives
3.1 Balloon Envelopes 29
tables. One section of the balloon would be sealed by running a heat sealer the
length of one edge. That was then attached to the next section, sealed, and so on…
until the balloon was done. The polyethylene was so fragile that the “balloon
girls” worked in stocking feet and checked their fingernails every morning to
make sure nothing on them could tear the balloons.
Winzen created a number of polyethylene balloons that he sold to the U.S. Army
and Navy, including the Skyhook balloon and the Air Force’s Project Man High. In
1972 he developed the Winzen Research Balloon. This achieved the record for the
highest unmanned balloon flight, reaching 51.8 km (170,000 ft) above Chico, CA.
The introduction of StratoFilm in 1965 solved a number of problems related to
materials that had plagued the balloon community until that time. As payloads and
float altitudes increased over the years, the balloons became much larger. In the
late 1970’s and early 1980’s catastrophic failures with stratospheric balloons
began to erode the confidence of their scientific users. At the same time, balloon
manufacturers intensified their efforts to produce the high quality film essential
for a reliable, low-cost platform that would operate in the stratosphere. Winzen
took the approach of blending newly developed resins such as linear low density
polyethylene with other polymers to achieve the desired properties. The resulting
film, called StratoFilm 372 (a.k.a. Winzen SF-372) enjoyed a 100% successful
flight record for over three years.
Fig. 3.1 “Balloon girls” at Winzen. Photo courtesy of the General Mills archives
3.1 Balloon Envelopes 29