page_title: Skyhook balloon
section_title: Project Skyhook
hierarchical_section_title: Skyhook balloon / Project Skyhook
caption_attribution_description: English: US Navy photo caption: In the late 1940s, Project Skyhook balloons provided a stable vehicle for long duration observations at altitudes in excess of 100,000 feet. Balloons, long used for collecting meteorological data, now offered the opportunity of collecting highly specialized information and photographs. This photograph shows Skyhook Ballon 93 leaving the deck of the USS Norton Sound (AV-11) on 31 March 1949. (U.S. Navy Photo RELEASED - 11/7/2003)
context_page_description: Skyhook balloons were high-altitude balloons developed by Otto C. Winzen and General Mills, Inc. They were used by the United States Navy Office of Naval Research in the late 1940s and 1950s for atmospheric research, especially for constant-level meteorological observations at very high altitudes. Instruments like the Cherenkov detector were first used on Skyhook balloons.
context_section_description: In the late 1940s, Project Skyhook was conceived of as a means by which plastic balloons could be used to transmit or send instruments into the stratosphere to conduct research. This project carried forward work from an earlier project, Helios, that General Mills and Jean Piccard initiated to use arrays of giant plastic balloons to carry humans aloft.
  Balloons, long used for collecting meteorological data, now offered the opportunity of collecting highly specialized information and photographs. The first Skyhook balloon was launched on September 25, 1947. The balloon was developed by the Aeronautical Division of General Mills. It carried a 63 pounds (29 kg) payload of nuclear emulsion to over 100,000 feet (30,000 m). At low level immediately after launch, the lifting gas (hydrogen or helium) in the balloons formed a small bubble at the top of the envelope, resulting in the balloon having a "limp" look. At the lower air pressure at higher altitudes, the gas expanded and eventually filled the whole envelope forming a sphere or ovoid. In some models the balloons could reach diameters of more than 30 m.
  In the succeeding 10 years, over 1,500 Skyhook flights were made for investigations supported by the ONR and for European scientists. These flights were made from locations in the United States, Canada, and naval vessels in the Atlantic, Pacific, Caribbean, and Arctic waters. Both Winzen Research and General Mills participated in these launchings, and in later years, the Atomic Energy Commission joined ONR in support of Project Skyhook.
  Among significant flights, Project Skyhook launched the first successful three-balloon cluster in 1948. Then in 1949 the first shipboard Skyhook launch took place. It was followed by nearly 300 shipboard launchings over the next 10 years.
  The first manned plastic balloon flight under ONR contract took place in 1949. Project Rockoon, in 1952, featured a Skyhook balloon that released small Deacon rockets at about 70,000 feet (21,000 m) above arctic waters.
  One of the first known attempts to carry out an astrophysical measurement from a plastic balloon occurred under the Skyhook program on June 30, 1954. During the solar eclipse on that date two Skyhook balloons were launched by Winzen Research with camera gondolas employing simple orientating systems. The objective was to photograph the eclipse from high altitude. Varied photographic equipment was carried and aimed at the Sun to obtain full coverage for the total period of totality.
  On September 7, 1956, the University of Minnesota launched a giant Mylar balloon (developed by the G. T. Schejeldahl Corporation of Northfield, MN) to set an unofficial balloon altitude record of 145,000 feet (44,000 m) for unmanned balloons. In 1957 the US Navy began an operational aerology system known as Transosonde (trans-ocean sounding), consisting of almost daily balloon flights across the Pacific Ocean from Japan.
caption: Skyhook balloon leaving the deck of the USS Norton Sound (AVM-1) on March 31, 1949.
exif: {"Image Orientation": "Horizontal (normal)", "Image XResolution": "150", "Image YResolution": "150", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop 7.0", "Image DateTime": "2003:11:07 14:09:28", "Image ExifOffset": "156", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "294", "Thumbnail JPEGInterchangeFormatLength": "5749", "EXIF ColorSpace": "Uncalibrated", "EXIF ExifImageWidth": "695", "EXIF ExifImageLength": "818"}