Stratobowl
Encyclopedia
The Stratobowl is a compact natural depression
within the limits of Black Hills National Forest
in South Dakota
, south-west of Rapid City
. In 1934–1935 it housed a stratospheric
balloon
launch site, initially known as Stratocamp, sponsored by the National Geographic Society
and the United States Army Air Corps
. In 1956–1959 the site was reused by the United States Navy
Stratolab project.
that nevertheless set an altitude record of 72178 feet (21,999.9 m), the sponsors redefined their primary objectives from record-setting to scientific research and tests of new navigation instruments. Air Corps Capt. Albert William Stevens
, Capt. Orvil Arson Anderson
and Maj. William E. Kepner were selected to fly the Explorer. Kepner and Anderson, experienced balloonists, were in charge of locating a suitable launch site. According to Kepner, an ideal site would be a crater or canyon
, a clear grassy valley encircled with rocky ridges high enough to shield the tall balloon from any wind. Ideally, the launch site it would have a high-voltage electric line, road and rail access, "and a trout
stream". Kepner and Anderson eventually located their dream canyon near Rapid City, South Dakota
. City officials, fascinated by the expected publicity campaign, agreed to build a road and electric line.
Anderson directed construction of a temporary village, housing over a hundred personnel, with the help of the South Dakota National Guard
and the army's 4th Cavalry Regiment. The central pad, 200 feet in diameter, was cushioned with sawdust to protect the fabric of the balloon as it was spread on the ground prior to inflation. Preparation for flight was regularly reported by the national press. Explorer lifted off at 6:45, July 28, 1934, an event broadcast live over the radio and watched by 30,000 spectators on site. After 7 hours in flight the pilots noticed holes torn in the bottom of the gas bag; quickly losing gas, the balloon plunged into an uncontrolled dive, its gas bag disintegrating as the balloon picked up vertical speed. At 5 thousand feet the remaining hydrogen exploded, sending the gondola in a free fall. According to Ryan, the pilots managed to bail out after the explosion, Kepner at a bare 500 feet altitude; according to Shayler, they bailed out before the explosion; all three survived uninjured. Later it turned out that the Explorer missed a world record by 624 feet. The accident was linked to folds in the balloon's fabric that put it under extreme stress as the balloon expanded in stratosphere.
The NGS and Air Corps vowed to launch a new balloon in June 1935, but the new helium
-filled Explorer II was not ready until November. Watched by 20,000 spectators, Explorer II lifted off at 8:00 November 11 and reached a new record height of 72395 feet (22,066 m). Anderson, Kepner, and Stevens became the first men to view the Earth's curvature
.
and Project Strato-Lab launches were made from the man-made crater of an iron mining pit near Crosby, Minnesota
, and, if weather allowed, from Fleming Field in South St. Paul, Minnesota
. The Stratobowl was a backup location. There was one Stratobowl launch in 1956, three in 1958, and seven in 1959. On November 8, 1956, the Strato-Lab I gondola lifted Malcolm Ross
and M. L. Lewis from the Stratobowl to a world altitude record for manned balloon flight of 76000 feet (23,164.8 m). The purpose of the flight was to gather meteorological, cosmic ray, and other scientific data necessary to improve safety at high altitudes. The most publicized flight, Strato-Lab IV piloted by Malcolm Ross and Charles B. Moore
, lifted off from Stratobowl on November 28, 1959, reached an altitude of 81000 feet (24,688.8 m), and landed safely in Kansas
after 20 hours in the air. The purpose of the flight was to perform spectrographic analysis of the planet Venus with minimal interference from the Earth's atmosphere.
Depression (geology)
A depression in geology is a landform sunken or depressed below the surrounding area. Depressions may be formed by various mechanisms.Structural or tectonic related:...
within the limits of Black Hills National Forest
Black Hills
The Black Hills are a small, isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, USA. Set off from the main body of the Rocky Mountains, the region is something of a geological anomaly—accurately described as an "island of...
in South Dakota
South Dakota
South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over...
, south-west of Rapid City
Rapid City, South Dakota
Rapid City is the second-largest city in the U.S. state of South Dakota, and the county seat of Pennington County. Named after Rapid Creek on which the city is established, it is set against the eastern slope of the Black Hills mountain range. The population was 67,956 as of the 2010 Census. Rapid...
. In 1934–1935 it housed a stratospheric
Stratosphere
The stratosphere is the second major layer of Earth's atmosphere, just above the troposphere, and below the mesosphere. It is stratified in temperature, with warmer layers higher up and cooler layers farther down. This is in contrast to the troposphere near the Earth's surface, which is cooler...
balloon
Balloon
A balloon is an inflatable flexible bag filled with a gas, such as helium, hydrogen, nitrous oxide, oxygen, or air. Modern balloons can be made from materials such as rubber, latex, polychloroprene, or a nylon fabric, while some early balloons were made of dried animal bladders, such as the pig...
launch site, initially known as Stratocamp, sponsored by the National Geographic Society
National Geographic Society
The National Geographic Society , headquartered in Washington, D.C. in the United States, is one of the largest non-profit scientific and educational institutions in the world. Its interests include geography, archaeology and natural science, the promotion of environmental and historical...
and the United States Army Air Corps
United States Army Air Corps
The United States Army Air Corps was a forerunner of the United States Air Force. Renamed from the Air Service on 2 July 1926, it was part of the United States Army and the predecessor of the United States Army Air Forces , established in 1941...
. In 1956–1959 the site was reused by the United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...
Stratolab project.
Explorer balloons
In 1934 the NGS and Air Corps co-sponsored the Explorer, a manned high-altitude balloon capable of stratospheric flight. After the crash of the Soviet Osoaviakhim-1Osoaviakhim-1
Osoaviakhim-1 was a record-setting, hydrogen-filled Soviet high-altitude balloon designed to seat a crew of three and perform scientific studies of the Earth's stratosphere. On January 30, 1934, on its maiden flight which lasted over 7 hours, the balloon reached an altitude of...
that nevertheless set an altitude record of 72178 feet (21,999.9 m), the sponsors redefined their primary objectives from record-setting to scientific research and tests of new navigation instruments. Air Corps Capt. Albert William Stevens
Albert William Stevens
Albert William Stevens was an officer in the United States Army Air Corps, balloonist and aerial photographer.-Biography:He was born on March 13, 1886 in Belfast, Maine....
, Capt. Orvil Arson Anderson
Orvil Arson Anderson
General Orvil Arson Anderson was a pioneer balloonist. In 1935 he and Albert William Stevens won the Mackay Trophy when they set a record of 72,395 feet in their balloon.-Biography:...
and Maj. William E. Kepner were selected to fly the Explorer. Kepner and Anderson, experienced balloonists, were in charge of locating a suitable launch site. According to Kepner, an ideal site would be a crater or canyon
Canyon
A canyon or gorge is a deep ravine between cliffs often carved from the landscape by a river. Rivers have a natural tendency to reach a baseline elevation, which is the same elevation as the body of water it will eventually drain into. This forms a canyon. Most canyons were formed by a process of...
, a clear grassy valley encircled with rocky ridges high enough to shield the tall balloon from any wind. Ideally, the launch site it would have a high-voltage electric line, road and rail access, "and a trout
Trout
Trout is the name for a number of species of freshwater and saltwater fish belonging to the Salmoninae subfamily of the family Salmonidae. Salmon belong to the same family as trout. Most salmon species spend almost all their lives in salt water...
stream". Kepner and Anderson eventually located their dream canyon near Rapid City, South Dakota
Rapid City, South Dakota
Rapid City is the second-largest city in the U.S. state of South Dakota, and the county seat of Pennington County. Named after Rapid Creek on which the city is established, it is set against the eastern slope of the Black Hills mountain range. The population was 67,956 as of the 2010 Census. Rapid...
. City officials, fascinated by the expected publicity campaign, agreed to build a road and electric line.
Anderson directed construction of a temporary village, housing over a hundred personnel, with the help of the South Dakota National Guard
South Dakota National Guard
The South Dakota National Guard is part of the South Dakota Department of Military & Veterans Affairs.It consists of the:*South Dakota Army National Guard ** Joint Forces Headquarters** 196th Maneuver Enhanced Brigade** 196th Regional Training Battalion...
and the army's 4th Cavalry Regiment. The central pad, 200 feet in diameter, was cushioned with sawdust to protect the fabric of the balloon as it was spread on the ground prior to inflation. Preparation for flight was regularly reported by the national press. Explorer lifted off at 6:45, July 28, 1934, an event broadcast live over the radio and watched by 30,000 spectators on site. After 7 hours in flight the pilots noticed holes torn in the bottom of the gas bag; quickly losing gas, the balloon plunged into an uncontrolled dive, its gas bag disintegrating as the balloon picked up vertical speed. At 5 thousand feet the remaining hydrogen exploded, sending the gondola in a free fall. According to Ryan, the pilots managed to bail out after the explosion, Kepner at a bare 500 feet altitude; according to Shayler, they bailed out before the explosion; all three survived uninjured. Later it turned out that the Explorer missed a world record by 624 feet. The accident was linked to folds in the balloon's fabric that put it under extreme stress as the balloon expanded in stratosphere.
The NGS and Air Corps vowed to launch a new balloon in June 1935, but the new helium
Helium
Helium is the chemical element with atomic number 2 and an atomic weight of 4.002602, which is represented by the symbol He. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table...
-filled Explorer II was not ready until November. Watched by 20,000 spectators, Explorer II lifted off at 8:00 November 11 and reached a new record height of 72395 feet (22,066 m). Anderson, Kepner, and Stevens became the first men to view the Earth's curvature
Curvature
In mathematics, curvature refers to any of a number of loosely related concepts in different areas of geometry. Intuitively, curvature is the amount by which a geometric object deviates from being flat, or straight in the case of a line, but this is defined in different ways depending on the context...
.
Strato-Lab balloons
In the 1950s, Project ManhighProject Manhigh
Project Manhigh along with Project Excelsior was a pre-Space Age military project that took men in balloons to the middle layers of the Earth’s stratosphere.-History:...
and Project Strato-Lab launches were made from the man-made crater of an iron mining pit near Crosby, Minnesota
Crosby, Minnesota
As of the census of 2000, there were 2,299 people, 989 households, and 554 families residing in the city. The population density was 755.0 people per square mile . There were 1,081 housing units at an average density of 355.0 per square mile...
, and, if weather allowed, from Fleming Field in South St. Paul, Minnesota
South St. Paul, Minnesota
South St. Paul is a city in Dakota County, Minnesota, immediately south and southeast of the city of Saint Paul, Minnesota. It is also southeast of West St. Paul, Minnesota. The population was 20,160 at the 2010 census. It is notable as one of the historic major meat packing cities in the United...
. The Stratobowl was a backup location. There was one Stratobowl launch in 1956, three in 1958, and seven in 1959. On November 8, 1956, the Strato-Lab I gondola lifted Malcolm Ross
Malcolm Ross (balloonist)
Malcolm D. Ross was a Captain in the United States Naval Reserve , an atmospheric scientist, and a balloonist who set several records for altitude and scientific inquiry, with more than 100 hours flight time in gas balloons by 1961. Along with Lieutenant Commander Victor A...
and M. L. Lewis from the Stratobowl to a world altitude record for manned balloon flight of 76000 feet (23,164.8 m). The purpose of the flight was to gather meteorological, cosmic ray, and other scientific data necessary to improve safety at high altitudes. The most publicized flight, Strato-Lab IV piloted by Malcolm Ross and Charles B. Moore
Charles B. Moore
Charles B. Moore, Jr. was an American physicist, engineer and meteorologist, known for his work with gas balloons...
, lifted off from Stratobowl on November 28, 1959, reached an altitude of 81000 feet (24,688.8 m), and landed safely in Kansas
Kansas
Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...
after 20 hours in the air. The purpose of the flight was to perform spectrographic analysis of the planet Venus with minimal interference from the Earth's atmosphere.
See also
- WasserkuppeWasserkuppeThe Wasserkuppe is a high plateau , the highest peak in the Rhön Mountains within the German state of Hessen. Between the first and second World Wars, during the era of the so-called Golden Age of Aviation, great advances in sailplane development were made there.Remark: The German wording takes its...
, a similar bowl-shaped natural landform in Germany, associated with historic aviation activity
External links
- History of the Stratobowl and list of balloons launched there since the 50's StratoCat - Historical recopilation project on the use of stratospheric balloons in the scientific research, the military field and the aerospace activity