![Physicist Stephen Hawking in Zero Gravity NASA](https://upload.wikimedia.org/wikipedia/commons/0/08/Physicist_Stephen_Hawking_in_Zero_Gravity_NASA.jpg)
A reduced-gravity aircraft is a type of
fixed-wing aircraft
A fixed-wing aircraft is a heavier-than-air flying machine, such as an airplane, which is capable of flight using wings that generate lift caused by the aircraft's forward airspeed and the shape of the wings. Fixed-wing aircraft are distinc ...
that provides brief near-weightless environments for training
astronaut
An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a human spaceflight program to serve as a commander or crew member aboard a spacecraft. Although generally r ...
s, conducting research and making gravity-free movie shots.
Versions of such airplanes were operated by the
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
Reduced Gravity Research Program, and one is currently operated by the Human Spaceflight and Robotic Exploration Programmes of the European Space Agency. The unofficial nickname "vomit comet" became popular among those who experienced their operation.
History
Parabolic flight as a way of simulating weightlessness was first proposed by the German aerospace engineer Fritz Haber and the German physicist
Heinz Haber
Heinz Haber (May 15, 1913 in Mannheim – February 13, 1990 in Hamburg) was a German physicist and science writer who primarily became known for his TV programs and books about physics and environmental subjects. His lucid style of explaining ...
in 1950. Both had been brought to the US after
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
as part of
Operation Paperclip
Operation Paperclip was a secret United States intelligence program in which more than 1,600 German scientists, engineers, and technicians were taken from the former Nazi Germany to the U.S. for government employment after the end of World Wa ...
. As well,
Shih-Chun Wang
Shih-Chun Wang (1910-1993) was a Chinese-Americans, Chinese-American medical doctor, neuroscientist, and pharmacology professor.
Early life and education
Wang was born on January 25, 1910, in Tientsin, China. He attended Yenching University in B ...
studied nausea in astronauts for
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research.
NASA was established in 1958, succeeding t ...
, which helped lead to the creation of the vomit comet.
Parabolic flights are sometimes used to examine the effects of weightlessness on a living organism. While humans are by far the most common passengers, non-human animals have occasionally been involved in experiments, including a notable experiment on how weightlessness affected a
domestic cat
The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members o ...
's
righting reflex The righting reflex, also known as the labyrinthine righting reflex, is a reflex that corrects the orientation of the body when it is taken out of its normal upright position. It is initiated by the vestibular system, which detects that the body is ...
and a
pigeon
Columbidae () is a bird family consisting of doves and pigeons. It is the only family in the order Columbiformes. These are stout-bodied birds with short necks and short slender bills that in some species feature fleshy ceres. They primarily ...
's attempts to navigate in a weightless state.
Operating principles
The aircraft gives its occupants the sensation of weightlessness by following a
parabolic flight path relative to the center of the Earth. While following this path, the aircraft and its payload are in
free fall
In Newtonian physics, free fall is any motion of a body where gravity is the only force acting upon it. In the context of general relativity, where gravitation is reduced to a space-time curvature, a body in free fall has no force acting on ...
at certain points of its flight path. The aircraft is used in this way to demonstrate to astronauts what it is like to
orbit
In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a p ...
the Earth. During this time the aircraft does not exert any
ground reaction force In physics, and in particular in biomechanics, the ground reaction force (GRF) is the force exerted by the ground on a body in contact with it.
For example, a person standing motionless on the ground exerts a contact force on it (equal to the person ...
on its contents, causing the sensation of weightlessness.
Initially, the aircraft climbs with a pitch angle of 45 degrees using engine thrust and elevator controls. The sensation of weightlessness is achieved by reducing thrust and lowering the nose to maintain a neutral, or "zero lift", configuration such that the aircraft follows a ballistic trajectory, with engine thrust exactly compensating for drag. Weightlessness begins while ascending and lasts all the way "up-and-over the hump", until the craft reaches a downward pitch angle of around 30 degrees. At this point, the craft is pointing downward at high speed and must begin to pull back into the nose-up attitude to repeat the maneuver. The forces are then roughly twice that of gravity on the way down, at the bottom, and up again. This lasts all the way until the aircraft is again halfway up its upward trajectory, and the pilot again reduces the thrust and lowers the nose.
This aircraft is used to train astronauts in zero-g maneuvers, giving them about 25 seconds of weightlessness out of 65 seconds of flight in each
parabola
In mathematics, a parabola is a plane curve which is mirror-symmetrical and is approximately U-shaped. It fits several superficially different mathematical descriptions, which can all be proved to define exactly the same curves.
One descript ...
. During such training, the airplane typically flies about 40–60 parabolic maneuvers. In about two thirds of the passengers, these flights produce
nausea
Nausea is a diffuse sensation of unease and discomfort, sometimes perceived as an urge to vomit. While not painful, it can be a debilitating symptom if prolonged and has been described as placing discomfort on the chest, abdomen, or back of the ...
due to
airsickness
Airsickness is a specific form of motion sickness which is induced by air travel and is considered a normal response in healthy individuals. Airsickness occurs when the central nervous system receives conflicting messages from the body (including ...
,
giving the plane its nickname "vomit comet".
Operators
Canada
The
Canadian Space Agency and the
National Research Council National Research Council may refer to:
* National Research Council (Canada), sponsoring research and development
* National Research Council (Italy), scientific and technological research, Rome
* National Research Council (United States), part of ...
have a
Falcon 20
The Dassault Falcon 20 is a French business jet developed and manufactured by Dassault Aviation. The first business jet developed by the firm, it became the first of a family of business jets to be produced under the same name; of these, both ...
used for microgravity research. The small plane is normally not used for people to float freely and experience weightlessness; however, comedian
Rick Mercer
Richard Vincent "Rick" Mercer (born October 17, 1969) is a Canadian comedian, television personality, political satirist, and author. He is best known for his work on the CBC Television comedy shows ''This Hour Has 22 Minutes'' and '' Rick Merc ...
did so for a segment of his
show.
Ecuador
The first zero G plane to enter service in Latin America is a
T-39 Sabreliner
The North American Sabreliner, later sold as the Rockwell Sabreliner, is an American mid-sized business jet developed by North American Aviation. It was offered to the United States Air Force (USAF) in response to its Utility Trainer Experimen ...
nicknamed ''CONDOR'', operated for the
Ecuadorian Civilian Space Agency
The Ecuadorian Civilian Space Agency (EXA; es, Agencia Espacial Civil Ecuatoriana) is a private Ecuadorian organization founded in 2007 that conducts research on space and planetary sciences. It is a non-profit non-governmental organization with ...
and the
Ecuadorian Air Force
The Ecuadorian Air Force ( es, Fuerza Aérea Ecuatoriana, FAE) is the Air arm of the Military of Ecuador and responsible for the protection of the Ecuadorian airspace.
Mission
To develop the military air wing, in order to execute institutional ...
since May 2008.
On June 19, 2008, this plane carried a seven-year-old boy, setting the Guinness world record for the youngest person to fly in microgravity.
Europe
Since 1984,
ESA
, owners =
, headquarters = Paris, Île-de-France, France
, coordinates =
, spaceport = Guiana Space Centre
, seal = File:ESA emblem seal.png
, seal_size = 130px
, image = Views in the Main Control Room (120 ...
and the
CNES
The (CNES; French: ''Centre national d'études spatiales'') is the French government space agency (administratively, a "public administration with industrial and commercial purpose"). Its headquarters are located in central Paris and it is und ...
have flown reduced-gravity missions in a variety of aircraft, including NASA's KC-135, a
Caravelle, an
Ilyushin IL-76 MDK and an
Airbus A300
The Airbus A300 is a wide-body airliner developed and manufactured by Airbus.
In September 1967, aircraft manufacturers in the United Kingdom, France, and West Germany signed a memorandum of understanding to develop a large airliner.
West ...
known as the '. In 2014 the A300 was phased out in favor of a more modern
Airbus A310
The Airbus A310 is a wide-body aircraft, designed and manufactured by Airbus Industrie, then a consortium of European aerospace manufacturers.
Airbus had identified a demand for an aircraft smaller than the A300, the first twin-jet wide-bod ...
, also named ''Zero-G''. It is based at
Bordeaux-Mérignac airport in
France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of Overseas France, overseas regions and territories in the Americas and the Atlantic Ocean, Atlantic, Pacific Ocean, Pac ...
, operated by Novespace, and has also been flown from
Paris Le Bourget airport
Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. Si ...
and
Dübendorf Air Base
Dübendorf Military Airport (german: Militärflugplatz Dübendorf) was a military airfield of the Swiss Air Force northeast of Dübendorf in Switzerland, located east of Zürich.
History
The search for a suitable site for an airfield started ...
in Switzerland. Since 1997 CNES subsidiary Novespace has handled the management of these flights.
This aircraft is used also to realize commercial flights for public passengers in partnership between operator Novespace and the
Avico company, under Air Zero G brand. The aircraft has also been used for cinema purposes, with
Tom Cruise
Thomas Cruise Mapother IV (born July 3, 1962), known professionally as Tom Cruise, is an American actor and producer. One of the world's highest-paid actors, he has received various accolades, including an Honorary Palme d'Or and three Gol ...
and
Annabelle Wallis filming for ''
The Mummy
A mummy is an unusually well preserved corpse.
Mummy or The Mummy may also refer to:
Places
*Mummy Range, a mountain range in the Rocky Mountains of northern Colorado in the United States
*Mummy Cave, a rock shelter and archeological site in Par ...
'' in 2017.
Russia
In Russia, commercial flights are offered on the
Ilyushin Il-76
The Ilyushin Il-76 (russian: Илью́шин Ил-76; NATO reporting name: Candid) is a multi-purpose, fixed-wing, four-engine turbofan strategic airlifter designed by the Soviet Union's Ilyushin design bureau. It was first planned as a comm ...
jet; several U.S. companies book flights on these jets.
United States
NASA
NASA flew zero gravity flights on various aircraft for many years. In 1959
Project Mercury
Project Mercury was the first human spaceflight program of the United States, running from 1958 through 1963. An early highlight of the Space Race, its goal was to put a man into Earth orbit and return him safely, ideally before the Soviet Un ...
astronauts trained in a
C-131 Samaritan
The Convair C-131 Samaritan is an American twin-engined military transport produced from 1954 to 1956 by Convair. It is the military version of the Convair CV-240 family of airliners.Gradidge 1997, p. 20–21.
Design and development
The design ...
aircraft dubbed the "vomit comet".
[. Page hosts a NASA photograph dated 01/01/1959.]
Twin
KC-135 Stratotanker
The Boeing KC-135 Stratotanker is an American military aerial refueling aircraft that was developed from the Boeing 367-80 prototype, alongside the Boeing 707 airliner. It is the predominant variant of the C-135 Stratolifter family of transpo ...
s were used until December 2004 and later retired. One, a KC-135A registered N930NA (also known as NASA 930, formerly USAF serial no. 59-1481), flew more than 58,000 parabolas after NASA acquired it in 1973, before being retired in 1995. It is now on display at
Ellington Field
Ellington Field Joint Reserve Base is a joint installation shared by various active component and reserve component military units, as well as aircraft flight operations of the National Aeronautics and Space Administration (NASA) under the aegis ...
, near the
Johnson Space Center
The Lyndon B. Johnson Space Center (JSC) is NASA's center for human spaceflight (originally named the Manned Spacecraft Center), where human spaceflight training, research, and flight control are conducted. It was renamed in honor of the late U ...
. The other (N931NA or NASA 931, formerly AF serial no. 63-7998) was also used by
Universal Pictures
Universal Pictures (legally Universal City Studios LLC, also known as Universal Studios, or simply Universal; common metonym: Uni, and formerly named Universal Film Manufacturing Company and Universal-International Pictures Inc.) is an Ameri ...
and
Imagine Entertainment
Imagine Entertainment (formerly Imagine Films Entertainment), also known simply as Imagine, is an American film and television production company founded in November 1985 by producer Brian Grazer and director Ron Howard.
Background
Brian Graz ...
for filming scenes involving weightlessness in the movie ''
Apollo 13
Apollo 13 (April 1117, 1970) was the seventh crewed mission in the Apollo space program and the third meant to land on the Moon. The craft was launched from Kennedy Space Center on April 11, 1970, but the lunar landing was aborted aft ...
''; it made its final flight on October 29, 2004, and is permanently stored in the
Pima Air & Space Museum
The Pima Air & Space Museum, located in Tucson, Arizona, is one of the world's largest non-government funded aerospace museums. The museum features a display of nearly 300 aircraft spread out over 80 acres (320,000 m²) on a campus oc ...
in Tucson, Arizona.
In 2005 NASA replaced the aircraft with a
McDonnell Douglas
McDonnell Douglas was a major American aerospace manufacturing corporation and defense contractor, formed by the merger of McDonnell Aircraft and the Douglas Aircraft Company in 1967. Between then and its own merger with Boeing in 1997, it produ ...
C-9B Skytrain II (N932NA) formerly owned by
KLM Royal Dutch Airlines and the
United States Navy
The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...
.
NASA concluded the Reduced Gravity Research Program and ended operations in July 2014, due to aircraft technical problems. It is replaced with private company contracts.
NASA had a microgravity services contract with
Zero Gravity Corporation
Zero Gravity Corporation (also known as Zero-G, stylized as ''zero G'') is an American company based in Exploration Park, Florida, formerly of Fort Lauderdale, Florida, which operates weightless flights from United States airports. Unlike NASA ...
(ZERO-G) and used its aircraft, G-FORCE ONE, a modified Boeing
727-200.
Other operators
In late 2004, the
Zero Gravity Corporation
Zero Gravity Corporation (also known as Zero-G, stylized as ''zero G'') is an American company based in Exploration Park, Florida, formerly of Fort Lauderdale, Florida, which operates weightless flights from United States airports. Unlike NASA ...
became the first company in the United States to offer zero-g flights to the general public, using
Boeing 727
The Boeing 727 is an American narrow-body airliner that was developed and produced by Boeing Commercial Airplanes.
After the heavy 707 quad-jet was introduced in 1958, Boeing addressed the demand for shorter flight lengths from smaller airpo ...
jets. Each flight consists of around 15 parabolas, including simulations of the gravity levels of the Moon and Mars, as well as complete weightlessness. This profile allows ZERO-G's clients to enjoy weightlessness with minimal motion discomfort.
In 2015,
Integrated Spaceflight Services, began serving as the research and education integrator of the
National Research Council of Canada
The National Research Council Canada (NRC; french: Conseil national de recherches Canada) is the primary national agency of the Government of Canada dedicated to science and technology research & development. It is the largest federal research ...
for the US market, offering comprehensive reduced-gravity services on a modified
Falcon 20
The Dassault Falcon 20 is a French business jet developed and manufactured by Dassault Aviation. The first business jet developed by the firm, it became the first of a family of business jets to be produced under the same name; of these, both ...
aircraft. ISS has flown annual microgravity research campaigns to evaluate space suits and other technologies with
Project PoSSUM
A project is any undertaking, carried out individually or collaboratively and possibly involving research or design, that is carefully planned to achieve a particular goal.
An alternative view sees a project managerially as a sequence of even ...
.
Aurora Aerospace
An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of br ...
in
Oldsmar, Florida
Oldsmar is a city in Pinellas County, Florida, United States. As of the 2010 census, the city had a population of 13,591. The Oldsmar name dates to April 12, 1916 when automobile pioneer Ransom E. Olds purchased of land by the northern part of Ta ...
offers zero-g flights using a
Fuji/Rockwell Commander 700. It is also used to simulate the gravity of the Moon and Mars.
Airsickness
According to former Reduced Gravity Research Program director John Yaniec, anxiety contributes most to passengers' airsickness. The stress on their bodies creates a sense of panic and therefore causes the passenger to vomit. Yaniec gives a rough estimate of passengers, that "one third
ecome/nowiki> violently ill, the next third moderately ill, and the final third not at all." Vomiting is referred to as "ill".
Scopolamine is often used as an antiemetic
An antiemetic is a drug that is effective against vomiting and nausea. Antiemetics are typically used to treat motion sickness and the side effects of opioid analgesics, general anaesthetics, and chemotherapy directed against cancer. They may ...
during reduced-gravity-aircraft training.
Use in media production
In 2016, rock group OK Go recorded a music video for their single Upside Down & Inside Out on a reduced-gravity aircraft, which involved acrobatic choreography created specifically for the zero-gravity environment.
The adult entertainment production company Private Media Group
Private Media Group, Inc. is a Swedish
Swedish or ' may refer to:
Anything from or related to Sweden, a country in Northern Europe. Or, specifically:
* Swedish language, a North Germanic language spoken primarily in Sweden and Finland
** Swedi ...
has filmed a pornographic
Pornography (often shortened to porn or porno) is the portrayal of sexual subject matter for the exclusive purpose of sexual arousal. Primarily intended for adults, movie called ''The Uranus Experiment: Part Two'' where a zero-gravity intercourse scene was filmed aboard a reduced-gravity aircraft. The filming process was particularly difficult from a technical and logistical standpoint. Budget constraints allowed for only one shot, featuring the actors Sylvia Saint and Nick Lang. Berth Milton, Jr
Berth or berthing may refer to:
Transport
* Berthing, a cabin on a ship or train
* Berthing (spacecraft), the placement of a spacecraft into a berthing mechanism through the use of a robotic arm
* Berth (moorings)
* Berth (sleeping)
Other ...
, president and CEO
A chief executive officer (CEO), also known as a central executive officer (CEO), chief administrator officer (CAO) or just chief executive (CE), is one of a number of corporate executives charged with the management of an organization especially ...
of Private Media Group, says "You would not want to be afraid of flying, that's for sure!"
See also
* Micro-g environment
The term micro-g environment (also μg, often referred to by the term microgravity) is more or less synonymous with the terms ''weightlessness'' and ''zero-g'', but emphasising that g-forces are never exactly zero—just very small (on the I ...
* Space tourism
Space tourism is human space travel for recreational purposes. There are several different types of space tourism, including orbital, suborbital and lunar space tourism.
During the period from 2001 to 2009, seven space tourists made eight s ...
* Astronaut training
Astronaut training describes the complex process of preparing astronauts in regions around the world for their space missions before, during and after the flight, which includes medical tests, physical training, extra-vehicular activity (EVA) tra ...
* Fallturm Bremen
Fallturm Bremen is a drop tower at the Center of Applied Space Technology and Microgravity at the University of Bremen in Bremen. It was built between 1988 and 1990, and includes a 122-metre-high drop tube (actual drop distance is 110 m), in whic ...
References
Further reading
* Haber, Fritz and Haber, Heinz: "Possible Methods of Producing the Gravity-Free State for Medical Research", ''Journal of Aviation Medicine'' XXI (1950).
* Karmali, Faisal and Shelhamer, Mark
"The dynamics of parabolic flight: flight characteristics and passenger percepts"
Acta Astronautica (2008).
* Easton, Pam (October 30, 2004)
NASA's weightless aircraft is retired
Associated Press.
* Golightly, Glen (May 15, 2000)
Space.com Houston Bureau.
* Overbye, Dennis (March 1, 2007), "Stephen Hawkin
to the ride of his life", ''New York Times''.
External links
{{commons category, Reduced gravity aircraft
Flight Opportunities program
* ttps://web.archive.org/web/20060619203013/http://microgravity.grc.nasa.gov/ground/aircraft.htm About the NASA Reduced Gravity Research Program
Vegitel ltd is a Russian company that offers zero-gravity flights in an IL-76 MDK wide-body aircraft
Virtual tour of the Airbus A-300 Zero-G
+
Space science
Weightlessness
Aircraft related to spaceflight