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Atmospheric satellite (United States usage, abbreviated atmosat) or pseudo-satellite (British usage) is a marketing term for an
aircraft
An aircraft is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engine ...
that operates in the atmosphere at high altitudes for extended periods of time, in order to provide services conventionally provided by an
artificial satellite
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisoto ...
orbiting in space.
Atmospheric satellites remain aloft through atmospheric lift, either
aerostatic/buoyancy (e.g.,
balloons) or
aerodynamic
Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dyn ...
(e.g.,
airplane
An airplane or aeroplane (informally plane) is a fixed-wing aircraft that is propelled forward by thrust from a jet engine, Propeller (aircraft), propeller, or rocket engine. Airplanes come in a variety of sizes, shapes, and wing configurat ...
s). By contrast, conventional satellites in
Earth orbit
Earth orbits the Sun at an average distance of 149.60 million km (92.96 million mi) in a counterclockwise direction as viewed from above the Northern Hemisphere. One complete orbit takes days (1 sidereal year), during which time Eart ...
operate in the vacuum of space and remain in flight through
centrifugal force
In Newtonian mechanics, the centrifugal force is an inertial force (also called a "fictitious" or "pseudo" force) that appears to act on all objects when viewed in a rotating frame of reference. It is directed away from an axis which is parall ...
derived from their orbital speed.
To date, all atmosats have been
unmanned aerial vehicle
An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without any human pilot, crew, or passengers on board. UAVs are a component of an unmanned aircraft system (UAS), which includes adding a ground-based controll ...
s (UAVs).
Design principles
An atmosat remains aloft through atmospheric lift, in contrast to a satellite in
Earth orbit
Earth orbits the Sun at an average distance of 149.60 million km (92.96 million mi) in a counterclockwise direction as viewed from above the Northern Hemisphere. One complete orbit takes days (1 sidereal year), during which time Eart ...
which moves freely at high speed in the vacuum of space, and orbits due to its centrifugal force matching the force of gravity. Satellites are expensive to build and launch, and any changes to their orbit requires expending their extremely limited fuel supply. Atmospheric satellites fly very slowly. They are intended to provide their various services more economically and with more versatility than current
low Earth orbit
A low Earth orbit (LEO) is an orbit around Earth with a period of 128 minutes or less (making at least 11.25 orbits per day) and an eccentricity less than 0.25. Most of the artificial objects in outer space are in LEO, with an altitude never mor ...
satellites.
[
Operating altitudes are expected to be in the ]tropopause
The tropopause is the atmospheric boundary that demarcates the troposphere from the stratosphere; which are two of the five layers of the atmosphere of Earth. The tropopause is a thermodynamic gradient-stratification layer, that marks the end of ...
—at approximately 65,000 feet—where winds are generally less than 5 knots and clouds do not block sunlight. It is desirable in the United States to operate above 60,000 feet, above which the Federal Aviation Administration does not regulate the airspace.[
There are two classes of atmosat, respectively gaining their lift through either aerostatic (e.g., balloons) or ]aerodynamic
Aerodynamics, from grc, ἀήρ ''aero'' (air) + grc, δυναμική (dynamics), is the study of the motion of air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dyn ...
(e.g., airplane
An airplane or aeroplane (informally plane) is a fixed-wing aircraft that is propelled forward by thrust from a jet engine, Propeller (aircraft), propeller, or rocket engine. Airplanes come in a variety of sizes, shapes, and wing configurat ...
s) forces. In order to remain aloft for long periods, the NASA and Titan Aerospace designs use propeller-driven electric airplane
An electric aircraft is an aircraft powered by electricity.
Electric aircraft are seen as a way to reduce the environmental effects of aviation, providing zero emissions and quieter flights.
Electricity may be supplied by a variety of methods ...
s powered by solar cell
A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon. s, in contrast to Google
Google LLC () is an American Multinational corporation, multinational technology company focusing on Search Engine, search engine technology, online advertising, cloud computing, software, computer software, quantum computing, e-commerce, ar ...
's Project Loon
Loon LLC was an Alphabet Inc. subsidiary working on providing Internet access to rural and remote areas. The company used high-altitude balloons in the stratosphere at an altitude of to to create an aerial wireless network with up to 1 Mbi ...
which envisions using helium-filled high-altitude balloon
High-altitude balloons are crewed or uncrewed balloons, usually filled with helium or hydrogen, that are released into the stratosphere, generally attaining between above sea level. In 2002, a balloon named BU60-1 reached a record altitude of .
...
s.[
]
Airplanes
To enable night time operation and ensure endurance through consecutive 24-hour day/night cycles, in daylight hours solar panels charge batteries[ or fuel cells][ which subsequently power the vehicle during hours of darkness. An atmospheric satellite may initially ascend at night under battery power, and reach altitude soon after dawn to allow solar panels to take advantage of a full day's sunlight.]
Facebook
Facebook is an online social media and social networking service owned by American company Meta Platforms. Founded in 2004 by Mark Zuckerberg with fellow Harvard College students and roommates Eduardo Saverin, Andrew McCollum, Dustin Mosk ...
's UAV-based Aquila system expects to use laser communication
Free-space optical communication (FSO) is an optical communication technology that uses light propagating in free space to wirelessly transmit data for telecommunications or computer networking. "Free space" means air, outer space, vacuum, or ...
technology to provide Internet communication among UAVs, and also between UAVs and ground stations that in turn will connect to rural areas.[ The Aquila UAV is a carbon fiber, solar-powered flying wing design about the size of a passenger jet.][ ●
] Aquila's first test flight took place on June 28, 2016. It flew for ninety minutes, reaching a maximum altitude of 2150 feet, and was substantially damaged when a twenty-foot section of the righthand wing broke off during final approach to landing. The Aquila is designed and manufactured by the UK company Ascenta.
Luminati Aerospace
Hola is a freemium web and mobile application which provides a form of VPN service to its users through a peer-to-peer network. It also uses peer-to-peer caching. When a user accesses certain domains that are known to use geo-blocking, the Hola ...
claims its Substrata solar-powered aircraft could remain aloft indefinitely up to a latitude of 50° through formation flight
Formation flying is the flight of multiple objects in coordination.
Introduction
Formation flight in aviation originated in World War I when fighter aircraft were assigned to escort reconnaissance aircraft. It was found that pairs of aircraft w ...
like migratory geese
A goose ( : geese) is a bird of any of several waterfowl species in the family Anatidae. This group comprises the genera '' Anser'' (the grey geese and white geese) and ''Branta'' (the black geese). Some other birds, mostly related to the she ...
, reducing by 79% the power required for the trailing aircraft and allowing smaller airframes.
Balloons
A geostationary balloon satellite (GBS) flies in the stratosphere ( above sea level) at a fixed point over the Earth's surface. At that altitude the air has 1/10 of its density
Density (volumetric mass density or specific mass) is the substance's mass per unit of volume. The symbol most often used for density is ''ρ'' (the lower case Greek letter rho), although the Latin letter ''D'' can also be used. Mathematical ...
is at sea level
Mean sea level (MSL, often shortened to sea level) is an average surface level of one or more among Earth's coastal bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical datuma standardise ...
. The average wind speed at these altitudes is less than that at the surface.
A GBS could be used to provide broadband Internet access over a large area.
One prior project was the Google
Google LLC () is an American Multinational corporation, multinational technology company focusing on Search Engine, search engine technology, online advertising, cloud computing, software, computer software, quantum computing, e-commerce, ar ...
's Project Loon
Loon LLC was an Alphabet Inc. subsidiary working on providing Internet access to rural and remote areas. The company used high-altitude balloons in the stratosphere at an altitude of to to create an aerial wireless network with up to 1 Mbi ...
, which envisioned using helium-filled high-altitude balloon
High-altitude balloons are crewed or uncrewed balloons, usually filled with helium or hydrogen, that are released into the stratosphere, generally attaining between above sea level. In 2002, a balloon named BU60-1 reached a record altitude of .
...
s.
Applications
Proposed applications for atmosats include border security, maritime traffic monitoring, anti-piracy operations, disaster response, agricultural observation, atmospheric observation, weather monitoring, communications relay, oceanographic research, Earth imaging and telecommunications.[ Facebook is reportedly envisioning providing Internet access to the African continent with a fleet of 11,000 vehicles.][
]
High-altitude long endurance
High-altitude long endurance (HALE) is the description of an air-borne vehicle which functions optimally at high-altitude (as high as 60,000 feet) and is capable of flights which last for considerable periods of time without recourse to landing. The tropopause
The tropopause is the atmospheric boundary that demarcates the troposphere from the stratosphere; which are two of the five layers of the atmosphere of Earth. The tropopause is a thermodynamic gradient-stratification layer, that marks the end of ...
represents high-altitude.
Craft
Lockheed-Martin
The Lockheed Martin Corporation is an American aerospace, arms, defense, information security, and technology corporation with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It is ...
have produced a HALE Demonstrator, which was the first of this type of craft. The HALE-D vehicle was launched during July the 27th 2011 to operate from a location which is higher than the jet-stream in a geostationary position. The HALE-D was to function as a surveillance platform, telecommunications
Telecommunication is the transmission of information by various types of technologies over wire, radio, optical, or other electromagnetic systems. It has its origin in the desire of humans for communication over a distance greater than that fe ...
relay, or a weather observer.
The Northrop Grumman
Northrop Grumman Corporation is an American multinational aerospace and defense technology company. With 90,000 employees and an annual revenue in excess of $30 billion, it is one of the world's largest weapons manufacturers and military techn ...
RQ-4 Global Hawk
The Northrop Grumman RQ-4 Global Hawk is a high-altitude, remotely-piloted surveillance aircraft of the 1990s–2020s. It was initially designed by Ryan Aeronautical (now part of Northrop Grumman), and known as Tier II+ during development. The ...
is an example of a HALE UAV. A total 42 of them have been in service with the United States Air Force
The United States Air Force (USAF) is the Aerial warfare, air military branch, service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part ...
, beginning in 1998. It carries high-fidelity radar
Radar is a detection system that uses radio waves to determine the distance ('' ranging''), angle, and radial velocity of objects relative to the site. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, we ...
, electro-optical
Electro–optics is a branch of electrical engineering, electronic engineering, materials science, and material physics involving components, electronic devices such as lasers, laser diodes, LEDs, waveguides, etc. which operate by the propag ...
, and infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
sensors, enabling it to surveil as much as 40,000 square miles (100,000 km2) of terrain a day.
Bayraktar's Akıncı was produced as a HALE class UAV and is set to go into service in 2021 or late 2020.
Proteus high-altitude aircraft operates at altitudes of 19.8 km (65,000 ft), while carrying a 1,100 kg weight, with an endurance time of 18 hours maximum.
Altus II, (Latin
Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
: ''Altus
Altus or ALTUS may refer to:
Music
* Alto, a musical term meaning second highest musical or vocal type
*Altus (voice type), a vocal type also known as countertenor
Places
* Altus, Arkansas, US
**Altus AVA, a wine-growing region near Altus, Arka ...
'' meaning ''high'') runs at altitudes of 18.3 km (60,000 ft), with endurance times of 24 hours approximately, with variations of capabilities of endurance dependent on the altitude of operation.
Boeing Phantom Eye
The Boeing Phantom Eye was a High-Altitude Long Endurance, high altitude, long endurance (HALE) liquid hydrogen-powered unmanned aerial vehicle developed by Boeing Phantom Works. The aircraft was Boeing's proposal to meet the demand from the US ...
is able to maintain flight at altitude for four days with a payload; a design variant is able to maintain flight at altitude for ten days, while carrying a payload.
A design paper (Z. Goraj ''et al'' 2004) describes the HALE PW-114 craft, equipped with sensors to fly at a height of 20 kilometres for a duration of 40 hours.
RQ-3A DarkStar is a high-stealth oriented craft built to function optimally within highly defended areas, in order to do reconnaissance. The craft is intended to hover over targets for at least eight hours, at heights of 13.7 km (45,000 ft) and beyond.
The Airbus Zephyr
The Airbus Zephyr is a series of lightweight solar-powered unmanned aerial vehicles (UAV). The latest model is a high-altitude platform station capable of flying at for months at a time without fueling. It has a wingspan of and weighs .
Deve ...
was designed to fly at a maximum height of altitude 21.3 km (70 000 ft), and in a 2006 flight, it was airborne for 80 hours, which was then was the longest flight made by a HALE vehicle. Model 7 holds the official long-endurance record for an UAV of 336 hours, 22 minutes and 8 seconds, a flight made from the 9th to the 23rd of July 2010.
A160 Hummingbird
The Boeing A160 Hummingbird (military designation: YMQ-18A) is an unmanned aerial vehicle (UAV) helicopter. Its design incorporates many new technologies never before used in helicopters, allowing for greater endurance and altitude than any helic ...
is a rotorcraft produced by Boeing.
Guizhou Soar Dragon, produced by Chengdu Aircraft Industry Group
The Chengdu Aircraft Industry Group (CAIG) or Chengdu Aerospace Corporation (CAC), a subsidiary of AVIC, is a Chinese aerospace conglomerate that designs and manufactures combat aircraft and is also a manufacturer of aircraft parts. It was foun ...
, is a HALE UAV used for military reconnaissance, with a service ceiling of 18 km and range of 7,000 km.
The Divine Eagle, produced by Shenyang Aircraft Corporation
Shenyang Aircraft Corporation (SAC) or Shenyang Aerospace Corporation is a Chinese civilian and military aircraft manufacturer located in Shenyang, Liaoning, a subsidiary of the state-owned aircraft manufacturer AVIC. Founded in 1951 as the cl ...
, is a large HALE UAV with an extremely large wingspan, and designed for cruising at very high altitude. It is a twin-boom aircraft
A twin-boom aircraft is characterised by two longitudinal booms (extended nacelle-like bodies). The booms may contain ancillary items such as fuel tanks and/or provide a supporting structure for other items. Typically, twin tailbooms support ...
. It is speculated to carry a series of airborne early warning radars of the active electronically scanned array type, and notably with some anti-stealth capability. During its development, it was designated an "anti stealth UAV". It is one of a series of SYAC UAV.
Swift Engineering
Swift Engineering Inc. is an American spacecraft engineering firm that builds autonomous systems, helicopters, submarines, spacecraft, ground vehicles, robotics, and composite parts. Swift used to produce racing cars for open-wheel racing series ...
's Swift Ultra Long Endurance SULE Sule may refer to:
* Sule (river), a river of Lower Saxony, Germany
* Sule Skerry, a skerry in the North Atlantic off the north coast of Scotland
* Sule Stack, a stack in the North Atlantic off the north coast of Scotland
* Punta Sulè, a mountai ...
completed its maiden flight partnership with NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...
's Ames Research Center in July 2020.
High-altitude platform station
High-altitude platform station or high-altitude pseudo-satellite (short: HAPS) or high-altitude platform (short: HAP or HAPs lural is – according to ''Article 1.66A'' of the International Telecommunication Union's (ITU) ITU Radio Regulations
The ITU Radio Regulations (short: RR) is a basic document of the International Telecommunication Union (ITU) that regulates on law of nations scale radiocommunication services and the utilisation of radio frequencies. It is the supplementation t ...
(RR) – defined as "a station on an object at an altitude of 20 to 50 km and at a specified, nominal, fixed point relative to the Earth".
Each ''station'' shall be classified by the ''service'' in which it operates permanently or temporarily.
;See also:
Design considerations
Limitation due to power
A HAP can be a manned or unmanned airplane
An airplane or aeroplane (informally plane) is a fixed-wing aircraft that is propelled forward by thrust from a jet engine, Propeller (aircraft), propeller, or rocket engine. Airplanes come in a variety of sizes, shapes, and wing configurat ...
, a balloon
A balloon is a flexible bag that can be inflated with a gas, such as helium, hydrogen, nitrous oxide, oxygen, and air. For special tasks, balloons can be filled with smoke, liquid water, granular media (e.g. sand, flour or rice), or light so ...
, or an airship
An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from a lifting gas that is less dense than the surrounding air.
In early ...
. All require electrical power to keep themselves and their payload functional. While current HAPS are powered by batteries or engines, mission time is limited by the need for recharging/refueling. Therefore, alternative means are being considered for the future. Solar cell
A solar cell, or photovoltaic cell, is an electronic device that converts the energy of light directly into electricity by the photovoltaic effect, which is a physical and chemical phenomenon. s are one of the best options currently being used under trial for HAPS ( Helios, Lindstrand HALE).
Altitude selection for HAPS
Whether an airship or an aeroplane, a major challenge is the ability of the HAP to maintain stationkeeping in the face of winds. An operating altitude between 17 and 22 km is chosen because in most regions of the world this represents a layer of relatively mild wind and turbulence
In fluid dynamics, turbulence or turbulent flow is fluid motion characterized by chaotic changes in pressure and flow velocity. It is in contrast to a laminar flow, which occurs when a fluid flows in parallel layers, with no disruption between ...
above the jet stream. Although the wind profile may vary considerably with latitude and with season, a form similar to that shown will usually obtain. This altitude (> 17 km) is also above commercial air-traffic heights, which would otherwise prove a potentially prohibitive constraint.
Comparison to satellites
Since HAPS operate at much lower altitudes than satellites, it is possible to cover a small region much more effectively. Lower altitude also means much lower telecommunications link budget
A link budget is an accounting of all of the power gains and losses that a communication signal experiences in a telecommunication system; from a transmitter, through a communication medium such as radio waves, cable, waveguide, or optical fibe ...
(hence lower power consumption) and smaller round-trip delay compared to satellites. Furthermore, deploying a satellite requires significant time and monetary resources, in terms of development and launch. HAPS, on the other hand, are comparatively less expensive and are rapidly deployable. Another major difference is that a satellite, once launched, cannot be landed for maintenance, while HAPS can.
Applications
Telecommunications
One of the latest uses of HAPS has been for radiocommunication service
Radio communication service or radiocommunication service is according to Article 1.19 of the International Telecommunication Union's Radio Regulations (ITU RR),ITU Radio Regulations, Section III – Radio services, Article 1.19, definition: Ra ...
. Research on HAPS is being actively carried largely in Europe, where scientists are considering them as a platform to deliver high-speed connectivity to users, over . It has gained significant interest because HAPS will be able to deliver bandwidth and capacity similar to a broadband
In telecommunications, broadband is wide bandwidth data transmission which transports multiple signals at a wide range of frequencies and Internet traffic types, that enables messages to be sent simultaneously, used in fast internet connections. ...
wireless access network (such as WiMAX
Worldwide Interoperability for Microwave Access (WiMAX) is a family of wireless broadband communication standards based on the IEEE 802.16 set of standards, which provide physical layer (PHY) and media access control (MAC) options.
The WiMAX ...
) while providing a coverage area similar to that of a satellite.
High-altitude airships can improve the military's ability to communicate in remote areas such as those in Afghanistan, where mountainous terrain frequently interferes with communications signals.
Surveillance and intelligence
One of the best examples of a high-altitude platform used for surveillance and security is Northrop Grumman RQ-4 Global Hawk
The Northrop Grumman RQ-4 Global Hawk is a high-altitude, remotely-piloted surveillance aircraft of the 1990s–2020s. It was initially designed by Ryan Aeronautical (now part of Northrop Grumman), and known as Tier II+ during development. The ...
UAV used by the US Air Force
The United States Air Force (USAF) is the air service branch of the United States Armed Forces, and is one of the eight uniformed services of the United States. Originally created on 1 August 1907, as a part of the United States Army Sig ...
. It has a service ceiling of 20 km and can stay in the air for continuous 36 hours. It carries a highly sophisticated sensor system including radar, optical, and infrared imagers. It is powered by a turbofan
The turbofan or fanjet is a type of airbreathing jet engine that is widely used in aircraft propulsion. The word "turbofan" is a portmanteau of "turbine" and "fan": the ''turbo'' portion refers to a gas turbine engine which achieves mechanic ...
engine and is able to deliver digital sensor data in realtime to a ground station.
Real-time monitoring of a region
Another future use that is currently being investigated is monitoring of a particular area or region for activities such as flood detection, seismic
Seismology (; from Ancient Greek σεισμός (''seismós'') meaning "earthquake" and -λογία (''-logía'') meaning "study of") is the scientific study of earthquakes and the propagation of elastic waves through the Earth or through other ...
monitoring, remote sensing
Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring information about Eart ...
and disaster management.
Weather and environmental monitoring
Perhaps the most common use of high-altitude platforms is for environment/weather monitoring. Numerous experiments are conducted through high-altitude balloons mounted with scientific equipment, which is used to measure environmental changes or to keep track of weather. Recently, NASA
The National Aeronautics and Space Administration (NASA ) is an independent agencies of the United States government, independent agency of the US federal government responsible for the civil List of government space agencies, space program ...
in partnership with The National Oceanic and Atmospheric Administration ( NOAA), has started using Global Hawk UAV to study Earth's atmosphere.
As a rocket launch platform
Due to the height, more than 90% of atmospheric matter is below the high-altitude platform. This reduces atmospheric drag for starting rockets.
"As a rough estimate, a rocket that reaches an altitude of 20 km when launched from the ground will reach 100 km if launched at an altitude of 20 km from a balloon."
Such a platform has been proposed to allow the usage of (long) mass driver
A mass driver or electromagnetic catapult is a proposed method of non-rocket spacelaunch which would use a linear motor to accelerate and catapult payloads up to high speeds. Existing and contemplated mass drivers use coils of wire energized by e ...
s for launching goods or humans into orbit.
Lockheed-Martin High-Altitude Airship (HAA)
The United States Department of Defense
The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national sec ...
Missile Defense Agency
The Missile Defense Agency (MDA) is the section of the United States government's Department of Defense responsible for developing a layered defense against ballistic missiles. It had its origins in the Strategic Defense Initiative (SDI) which w ...
contracted Lockheed Martin to construct a High-Altitude Airship (HAA) to enhance its Ballistic Missile Defense System (BMDS).
An unmanned lighter-than-air vehicle, the HAA was proposed to operate at a height of above in a quasi-geostationary position to deliver persistent orbital station keeping
In astrodynamics, orbital station-keeping is keeping a spacecraft at a fixed distance from another spacecraft or celestial body. It requires a series of orbital maneuvers made with thruster burns to keep the active craft in the same orbit as its ...
as a surveillance aircraft platform, telecommunications relay, or a weather observer. They originally proposed to launch their HAA in 2008. The airship would be in the air for up to one month at a time and was intended to survey a diameter of land. It was to use solar cells to provide its power and would be unmanned during its flight. The production concept would be long and in diameter. To minimize weight. it was to be composed of high strength fabrics and use lightweight propulsion technologies.
A subscale demonstrator unit for this project, the "High Altitude Long Endurance-Demonstrator" (HALE-D), was built by Lockheed Martin and launched on a test flight on July 27, 2011, to demonstrate key technologies critical to the development of unmanned airships. The airship was supposed to reach an altitude of , but a problem with the helium levels occurred at which prevented it from reaching its target altitude, and the flight was terminated. It descended and landed at a speed of about 20 feet per second[Jim Mackinnon]
"Lockheed Martin's prototype blimp crashes during maiden voyage"
'' Akron Beacon Journal'', July 27, 2011 (accessed 25 March 2016) in a heavily forested area in Pennsylvania. Two days after the landing, before the vehicle was recovered from the crash site, the vehicle was destroyed by fire.
Stratospheric airship
A stratospheric airship is a powered airship designed to fly at very high altitudes . Most designs are remote-operated aircraft/unmanned aerial vehicles (ROA/UAV
An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without any human pilot, crew, or passengers on board. UAVs are a component of an unmanned aircraft system (UAS), which includes adding a ground-based controlle ...
). To date none of these designs have received approval from the FAA
The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic m ...
to fly in U.S. airspace.
Stratospheric airship efforts are being developed in at least five countries.
The first stratospheric powered airship flight took place in 1969, reaching for 2 hours with a payload. On December 4, 2005, a team led by Southwest Research Institute (SwRI), sponsored by the Army Space and Missile Defense Command (ASMDC), successfully demonstrated powered flight of the HiSentinel stratospheric airship at an altitude of .
Japan
and South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia, constituting the southern part of the Korean Peninsula and sharing a land border with North Korea. Its western border is formed by the Yellow Sea, while its eas ...
are also planning to deploy HAAs. South Korea has been conducting flight tests for several years with a vehicle from Worldwide Aeros.
Aircraft
In January 2018, several systems were in development:
* AeroVironment will design and development solar-powered UAV prototypes for $65 million for HAPSMobile, a joint venture 95% funded and owned by Japanese telco SoftBank
is a Japanese multinational conglomerate holding company headquartered in Minato, Tokyo which focuses on investment management. The Group primarily invests in companies operating in technology, energy, and financial sectors. It also runs the Vi ...
; its -span Helios Prototype
The Helios Prototype was the fourth and final aircraft developed as part of an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Environmental Research A ...
first flew in 1999 and reached in 2001 before breaking up in flight in 2003; in 2002, its -span Pathfinder Plus carried a communications payload to FL650; its hydrogen-powered Global Observer
The AeroVironment Global Observer is a concept for a high-altitude, long endurance unmanned aerial vehicle, designed by AeroVironment (AV) to operate as a stratospheric geosynchronous satellite system with regional coverage.
Two Global Observer ...
designed to stay aloft a week in the stratosphere first flew in 2010 but crashed in 2011.
* Airbus
Airbus SE (; ; ; ) is a European multinational aerospace corporation. Airbus designs, manufactures and sells civil and military aerospace products worldwide and manufactures aircraft throughout the world. The company has three divisions: ' ...
builds the Zephyr, spanning and weighing less than , it is designed to stay aloft for months; a 2010 version flew for 14 days, while in July 2018, a Zephyr flew continuously for 25 days, 23 hours, and 57 minutes;[Mark Schauer (]ATEC
Atec, Inc. specializes in the design, manufacture, construction and maintenance of precision components, large fabrications, systems and facilities. Atec provides solutions for low to medium volume requirements involving engine test, aero support ...
(February 12, 2019) Unmanned aircraft stays aloft for nearly 26 days above U.S. Army Yuma Proving Ground
/ref>
* Facebook
Facebook is an online social media and social networking service owned by American company Meta Platforms. Founded in 2004 by Mark Zuckerberg with fellow Harvard College students and roommates Eduardo Saverin, Andrew McCollum, Dustin Mosk ...
worked on developing the Aquila solar-powered high-altitude flying-wing UAV to provide internet connectivity, spanning and weighing . It made two low-altitude test flights in 2016 and 2017 and is designed to stay aloft at FL650 for 90 days. On June 27, 2018, Facebook announced it will halt the project and plan to have other companies build the drones.
* Thales Alenia Space
Thales Alenia Space () is a Franco-Italian aerospace manufacturer. A joint venture between the French technology corporation Thales Group (67%) and Italian defense conglomerate Leonardo (33%), the company is the largest satellite manufactur ...
develops the Stratobus unmanned, solar-powered stratospheric airship
An airship or dirigible balloon is a type of aerostat or lighter-than-air aircraft that can navigate through the air under its own power. Aerostats gain their lift from a lifting gas that is less dense than the surrounding air.
In early ...
, long and weighting including a payload, it is designed for a five-year mission with annual servicing and a prototype is planned for late 2020
* China Aerospace Science and Technology Corporation
The China Aerospace Science and Technology Corporation, or CASC, is the main contractor for the Chinese space program. It is state-owned and has subsidiaries which design, develop and manufacture a range of spacecraft, launch vehicles, strategi ...
flew a -span solar-powered UAV to FL650 in a 15 hours test flight in July 2017
* Russia's Lavochkin
NPO Lavochkin (russian: НПО Лавочкина, OKB-301, also called Lavochkin Research and Production Association or shortly Lavochkin Association, LA) is a Russian aerospace company. It is a major player in the Russian space program, being th ...
design bureau is flight-testing the LA-252, an -span, solar-powered UAV designed to stay aloft 100 days in the stratosphere.
*H-Aero
The Hybrid-Airplane Technology H-Aero (styled as H-AERO) is a small Germany, German hybrid electric aircraft, electric unmanned aerial vehicle UAV by a Baden-Baden based start-up Hybrid-Airplane Technology GmbH. Compared to some other UAVs it ...
LTA-based launch systems for Mars exploration, with development taking place via terrestrial high-altitude platforms. The first systems are currently being tested
UK mapping agency Ordnance Survey
Ordnance Survey (OS) is the national mapping agency for Great Britain. The agency's name indicates its original military purpose (see ordnance and surveying), which was to map Scotland in the wake of the Jacobite rising of 1745. There was a ...
(OS), a subsidiary of the Department for Business, Energy & Industrial Strategy, is developing the A3, a 38 m (125 ft) wingspan, 149 kg (330 lb) twin-boom solar-powered HAPS designed to stay aloft at for 90 days carrying a payload.
OS owns 51% of UK company Astigan, led by Brian Jones
Lewis Brian Hopkin Jones (28 February 1942 – 3 July 1969) was an English multi-instrumentalist and singer best known as the founder, rhythm/lead guitarist, and original leader of the Rolling Stones. Initially a guitarist, he went on to prov ...
, developing the A3 since 2014 with scale model test flights in 2015 and full-scale low-altitude flights in 2016.
High-altitude flights should begin in 2019, to complete tests in 2020 with a commercial introduction as for environmental monitoring
Environmental monitoring describes the processes and activities that need to take place to characterize and monitor the quality of the environment. Environmental monitoring is used in the preparation of environmental impact assessments, as well a ...
, mapping, communications and security.
Designed by Prismatic Ltd., now BAE Systems, the 35 m (115 ft)-wingspan BAE Systems PHASA-35 made its maiden flight
The maiden flight, also known as first flight, of an aircraft is the first occasion on which it leaves the ground under its own power. The same term is also used for the first launch of rockets.
The maiden flight of a new aircraft type is alw ...
in February 2020 from the Woomera Test Range
The RAAF Woomera Range Complex (WRC) is a major Australian military and civil aerospace facility and operation located in South Australia, approximately north-west of Adelaide. The WRC is operated by the Royal Australian Air Force (RAAF), a d ...
in South Australia; it should fly its payload at around 70,000 ft for days or weeks.
History
HALE
The idea of HALE was acknowledged in technical papers as early as 1983, with ''A preliminary study of solar powered aircraft and associated power trains'' written by D.W. Hall, C.D. Fortenbach, E.V. Dimiceli and R.W. Parks (NASA CR-3699), the actual state of affairs within technology of a time during the 1970s, allowed for scientists to later consider the possibility of Long endurance flight as a conceivable inclusion to aviation of suborbital spacecraft
A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, p ...
. One of the first papers to explicitly mention ''Long Endurance'' is J.W.Youngblood, T.A. Talay & R.J. Pegg ''Design of Long Endurance Unmanned Airplanes Incorporating Solar and fuel cell propulsion'', published 1984. An early paper which incorporates both high-altitude and long-endurance as the area of investigation, is M.D. Maughmer ( University Pennsylvania State) and D.M. Somers (NASA Langley) ''Design and experimental results for a high-altitude, long-endurance airfoil''. The authors state interest in development of such a craft lay in the need to fulfill communication relay missions, weather monitoring, and to obtain information for the targeting of cruise missiles
A cruise missile is a guided missile used against terrestrial or naval targets that remains in the atmosphere and flies the major portion of its flight path at approximately constant speed. Cruise missiles are designed to deliver a large warhe ...
. This paper was published in the year 1989.
The research paper, ''2025'', written by B.W. Carmichael (Colonel
Colonel (abbreviated as Col., Col or COL) is a senior military officer rank used in many countries. It is also used in some police forces and paramilitary organizations.
In the 17th, 18th and 19th centuries, a colonel was typically in charge o ...
), and Majors, T.E. DeVine, R.J. Kaufman, P.E. Pence and R.E. Wilcox, and presented July 1996, foresaw routine HALE-UAV operations happening within the early 21st century. In contemplation of a future of the military, projected to 2025, the authors thought a HALE in flight for 24 hours. Long endurance ("long-loiter") is held synonymous with the concept of maintaining air occupation, "the ability to hold an adversary continuously at risk from lethal and non-lethal effects from the air".
The Defense Airborne Reconnaissance Office at some time made demonstrations of long-endurance UAV craft.
G Frulla (Turin, Italy 2002) wrote a paper on very long endurance.
An important goal of the CAPECON
The CAPECON project (civil UAV applications and economic effectivity of potential configuration solutions) was a European Union initiative to develop UAV, UAVs.
The project ran from 1 May 2002 to 31 December 2005. The total cost was 5 136 539 e ...
project, instigated by the European Union, was the development of HALE vehicles.
NASA ERAST Program
The initial goals under the NASA's Environmental Research Aircraft and Sensor Technology (ERAST) project were to demonstrate sustained flight at an altitude near 100,000 feet and flying non-stop for at least 24 hours, including at least 14 hours above 50,000 feet. The early development path of atmospheric satellites included the NASA Pathfinder
The NASA Pathfinder and NASA Pathfinder Plus were the first two aircraft developed as part of an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Envi ...
(exceeding 50,000 feet in 1995), the Pathfinder Plus (80,000 feet in 1998), and the NASA Centurion
The NASA Centurion was the third aircraft developed as part of an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Environmental Research Aircraft and Se ...
which was modified into a prototype configuration for the NASA Helios
The Helios Prototype was the fourth and final aircraft developed as part of an evolutionary series of solar- and fuel-cell-system-powered unmanned aerial vehicles. AeroVironment, Inc. developed the vehicles under NASA's Environmental Research A ...
(96,000 feet in 2001).[ An Airbus/]Qinetiq Zephyr
The Airbus Zephyr is a series of lightweight solar-powered unmanned aerial vehicles (UAV). The latest model is a high-altitude platform station capable of flying at for months at a time without fueling. It has a wingspan of and weighs .
Deve ...
flew for 14 days in the summer of 2010, and in 2014 a Zephyr 7 stayed up for 11 days in the short days of winter whilst carrying a small payload for the British Ministry of Defence.
See also
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References
Bibliography
C. Smith - article published by The Examiner (AXS Digital Group LLC) March 8, 2010 etrieved 2-15-12-09
External links
Mobile Telecommunications via Stratosphere
by R. Struzak
HAA contract info
Janes Aviation
{{Emerging technologies, transport=yes
Unmanned aerial vehicles
Emerging technologies