Among the latest aerospace technologies, there has been growing pace of activity around High Altitude Pseudo Satellites or HAPS platforms that are emerging as a disruptive technology which could revolutionise near-space operations. Although these unmanned stratospheric vehicles have been in development since the 1990s, recent advancements in technologies have spurred the momentum with the latest iterations reaching more advanced stages in terms of operation, payloads, and capabilities.[i] A market study based on the significant R&D investments towards development of various types of HAPS platforms – including stratospheric balloons, airships, and UAVs – forecast an upswing in the 2020-2025 period registering a CAGR of over 8 per cent.[ii]
High Altitude Pseudo Satellites are unmanned aircraft operating in the stratosphere at altitudes of approximately 65,000 ft or above. These solar-powered vehicles have been designed to plug the missing link between unmanned aerial vehicles (UAVs) flying in lower altitudes and conventional satellites in space. Stationed in a fixed place, these long-endurance flights – lasting months or even years, help provide versatile intelligence, surveillance and reconnaissance (ISR) options thereby eliminating performance and capability limitations of satellites.[iii] Unlike regular satellites that are expensive to build and launch, HAPS cost far less and are easier to launch. These vehicles can be controlled from anywhere using Beyond Line of Sight (BLOS) technology.[iv] The main applications of HAPS are in telecommunication and remote sensing for both civilian as well as military purposes. HAPS are particularly useful in providing communication in remote areas lacking infrastructure or in deep seas. Disaster relief, search and rescue (SAR) missions, smart city management, precision agriculture are some of the other areas where HAPS can provide valuable services.[v] As per a European Space Agency study, HAPS can provide “emergency communications and broadband internet services” for major events like Olympics by establishing “secure communication bubbles”.[vi]
Compared to ground based communication networks, HAPS can cover larger areas with less interference. They could also help ease data transfer when used as an intermediate conduit between a satellite and ground based telecom networks.[vii] As compared to satellites, HAPS can perform better in some applications like telecommunication and Earth observation due to lower transmission delay. They can also be overhauled and re-used with reconfigured payloads every few months.[viii] A 2017 study comparing a constellation of Low Earth Orbit satellites and HAPS platforms for remote sensing shows that due to their ability to remain continuously over an area for long periods, these stratospheric drones have “a clear advantage for revisiting a large zone with higher predictability and accuracy”.[ix]
In India, Hindustan Aeronautics Limited (HAL) recently announced that it is developing a “futuristic” high altitude pseudo satellite in collaboration with a start-up company. “We are developing a high altitude pseudo satellite with a start-up company, it is futuristic. No country in the world has developed it yet. It will be solar energised and a big asset flying around 70,000 ft for 2-3 months unmanned taking information,” Arup Chatterjee, HAL Director (Engg and R&D), said.[x] The pseudo satellite with ISR capabilities would be a key component of India’s indigenous unmanned drone warfare programme called CATS or Combat Air Teaming System.[xi]
With a long and complex land border of about 15106.7 km and a coastline of 7,516.6 km[xii], safeguarding the borders is crucial for India and necessitates varied solutions. Hovering at the edge of the Earth’s atmosphere, HAPS can provide services towards efficient border patrolling, tracking movements deep into the enemy territory or in the deep seas with their sharp focus on one area. Equipped with high-definition optical and infra-red cameras, state-of-the-art sensors, these aerial platforms are suitable for round-the-clock missions, border patrolling, target tracking, maritime surveillance and navigation, and even missile detection.[xiii] A network of HAPS can supplement the existing lacunae in satellite services. When aligned with a platform like the indigenously developed CATS, HAPS would be crucial to help coordinate attack missions, providing communication to troops engaged in remote regions and for providing Battle Damage Assessment (BDA) via live video feeds and images (which were missing during the Balakot strikes and had led to questions being raised on the mission’s success[xiv]) to determine if the mission was successful and to plan the next course of action.
The stratospheric platform being designed will be in the class of Airbus’ Zephyr unmanned aerial system.[xv] The solar-powered Zephyr S, carrying prototypes of passive Earth observation payloads, recently set a new flight endurance record just short of 26 days.[xvi] With an aim to provide persistent tactical communication for forces dispersed in remote areas, Airbus Defence and Space has been working on developing various HAPS platforms for the British military.[xvii]
AeroVironment, Inc., Loon LLC (Alphabet Inc.), BAE Systems, and Astigan Limited are some of the other major companies that have been working on HAPS technology.[xviii] Although Alphabet recently shut down its internet balloon company Project Loon citing inability to lower costs, and Facebook grounded its Aquila drone project in 2018, several other projects like BAE Systems’ PHASA-35 are in advanced stages of development. Project Loon gained attention when its stratospheric balloons were deployed to provide data connectivity in hurricane-ravaged Puerto Rico in 2017 and in rural Peru in 2019.[xix] China’s state-owned aerospace and defense conglomerate, Aviation Industry Corporation of China (AVIC), has been working on varied HAPS platforms for surveillance purposes. In 2018 it successfully tested its solar-powered Morning Star drone which can reportedly stay airborne for months.[xx]
India has been working towards uplifting its space capabilities and focusing on the small satellite (SmSats) segment to fill the capability and performance limitations in meeting the C4ISR (Command, Control, Computers, Communications, and Intelligence, Surveillance and Reconnaissance) needs vital for military operations. HAPS, due to their affordability, versatility and ability to provide prolonged high-resolution coverage of specific areas can play a vital role in supplementing defence communication infrastructure both territorial and space based to render robust round-the-clock surveillance on the borders and in the Indian Ocean region. HAPS is relatively new in the Indian context with only HAL along with a start-up company working on the technology currently. Considering the niche technology needs immense R&D, the road ahead is not going to be an easy one. There is a need to incentivise competent private companies so that there are more number of players in the field. The ‘Innovation’ clause in DAP 2020, which is a new acquisition category to boost defence manufacturing in MSMEs and start-ups, can be explored to bring in more players to work on the cutting-edge near-space technology which is poised for wider adoption in the near future.
[i] ESA Space Solutions (2017), “Services enabled by High Altitude Pseudo Satellites (HAPS) complemented by satellites”, 2017. Available on https://business.esa.int/funding/invitation-to-tender/services-enabled-high-altitude-pseudo-satellites-haps-complemented-satellites, accessed on 06 Mar 2021.
[ii] Mordor Intelligence (2020), “High-altitude pseudo satellites market – growth, trends, covid-19 impact, and forecasts (2021 – 2026)”, 2020. Available on https://www.mordorintelligence.com/industry-reports/high-altitude-pseudo-satellites-market,
accessed on 06 March 2021.
[iii] Pedro Vicente Valdez and Paulina Wheeler (2019), “High Altitude Pseudosatellites”, On the Radar, 29 July 2019. Available on https://ontheradar.csis.org/issue-briefs/high-altitude-pseudosatellites/, accessed on 06 March 2021.
[iv] Jonny Kramer (2018), “Pseudo-Satellites and their influence in aerospace and aviation”, VHR, 12 Oct 2018. Available on https://blog.v-hr.com/blog/what-are-pseudo-satellites-and-what-do-they-mean-for-aerospace-and-aviation, accessed on 06 March 2021.
[v] Mordor Intelligence (2020), “High-altitude pseudo satellites market – growth, trends, covid-19 impact, and forecasts (2021 – 2026)”, 2020. Available on https://www.mordorintelligence.com/industry-reports/high-altitude-pseudo-satellites-market, accessed on 06 Mar 2021.
[vi] The European Space Agency (2018), “Could High-Altitude Pseudo-Satellites Transform the Space Industry?”, ESA, 12 Nov 2018. Available on
[vii] The European Space Agency (2018), “HAPS – missions to the edge of space to watch over Earth”, ESA, 15 Nov 2018. Accessed on
[viii] Jesus Gonzalo, Deibi Lopez, et al (2018), “On the capabilities and limitations of high altitude pseudo-satellites”, researchgate.net, Mar 2018. Available on https://www.researchgate.net/publication/324032332_On_the_capabilities_and_limitations_of_high_altitude_pseudo-satellites, accessed on 06 March 2021.
[ix] Coulon A and Johnson S (2017), “Using High-Altitude Pseudo Satellites as an innovative technology platform for climate measurements”, SAO/NASA Astrophysics Data System (ADS). Available on https://ui.adsabs.harvard.edu/abs/2017AGUFM.A31L..03C/abstract, accessed on 06 March 2021.
[x] Asian News International (2021), “IAF to get 1st delivery of LAC Tejas by March 2024, says HAL Chairman”, Asian News International, 04 Feb 2021. Available on
[xi] Vishnu Som (2021), “Exclusive: New Indian Drone Can Soar For 90 Days, Coordinate Attacks”, ndtv.com, 04 Feb 2021. Available on https://www.ndtv.com/india-news/new-indian-drone-can-fly-non-stop-for-90-days-while-monitoring-attacks-2362830, accessed on 06 March 2021.
[xii] Ministry of Home Affairs, “India – International Land Border”. Available on https://www.mha.gov.in/sites/default/files/BMIntro-1011.pdf, accessed on 17 Mar 2021.
[xiii] Flavio Araripe d’Oliveira (2016), “High-Altitude Platforms — Present Situation and Technology Trends”, July-Sept 2016. Available on http://www.scielo.br/scielo.php?script=sci_arttext&pid=S2175-91462016000300249#aff02, accessed on 14 Mar 2021.
[xiv] Vishnu Som (2021), “Exclusive: New Indian Drone Can Soar For 90 Days, Coordinate Attacks”, ndtv.com, 04 Feb 2021. Available on https://www.ndtv.com/india-news/new-indian-drone-can-fly-non-stop-for-90-days-while-monitoring-attacks-2362830, accessed on 06 March 2021.
[xv] Vishnu Som (2017), “Drone Designed By Indian Start-Up Could Track China’s Military Moves”, ndtv.com, 07 Dec 2017. Available on https://www.ndtv.com/india-news/drone-designed-by-indian-start-up-could-track-chinas-military-moves-1784952, accessed on 06 March 2021.
[xvi] Airbus (2020), “The Airbus Zephyr, Solar High Altitude Platform Station (HAPS) concludes a successful new test flight campaign in Arizona, USA”, airbus.com, 03 Dec 2020. Available at https://www.airbus.com/newsroom/press-releases/en/2020/12/the-airbus-zephyr-solar-high-altitude-platform-station-haps-concludes-a-successful-new-test-flight-campaign-in-arizona-usa.html, accessed on 06 Mar 2021.
[xvii] Richard Gardner (2018), “High-altitude pseudo satellites: new battle for inner space, part I”, sae.org, 12 Dec 2018. Available on https://www.sae.org/news/2018/12/high-altitude-pseudo-satellites-new-battle-for-inner-space-part-i-copy, accessed on 06 Mar 2021.
[xviii] Mordor Intelligence (2020), “High-altitude pseudo satellites market – growth, trends, covid-19 impact, and forecasts (2021 – 2026)”, 2020. Available on https://www.mordorintelligence.com/industry-reports/high-altitude-pseudo-satellites-market, accessed on 06 Mar 2021.
[xix] Dan Swinhoe (2021), “Alphabet shuts down Internet balloon subsidiary Project Loon”, datacenterdynamics.com, 22 Jan 2021. Available on https://www.datacenterdynamics.com/en/news/alphabet-shuts-down-internet-balloon-subsidiary-project-loon/, accessed on 14 Mar 2021.
[xx] Marco Margatitoff (2018), “China successfully tests solar-powered drone capable of being airborne for months”, thedrive.com, 04 Nov 2018. Available on https://www.thedrive.com/drones/24668/china-successfully-tests-solar-powered-drone-capable-of-being-airborne-for-months, accessed on 17 Mar 2021.