India is preparing to test fly its first full-scale High-Altitude Pseudo-Satellite (HAPS), developed by the National Aerospace Laboratories (NAL), capable of operating at altitudes of 75,000 feet for up to 90 days.
This breakthrough will provide persistent surveillance and communications capabilities, positioning India alongside leading nations in stratospheric aerospace innovation.
India’s National Aerospace Laboratories, under the Council of Scientific and Industrial Research, is advancing its ambitious High-Altitude Pseudo-Satellite program. The upcoming test flight will mark the maiden deployment of the full-scale platform, which boasts a wingspan of 33 metres—comparable to a Boeing 737—and is designed to remain airborne for at least three months.
This endurance is enabled by solar-powered systems and advanced battery management, allowing continuous operation in the stratosphere.
The project has already seen successful trials of scaled prototypes. In 2024, NAL flew a five-metre-long solar-powered demonstrator with an 11-metre wingspan, achieving altitudes of 7.5 kilometres and endurance exceeding ten hours.
These tests validated the aerodynamic design, lightweight carbon composite structures, and solar energy harvesting systems essential for stratospheric flight. The full-scale version will rise to 23 kilometres, well above commercial aviation altitudes, and provide uninterrupted coverage over vast geographical areas.
HAPS platforms are often described as “towers in the sky.” Unlike satellites, which require complex launches and offer intermittent coverage, or drones, which are limited by endurance and altitude, HAPS can loiter for months, delivering persistent surveillance, telecommunications, and environmental monitoring.
They can beam 5G and even future 6G signals, extend broadband connectivity to remote regions, and provide real-time imagery and video for defence and civilian applications. Their flexibility makes them suitable for disaster management, precision agriculture, and maritime domain awareness.
Globally, only a handful of nations—including the United States, United Kingdom, Germany, South Korea, New Zealand, and Japan—are investing in similar stratospheric technologies.
Airbus has already demonstrated operational flights of its Zephyr platform, which has been adopted by the UK Ministry of Defence for high-resolution imagery and near-real-time video. India’s entry into this elite group underscores its growing scientific and technological capabilities, particularly in aerospace innovation.
NAL’s design incorporates indigenous development of critical subsystems such as high-powered electric motors capable of operating in extreme temperatures, advanced propellers optimised for thin stratospheric air, and robust flight-control systems.
The platform’s modular payload bay will allow integration of surveillance sensors, communication relays, and scientific instruments, making it versatile for both military and civilian missions. With a cruising speed of 80–100 km/h and payload capacity of around 10 kg, it offers persistent coverage with far lower latency than satellites.
For India’s armed forces, the HAPS represents a cost-effective complement to satellites and UAVs. Current drone platforms cannot reach stratospheric altitudes, while satellite launches remain expensive and time-consuming.
A stratospheric pseudo-satellite can provide continuous intelligence, surveillance, and reconnaissance along sensitive borders, monitor maritime zones, and deliver real-time situational awareness during crises.
Civilian applications include disaster monitoring during floods or cyclones, extending digital inclusion to underserved regions, and supporting environmental research.
The program has reached a critical milestone, with scientists confirming that the full-scale model will be ready for flight by the end of 2026.
This achievement reflects years of research into lightweight composites, solar energy systems, and autonomous navigation. Once operational, India’s HAPS will not only strengthen national defence capabilities but also contribute to broader goals of connectivity, resilience, and scientific advancement.
Agencies
