High Altitude Pseudo Satellites (HAPS) are advanced solar-powered unmanned aerial systems designed to operate at altitudes above the troposphere for extended periods, typically months.

Operating at about 20 km above ground level, HAPS vehicles are entirely solar-powered and equipped with mission-specific sensors.
While primarily used for surveillance and monitoring, HAPS can also play a crucial role in disaster management and other applications.


Indian Context:

The National Aerospace Laboratories (NAL) in Bengaluru has successfully conducted the first test of a solar-powered pseudo-satellite. This marks a significant milestone in enhancing India’s surveillance and monitoring capabilities, particularly in border areas.

With this achievement, India joins a select group of countries experimenting with HAPS technology.

Technological Challenges:
Solar Power Generation:

  • One of the main challenges is generating sufficient solar power to sustain flight, operate payloads, and charge batteries.
  • Ensuring that the batteries can store enough power to maintain operations through the night is critical.

Design Challenges:

  • The aircraft must be extremely lightweight to minimize power consumption while maintaining stability.
  • HAPS must endure extremely low temperatures, often dropping to -50 degrees Celsius or lower, necessitating solutions to keep electronic components warm.


  • Traditional UAVs, or drones, are typically battery-powered and have limited flight durations, often restricted to a few hours, and operate at lower altitudes, limiting their surveillance range.
  • In contrast, HAPS operate like geostationary satellites with added flexibility. They can be redeployed to different locations and reequipped with various payloads, providing versatility that geostationary satellites lack.
  • The development and deployment of HAPS can significantly enhance India’s capabilities in surveillance, monitoring, and disaster management, offering a robust solution to various strategic and civilian challenges.
Legacy Editor Changed status to publish July 4, 2024