NEW DELHI: The Defence Acquisition Council (DAC), chaired by defence minister Rajnath Singh, has cleared the procurement of Excessive Altitude Pseudo Satellites (HAPS) for the Indian Air Drive. The transfer is predicted to considerably improve the armed forces’ intelligence, surveillance and reconnaissance capabilities.HAPS is an Unmanned Aerial Car (UAV) designed to function at an altitude of round 20 km (65,000 toes). In line with the Nationwide Aerospace Laboratories (NAL), this altitude is above each business airline flight paths and most climate programs. HAPS combines the persistent surveillance functionality of a geostationary satellite tv for pc with the mobility and suppleness of an plane, successfully bridging the hole between the 2.Operationally, a single HAPS can present steady optical, infrared and alerts intelligence protection over a 500 km radius for weeks, far exceeding the revisit cycles of satellites and the endurance limits of typical patrol plane.India has already demonstrated indigenous capabilities on this subject. On Might 3, 2025, DRDO carried out the maiden trial of its Stratospheric Airship Platform, reaching an altitude of 17 km. Across the identical time, CSIR-NAL’s solar-powered fixed-wing demonstrator accomplished a flight lasting greater than 10 hours at 7.6 km. A full-scale stratospheric flight to twenty km is focused for 2027.Globally, Airbus’ Zephyr has set the benchmark by finishing a 67-day steady flight in April 2025. Such prolonged endurance is made attainable by light-weight, solar-powered plane geared up with extremely environment friendly photo voltaic panels mounted on their wings and supported by battery programs.Not like conventional lighter-than-air balloons and airships, which have struggled with station-keeping due to wind and photo voltaic heating, heavier-than-air solar-powered UAVs provide larger stability. The plane below growth by CSIR-NAL makes use of photo voltaic vitality throughout the day and batteries for night time operations.The complete-scale NAL HAPS is predicted to have a wingspan of greater than 30 metres, wider than an Airbus A320, whereas weighing solely about 150 kg, roughly the load of a bike. The ultra-lightweight design is important as a result of the plane depends totally on photo voltaic vitality for propulsion and payload operations.The engineering challenges stay important. Working at stratospheric altitudes and low airspeeds requires distinctive aerodynamic effectivity. The light-weight airframe presents aeroelasticity challenges, whereas the propellers should carry out effectively from sea degree to the stratosphere, the place air density is just about 7% of that at sea degree.The plane should additionally stand up to temperatures as little as -85°C and intensely low atmospheric strain, putting appreciable calls for on avionics, payload programs and batteries.Regardless of these challenges, NAL’s subscale demonstrator has already accomplished an 11-hour flight at 25,000 toes, demonstrating the feasibility of scaling up the know-how.
