Spaceplanes are advanced aerospace vehicles that can glide and land like an airplane on an airstrip within the Earth’s atmosphere, and maneuver like a spacecraft in space. The Space Shuttle and Buran, which were popular spaceplanes in the 1980s, are no longer operational. As of 2023, only the United States and China are known to operate autonomous and reusable spaceplanes, with India potentially becoming the third country to join this exclusive club with its indigenous spaceplane called the ‘Reusable Launch Vehicle – Technology Demonstrator’ (RLV-TD). The RLV-TD prototype has been developed by the Indian space agency ISRO, with support from the Indian Defense lab DRDO and the Indian Air Force.
The United States has been operating the ‘Boeing X-37B’ spaceplane for nearly a decade, demonstrating its ability to remain in space for more than 900 days in a single trip. China is also believed to have its own spaceplane, but details about it are scarce due to the military and civilian applications of spaceplanes, which countries typically keep confidential.
Spaceplanes do not operate independently, but instead ride piggyback on a large rocket during their journey to Earth orbit. The rocket carries the spaceplane to an orbit around the Earth, and once in orbit, the spaceplane operates autonomously to perform its mission. When it is time to return to Earth, the spaceplane de-orbits by maneuvering to re-enter the Earth’s atmosphere and is drawn by the Earth’s gravitational pull. As it descends into the denser layers of the Earth’s atmosphere, the spaceplane uses its control surfaces to glide and make a runway landing.
On April 2, 2023, ISRO demonstrated the precise runway landing of an unmanned, fully autonomous RLV-TD spaceplane. The spaceplane was dropped mid-air from an altitude of 4.5 kilometers by an Indian Air Force ‘Chinook’ tandem-rotor helicopter. After being dropped, the spaceplane autonomously glided down and covered a distance of nearly 4.6 kilometers while performing navigation, guidance, and control calculations. The spaceplane then maneuvered deftly and landed precisely on a runway at a high speed of 350 kilometers per hour. ISRO officials stated that the landing was executed as planned, with the spaceplane ending up in impeccable condition at the Aeronautical Test Range tarmac in Chitradurga, Karnataka.
This achievement by ISRO marks a significant advancement in autonomous technologies and avionics, showcasing India’s progress in developing sophisticated spaceplane capabilities. The RLV-TD prototype weighs 1.6 tons, measures 6.5 meters in length, and 3.6 meters in breadth, and is the result of nearly two decades of development work by ISRO. Previously, in 2016, the RLV-TD vehicle had successfully been carried to an altitude of 65 kilometers by a rocket, re-entered the denser parts of the atmosphere at hypersonic speeds, and made a splashdown landing in the Bay of Bengal, simulating a runway landing. However, the recent precise runway landing is a technologically complex feat that takes ISRO a step closer to realizing the goal of a reusable rocket/landing craft for specific mission objectives.
ISRO Chairman, Dr. S. Somanath, stated that the RLV-TD provides an opportunity for India to develop an ‘ORV’ (orbital landing experiment), which involves flying the spaceplane to space on top of a rocket and autonomously bringing it back to land on a runway. He mentioned that work on this project is already progressing, and the successful landing of RLV-TD is a significant milestone in achieving this goal. Dr. Unnikrishnan Nair, VSS
Post Your Comments