This is one of the most difficult projects the space agency has undertaken in order to develop the technologies that will be required for a completely reusable launch vehicle (RLV) in the future.
Before the end of April, the Indian Space Research Organization (ISRO) will enter a critical phase of its ambitious goal to construct a reusable launch vehicle that can travel from Earth to orbit in two stages. The space agency will test the landing capabilities of India’s Reusable Launch Vehicle (RLV) technology at a DRDO (Defence Research and Development Organization) airstrip in Chitradurga, Karnataka, about 220 kilometres from Bengaluru. The RLV technology is a critical component of the country’s Reusable Launch Vehicle (RLV) technology.
With the RLV Landing Experiment, also known as RLVLEX, a helicopter is used to transport an unmanned, winged prototype to an altitude of 2.3-2.4 kilometres before releasing it to land on an airfield. “The prototype will be released 3.7 kilometres from the airstrip, and it will have to fly the distance on its own, develop velocity, maintain control, and land on the airstrip like any other conventional aircraft, with the back wheels touching down first. Following that, a parachute would be deployed for braking,” adds ISRO Chairman S. Somanath in regards to the technology demonstrator.
This is one of the most difficult projects undertaken by ISRO in the pursuit of critical technologies for a completely autonomous vehicle. It is necessary to conduct a series of experiments in order to demonstrate the validity of the technology. Because of the exorbitant expense of launchers in space exploration, the Indian Space Research Organization (ISRO) is committed to develop RLV technology. The RLV is attractive because it allows for more affordable access to space.
Because it combines the complexity of both launch vehicles and aircraft, the RLV has a configuration that is similar to that of an aircraft. In the future, this vehicle will be scaled up to serve as the first stage of India’s reusable two-stage orbital launch vehicle, which is now under development. Several technologies, including hypersonic flight, autonomous landing, powered cruise flight, and hypersonic flight driven by air breathing propulsion, have been evaluated on the aircraft. However, it is expected that the testing and development for the first full-scale RLV flight will take a decade or more.
Several flights have been planned in the lead-up to demonstrate various technologies, including the hypersonic flight experiment (HEX), autonomous landing experiment (LEX), return flight experiment (REX), scramjet propulsion (SPEX) for its air breathing engine, and the orbital re-entry experiment (ORE), in which the launch vehicle will be ferried to orbit on either a geostationary satellite launch vehicle (GSLV) or a polar satellite launch vehicle (PSLV), and then perform an orbit
The first of these experiments, the RLV-TD HEX-01 mission, took place on May 23, 2016, and was the first of a series of tests. ISRO successfully tested the RLV’s descent from a height of 65 kilometres for an atmospheric re-entry at a speed of around 5 kilometres per second (five times the speed of sound). During this phase, the vehicle’s navigation, guidance, and control system maintained precise steering control to ensure a safe fall. Using its thermal protection technology, the vehicle was able to successfully survive the extreme temperatures experienced during re-entry and drifted down to the designated landing place over the Bay of Bengal, around 450 kilometres from Sriharikota in Andhra Pradesh.
It is critical that the vehicle lands on solid ground in order for it to be reusable. The LEX mission to demonstrate the essential technology of autonomous runaway approach and landing, which is now taking place at Challakere near Chitradurga, is a quantum leap forward in the establishment of indigenous capabilities for the RLV mission. In order to showcase the technology that will be utilised in the final RLV, which is planned to make its first flight in the 2030s, a scaled-down replica of the intended launch vehicle is being used. This version does not have the payload capacity.
The development of RLV, despite the fact that it has been on the ISRO’s drawing board for years, has been pushed to the back burner as the organization’s priority has shifted to the GSLV programme. The cancellation of the space shuttle programme in the United States in 2011, which used RLV technologies, also played a role in the virtual cancellation of ISRO’s RLV plans. It is intended that in the future, rockets be reusable. While a tiny portion will be destroyed during the propulsion process due to the burning of fuel, the majority will re-enter the atmosphere and land like an aeroplane, ready to be used in future missions. Reusable rockets will lower the cost and consumption of energy.
The renewed interest in RLVs around the world has been sparked by the pioneering efforts of private businesses such as the Elon Musk-founded SpaceX in developing cost-effective launch vehicles that, like aeroplanes, can fly hundreds of times into space over the course of their lives. Since December 2015, SpaceX has proved that not only the orbital second stage of a rocket, but also the booster used in the first stage of the launch can be returned to Earth and reused after being sent into orbit.
Along with private companies such as Blue Origin, founded by Amazon founder Jeff Bezos, and the Orbital Sciences Corporation, the European Space Agency, Japan’s JAXA space agency, and the European Space Agency are all competing to develop a fully reusable space launch vehicle. SpaceX is the only company currently in the race. “Reduced life expectancy is a priority. It will result in a significant reduction in the cost of launches. Additionally, launch vehicles that can be reused up to fifteen times are required. “Any cost-cutting measure would have a ripple effect on more launches, ultimately extending its benefits to a greater number of people,” Somanath explains. The landing of the Challakere spacecraft this week reaffirms that India and the Indian Space Research Organization (ISRO) are not behind the times when it comes to space exploration.