The Reusable Launch Vehicle Autonomous Landing Mission (RLV LEX)
With the successful completion of the Reusable Launch Vehicle Autonomous Landing Mission (RLV LEX) by the Indian Space Research Organisation, the realisation of an Indian Reusable Launch Vehicle is one step closer to becoming a reality (ISRO). A winged body was tested at the Aeronautical Test Range in Chitradurga, Karnataka, by being hoisted to a height of 4.5 kilometres by an Indian Air Force Chinook chopper and then being released to carry out an autonomous landing on a runway.
This is the first time that a winged body has been released mid-air by a helicopter and carried out an autonomous landing. The RLV LEX is essentially a space plane with a low lift-to-drag ratio requiring an approach at high glide angles that necessitated a landing at high velocities of 350 kmph.
The autonomous landing was carried out under circumstances resembling those of a space re-entry spacecraft landing, achieving landing criteria such accurate body rates, the sink rate of landing gears, and ground relative velocity. Several cutting-edge technologies were required to complete the Reusable Launch Vehicle Autonomous Landing Mission (RLV LEX), including precise navigational hardware and software, a pseudolite system, a Ka-band Radar Altimeter, a NavIC receiver, a native landing gear, Aerofoil honeycomb fins, and a brake parachute system.
Using instrumentation, sensor, and pseudolite systems, ISRO created localised navigation systems. Using a Digital Elevation Model (DEM) of the landing site, the Ka-band Radar Altimeter produced accurate height data. Before to the flight, thorough wind tunnel testing and CFD simulations allowed for the aerodynamic characterisation of RLV.
The LEX mission completed the final approach phase along the re-entry return flight path with an autonomous, high-speed (350 kmph) landing. In the years that followed the Integrated Navigation test, there were other Engineering Model Trials and Captive Phase testing.
The test was carried out in cooperation with ISRO by the Indian Air Force, the Centre for Military Airworthiness and Certification (CEMILAC), the Aeronautical Development Establishment (ADE), and the Aerial Delivery Research and Development Establishment (ADRDE). A number of sorties were conducted to perfect the release circumstances, and S Somanath, the chairman of ISRO and the secretary of the Department of Space, were among those present for the test.
The successful RLV LEX test shows that other operational launch vehicles of ISRO can be made more cost-effective by using modern technologies developed for RLV LEX. This achievement follows ISRO’s key breakthrough in the development of Reusable Launch Vehicles, the re-entry of its winged vehicle RLV-TD in the HEX mission in May 2016.