CHITRADURGA: The Indian Space Research Organisation (ISRO) on Sunday successfully landed its Reusable Launch Vehicle (RLV) in an autonomous mode, demonstrating its capability to deliver low-earth orbit satellites in space and return to the ground for reuse in a subsequent mission. This is expected to pave the way for an 80 per cent reduction in the costs of satellite launching missions.
The successful experiment, Reusable Launch Vehicle Autonomous Landing Mission (RLV-LEX), was carried out at the Aeronautical Test Range (ATR) of the Defence Research and Development Organisation (DRDO) in Challakere in Karnataka’s Chitradurga district.
At 7.10 am, a Chinook Helicopter of the Indian Air Force carried a winged RLV and flew to a height of 4.5 km to a predetermined spot. It released the RLV from that height and carried out a precise autonomous landing on the runway at DRDO’s ATR in Challakere.
ISRO had earlier demonstrated this re-entry of a winged RLV Technology Demonstrator (RLV-TD) in May 2016, but it was on a hypothetical runway over the Bay of Bengal. However, Sunday’s LEX mission successfully achieved the final approach phase that coincided with the re-entry flight path exhibiting an autonomous, high-speed (350 kmph) landing, according to ISRO.
Going forward, more experiments are in the pipeline to ensure that the RLV succeeds in payload delivery to low earth orbit, as ISRO plans to reduce the cost of the process by 80%.
The experiments will also include taking off with a simulated payload and returning in an autonomous mode after releasing the payload in space at a predetermined location/orbit.
First in the world
The technique adopted to launch the vehicle was “a first in the world” wherein a winged body was carried to an altitude of 4.5 km by helicopter and released for carrying an autonomous landing on a runway. “The autonomous landing was carried out under the exact conditions of Space Re-entry vehicle’s landing – (such as) high speed, unmanned, precise landing from the same return path – as if the vehicle arrived from space,” an ISRO release said.
The RLV 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.
ISRO said the LEX utilised several indigenous systems. “Localized Navigation systems based on pseudolite systems, instrumentation and sensor systems, etc were developed by ISRO. Adaptation of contemporary technologies developed for RLV LEX makes other operational launch vehicles of ISRO more cost-effective,” according to the space agency.