ISRO's autonomous spaceplane 'Pushpak' lands at 360 kmph, way more quicker than fighter jets

At 7:10 am (Indian Standard Time) on Friday (March 22), the Indian Space Agency, ISRO and the Indian Air Force accomplished the second successful runway landingof the country's fully autonomous spaceplane. This is a vehicle that India eventually intends to develop and use to ferry small cargo (satellites and experiments) to space.

Known as a Re-usable Launch Vehicle Technology Demonstrator(RLV-TD) or 'Pushpak', the spaceplane is a sophisticated aerospace vehicle with civilian and strategic applications. It must be noted that only the US and China are known to operate autonomous spaceplanes, and in the coming years, as ISRO makes further progress on 'Pushpak', India will be the third nation in this list. Dr S Somanath, Chairman, ISRO, congratulated the team for the flawless execution of the complex mission, designated at RLV LEX-02 or Landing Experiment-02.

Add WION as a Preferred Source

What the latest RLV LEX-02 test is all about

In the latest test, the 1.6-tonne spaceplane was underslung to an Indian Air Force Chinook heavy-lift helicopter, which carried the spaceplane to an altitude of 4.5 km and released it fourkm away from the runway. The plane was dropped in a position that was misaligned with the runway at a sideways distance of 150 metres. In the maiden landing test in April 2023, the plane was at the same distance and altitude away from the runway, but it was aligned straight to the runway, without a sideways distance from the runway.

Also Read:Watch: ISRO successfully completes landing of 'Pushpak', country's first Reusable Launch Vehicle

On being released, the plane is meant to carry out all gliding and related manoeuvres fully autonomously, based on the real-time calculations of its onboard sensors and computers. According to ISRO, the RLV was made to undertake more difficult manoeuvres, when compared to the earlier landing attempt in April 2023.

Explaining the sophistication and significance of this feat, Dr Unnikrishnan Nair, Director of ISRO's Vikram Sarabhai Space Centre, told WION that the goal of the latest test was to ensure that the spaceplane could manoeuvre itself to perfectly align with the runway and make the landing. Citing the picture of the 'Pushpak' vehicle that stood in line with the runway's centreline, he added that it was a testimony to the perfect landing that the plane had performed. Dr. Nair mentioned that each of the RLV landing tests is meant to demonstrate how the vehicle performs in different stages of its actual flight.

Speaking about the spaceplane's design, he said that it was meant for operating in various conditions - sub-sonic, supersonic, hypersonic. Therefore, he emphasised the importance of testing it under various conditions and speed regimes.

In the year 2016, the RLV-TD vehicle had successfully been carried to 65 km altitude by a rocket. From there, the vehicle re-entered the denser parts of the atmosphere at hypersonic speeds, almost five times the speed of sound and finally made a splashdown landing in the Bay of Bengal (simulated runway).

Watch:ISRO's LVM3 rocket engines tested and ready to ferry Gaganyaan astronauts

When compared to the landing mission done in April 2023, ISRO has enhanced the airframe structure (overall body) and the landing gear of the spaceplane, thereby equipping it to tolerate the higher loads of landing at speeds as high as 360kmph (around 100metres/second). It must be noted that fighter jets land at speeds ranging from 200-250kmph. ISRO said that the winged body and all flight systems used in RLV-LEX-01(April 2023) were re-used in the RLV-LEX-02 mission after due certification and clearances. Hence, the reuse capability of flight hardware and flight systems is also demonstrated in this mission.

ISRO said that the RLV team was guided by P. Sunil, Programme Director, Advanced Technology and Systems Programme, VSSC. J. Muthupandian, Project Director, RLV, served as the Mission Director and B Karthik, Deputy Project Director, RLV, was the vehicle director for this mission.

The final configuration of the RLV

In its present form, this RLV-TD vehicle is meant for demonstration purposes and the real vehicle would be about 1.6 times larger. Once fully ready, the operational version of the RLV or 'Pushpak' is meant to be mounted atop a modified GSLV rocket and then launched into space, where the spaceplane would be autonomously carrying out on-board experiments and operating its payloads.

The spaceplane could function in Low Earth orbit for up to a month and then autonomously perform de-orbiting, re-enter the Earth's atmosphere and come in to land on the runway. This ensures that the spaceplane can be fully re-used after carrying out a few refurbishments. In many ways, the RLV is similar to the space shuttle operated by the US and the Soviet-era Buran spaceplane. However, the RLV is much smaller and not a crewed plane, unlike the Space Shuttle and the Buran. RLV is comparable to the American Boeing X-37B spaceplane and the Chinese 'Shenlong' (Divine dragon), which have been performing unmanned missions for many years.