SOLVE Test & Gaganyaan Mission

SOLVE Test & Gaganyaan Mission
Why in News?
ISRO has successfully conducted the first ground test of the Solid Motor-based Sub-Orbital Launch Vehicle for Experiments (SOLVE) at the Static Test Facility, Satish Dhawan Space Centre, Sriharikota. The SOLVE vehicle has been developed as a dedicated test platform for validating the Crew Module's deceleration and parachute systems under different mission conditions before the operational Gaganyaan human spaceflight missions.
What is SOLVE?
•    SOLVE (Solid Motor-based Sub-Orbital Launch Vehicle for Experiments) is a specialised test vehicle developed by ISRO for conducting Gaganyaan test missions.
•    Its primary purpose is to validate the Integrated Parachute Deceleration System of the Gaganyaan Crew Module under various flight conditions before the actual human mission.
•    The vehicle provides a flexible test platform for simulating different mission conditions and validating the Crew Module's safety systems.
How will SOLVE be used?
•    During SOLVE test missions, the Crew Module will be carried to an altitude of 10–17 km before being separated from the launch vehicle.
•    A series of 10 parachutes will then deploy in sequence to progressively reduce the module's velocity before its safe splashdown in the sea.
•    These tests are intended to verify the reliability of the Crew Module's deceleration and recovery systems under operational conditions.
•    The tests are designed to validate the Crew Module's safe recovery system before astronauts are flown on Gaganyaan missions.
Development of SOLVE
•    The solid stage of SOLVE is derived from the PSLV Strap-on Motor, with modifications to suit Gaganyaan requirements.
•    These modifications include the development of a slow burn-rate propellant, a straight nozzle configuration, and Secondary Injection Thrust Vector Control (SITVC) to meet Gaganyaan test requirements.
•    ISRO reported that the performance parameters during the first ground test were as expected.
SOLVE and the Gaganyaan Mission
•    The Gaganyaan Programme aims to demonstrate India's indigenous human spaceflight capability by launching a three-member crew into a 400 km Low Earth Orbit (LEO).
•    The mission envisages keeping the crew in orbit for three days before safely returning them through splashdown in Indian sea waters.
•    SOLVE forms an important part of this programme by validating one of its most critical safety systems—the safe recovery of astronauts during re-entry.
Recent Developments in Gaganyaan
•    The Gaganyaan programme was originally planned with two uncrewed missions followed by one crewed mission.
•    In October 2024, the programme was expanded from three to eight missions, including an additional uncrewed G1 mission and four precursor missions for the proposed Bharatiya Antariksh Station (BAS).
•    ISRO has also recently conducted the Integrated Air Drop Test (IADT-02) and Mission MITRA (Mapping of Interoperable Traits and Response Assessment), a behavioural study involving the selected Indian astronauts in Leh.
Launch Vehicle
•    The Human Rated LVM3 (HLVM3) has been selected as the launch vehicle for the Gaganyaan mission.
•    It is a human-rated version of ISRO's LVM3 heavy-lift launch vehicle.
•    It consists of a solid stage, a liquid stage and a cryogenic stage.
•    Its systems have been reconfigured to meet the stringent safety requirements necessary for carrying human astronauts into space.