New Delhi: The Indian Space Research Organisation (ISRO) has successfully completed the first static ground test of the solid motor for its newly developed Sub-Orbital Launch Vehicle for Experiments (SOLVE), achieving another significant milestone in India’s ambitious Gaganyaan human spaceflight programme. The successful test strengthens ISRO’s preparations for the country’s maiden crewed space mission, which aims to send Indian astronauts into low-Earth orbit.

The ground test was conducted on July 3 at the Static Test Facility of the Satish Dhawan Space Centre (SDSC-SHAR), Sriharikota, where the motor performed as expected, validating its design and operational parameters.

ISRO conducts ground test for new sub-orbital solid motor-based test vehicle, Sub-Orbital Launch Vehicle for Experiments (SOLVE)https://t.co/zJRkNzZRWT pic.twitter.com/WTBCYy3fHB

— r_isro (@r_isro) July 4, 2026

SOLVE to Validate Gaganyaan’s Critical Parachute System

ISRO has developed SOLVE (Sub-Orbital Launch Vehicle for Experiments) as a dedicated test platform to conduct integrated parachute tests for the Gaganyaan Crew Module under varying mission conditions.

During future experimental flights, SOLVE will carry the Crew Module to an altitude of 10–17 kilometres, where it will separate from the launch vehicle. The module will then deploy a sequence of 10 parachutes to gradually slow its descent before making a controlled splashdown in the sea—a crucial safety requirement for India’s first human spaceflight mission.

Modified PSLV Technology

The solid stage of SOLVE has been adapted from the Polar Satellite Launch Vehicle (PSLV) strap-on motor. However, ISRO engineers introduced several modifications to meet the stringent safety and performance requirements of human spaceflight.

These include:

• Development of a slow-burn solid propellant
• Integration of a straight nozzle
• Addition of Secondary Injection Thrust Vector Control (SITVC) for improved flight stability and control

According to ISRO, the successful motor test confirms that these modifications are functioning as intended and will provide greater flexibility in conducting various Gaganyaan test missions.

Vital Step Towards India’s First Crewed Mission

The Gaganyaan mission will mark India’s first indigenous human spaceflight, with plans to send a crew of two to three astronauts into a 400-kilometre low-Earth orbit for a mission lasting about three days, followed by a safe return and splashdown in Indian waters.

Before astronauts are launched, ISRO is carrying out an extensive series of qualification tests covering launch systems, crew escape technologies, propulsion, parachute recovery and spacecraft safety. The SOLVE platform is expected to play a key role in validating one of the mission’s most critical components—the Crew Module’s deceleration and recovery system.

The successful SOLVE motor test adds to a series of recent Gaganyaan-related milestones and keeps ISRO on track as it prepares for upcoming uncrewed demonstration flights before India’s historic first human space mission.