The Indian Space Research Organisation (ISRO) successfully conducted the first static ground test of the solid motor for the Sub-Orbital Launch Vehicle for Experiments (SOLVE) on 3 July 2026 at the Static Test Facility of the Satish Dhawan Space Centre (SDSC), Sriharikota. The successful test marks a major milestone in validating the crew safety systems of India's Gaganyaan Human Spaceflight Mission.

What is SOLVE?

SOLVE (Sub-Orbital Launch Vehicle for Experiments) is a dedicated, cost-effective sub-orbital launch vehicle developed by ISRO to conduct Integrated Parachute Tests (IPT) for the Gaganyaan Crew Module.

Its primary objective is to validate the parachute-based deceleration and recovery system of the crew module under realistic high-altitude atmospheric conditions before the actual human spaceflight mission.

Key Features of SOLVE

1. Dedicated Test Vehicle

• Designed exclusively for Integrated Parachute Tests (IPT).
• Provides a realistic environment for testing astronaut recovery systems.

2. PSLV-Based Solid Motor

• Uses a solid rocket motor derived from the Polar Satellite Launch Vehicle (PSLV) Strap-on Booster.
• Modified specifically to meet Gaganyaan mission requirements.

3. Indigenous Technological Improvements

ISRO introduced several modifications, including:

• Slow burn-rate solid propellant.
• Straight nozzle configuration.
• Secondary Injection Thrust Vector Control (SITVC) system for improved flight control.

4. Flight Profile

• During future missions, SOLVE will carry the Gaganyaan Crew Module to an altitude of 10–17 km.

5. Parachute Recovery Sequence

After reaching the designated altitude:

• The crew module separates from the launch vehicle.
• A carefully designed sequence of 10 parachutes is deployed.
• The module slows down safely before making a controlled splashdown in the sea.

Significance for the Gaganyaan Mission

The safe return of astronauts is considered the most critical phase of any human spaceflight mission.

Earlier, ISRO validated the parachute system through:

• Integrated Air Drop Tests (IADT) using helicopters from approximately 3 km altitude.

However, SOLVE enables:

• Testing at much higher altitudes (10–17 km).
• Validation under higher-speed sub-orbital conditions.
• Comprehensive testing of the complete 10-parachute recovery system.

Thus, SOLVE significantly enhances the reliability and safety of the Gaganyaan mission.

Outcome of the Ground Test

According to ISRO:

• All motor performance parameters matched the expected values.
• The successful static firing has cleared the way for a series of uncrewed demonstration flights before India's first crewed Gaganyaan mission.

About Gaganyaan Mission

• Agency: Indian Space Research Organisation (ISRO)
• Objective: To demonstrate India's capability to send humans into Low Earth Orbit (LEO) and safely bring them back.
• Mission Type: India's first indigenous human spaceflight mission.
• Crew: Three astronauts.
• Orbit: Approximately 400 km Low Earth Orbit (LEO).
• Mission Duration: Around 3 days.
• Launch Vehicle: Human-rated LVM3 (Launch Vehicle Mark-3).
• Landing: Controlled splashdown in the Bay of Bengal using a multi-stage parachute recovery system.

About ISRO

• Established: 15 August 1969
• Founder: Dr. Vikram Sarabhai
• Headquarters: Bengaluru, Karnataka
• Chairman: V. Narayanan
• Major Missions:

• • Aryabhata (1975)
  • Rohini (1980)
  • Chandrayaan-1 (2008)
  • Mars Orbiter Mission (2013)
  • Chandrayaan-2 (2019)
  • Chandrayaan-3 (2023)
  • Aditya-L1 (2023)