Gaganyaan mission: Isro's parachute test vehicle clears first ground test
ISRO successfully conducted the first static ground test of the solid motor for SOLVE (Sub-Orbital Launch Vehicle for Experiments), a dedicated test platform developed for validating the Gaganyaan crew module's parachute recovery system.
The solid motor was fired at the Static Test Facility at the Satish Dhawan Space Centre (SDSC), Sriharikota, in a test lasting approximately ten hours.
SOLVE was developed by modifying the solid-fuel strap-on motors used in ISRO's Polar Satellite Launch Vehicle (PSLV), with key changes including a slow-burning propellant formulation and a straight nozzle with secondary injection thrust vector control.
The vehicle is designed to carry a representative crew module to altitudes of 10–17 km, after which a 10-parachute deployment sequence will be triggered to test descent and splashdown recovery.
This ground test precedes integrated air drop tests and eventual full-scale parachute validation flights, which are critical before the first uncrewed Gaganyaan mission (G1) planned for 2026.
Gaganyaan — India's Human Spaceflight Programme
Gaganyaan is ISRO's flagship programme to place a crew of three Indian astronauts into Low Earth Orbit (LEO) at an altitude of ~400 km for a 3-day mission, then return them safely. Approved by the Union Cabinet in December 2018 with an initial budget of ₹10,000 crore, the budget was subsequently enhanced to ₹20,000 crore (Cabinet approval, September 2024). If successful, India will become the fourth country to independently launch humans into orbit, after the United States, Russia, and China.
Key Details
- Launch vehicle: Human Rated LVM3 (LVM3-H), a crewed variant of Launch Vehicle Mark-III
- Crew module re-entry and parachute recovery is designed to end with a sea splashdown in the Bay of Bengal
- Four IAF pilots selected as Gaganauts: Prasanth Balakrishnan Nair, Ajit Krishnan, Angad Pratap, and Shubhanshu Shukla
- Flight sequence: G1 (uncrewed, with Vyommitra humanoid robot) → G2 → G3 → H1 (first crewed flight, targeted Q1 2027)
- ISRO completed over 8,000 cumulative ground tests across subsystems by 2026
SOLVE is a purpose-built test rocket to validate the 10-parachute recovery system that will bring the Gaganyaan crew module safely back to Earth; this ground test is the foundational step before integrated in-flight parachute trials.
Parachute Recovery Systems in Crewed Spaceflight
A parachute recovery system (also called a recovery parachute system or RPS) is the final deceleration mechanism used to bring a crewed capsule from high-speed atmospheric re-entry to a safe touchdown or splashdown speed. Systems typically use a staged deployment: drogue chutes deploy first at higher altitudes to stabilize and slow the capsule, followed by larger main parachutes that further reduce terminal velocity to safe levels (typically 5–10 m/s at touchdown).
Key Details
- Gaganyaan's 10-parachute system includes: 2 apex cover separation parachutes (Ø 2.5 m), 2 drogue parachutes (Ø 5.8 m), 3 pilot parachutes (Ø 3.4 m), and 3 main parachutes (Ø 25 m)
- ISRO also conducted Integrated Air Drop Tests (IADT) using IAF Chinook helicopters dropping a 4.8-tonne crew module mock-up from ~3 km over the Bay of Bengal — the second IADT was completed on 10 April 2026
- The parachute system must handle both nominal re-entry and abort scenarios (e.g., Crew Escape System activation at low altitude)
The SOLVE solid motor test is the precursor to high-altitude parachute deployment tests that cannot be validated cheaply with a full LVM3; SOLVE provides a cost-effective, dedicated test environment.
Sub-Orbital Launch Vehicles — Role in Space Technology Development
A sub-orbital vehicle reaches space or the upper atmosphere but does not achieve the orbital velocity (approximately 7.9 km/s) needed to circle Earth. Such vehicles are used for microgravity experiments, atmospheric research, and, critically, for testing re-entry and recovery technologies at realistic altitudes and velocities without the cost of an orbital launch. ISRO previously used a Test Vehicle (TV-D1) to test the Crew Escape System in October 2023; SOLVE extends this test-flight philosophy to parachute systems.
Key Details
- SOLVE is derived from PSLV strap-on solid motors (PS2S / PSOM class), modified with a slow-burn propellant and secondary injection thrust vector control
- Target test altitude: 10–17 km — sufficient to replicate drogue and main chute deployment conditions
- The approach mirrors NASA's use of the Pad Abort Test and Liberty Bell abort test vehicles, and Russia's use of specialized recovery test rockets for Soyuz
By successfully firing SOLVE's solid motor at Sriharikota, ISRO validated the propulsion element of this dedicated test platform, clearing the way for full-scale integrated parachute drop tests.
- SOLVE full form: Sub-Orbital Launch Vehicle for Experiments
- Gaganyaan budget: ₹10,000 crore (2018 approval); enhanced to ₹20,000 crore (September 2024 Cabinet approval)
- Target orbit: ~400 km LEO; mission duration: 3 days
- Number of parachutes in Gaganyaan recovery system: 10 (staged deployment)
- Main parachutes diameter: 25 m each (3 units)
- SOLVE test altitude range: 10–17 km
- Test facility: Static Test Facility, Satish Dhawan Space Centre, Sriharikota, Andhra Pradesh
- India would be the 4th country to independently achieve human orbital spaceflight (after USA, Russia, China)
- First crewed mission (H1) targeted: Q1 2027
- Four Gaganauts selected, all IAF pilots
- Second Integrated Air Drop Test completed: 10 April 2026