ISRO Gaganyaan G1 Uncrewed Orbital Test Flight

What this countdown tracks

Liftoff of Gaganyaan G1, the first uncrewed orbital test flight of India's human spaceflight programme. The mission will fly a human-rated LVM-3 rocket from Sriharikota carrying a fully instrumented crew module and the half-humanoid Vyommitra. ISRO uses the flight to qualify life-support, re-entry and splashdown systems before any crew boards a Gaganyaan capsule.

Background

ISRO slotted Gaganyaan G1 for December 2026 after a slip from earlier 2024–2025 targets, with Chairman V. Narayanan confirming the revised schedule in press briefings through 2025. The vehicle is the human-rated LVM-3 (HLVM-3), India's heaviest operational launcher at about 640 tonnes lift-off mass, flying from the Second Launch Pad at Satish Dhawan Space Centre, Sriharikota. The 5.3-tonne orbital module pairs a re-entry crew capsule with a service module carrying propellant, solar arrays and life support. Prime Minister Narendra Modi first announced the Gaganyaan programme from the ramparts of the Red Fort on Independence Day 2018, with an original 2022 target subsequently pushed back after COVID-19 disruption and further system-qualification requirements.

Vyommitra, a female-looking humanoid upper-torso robot built at the ISRO Inertial Systems Unit in Thiruvananthapuram, will occupy the commander's seat. She is instrumented to monitor cabin pressure, temperature and acceleration, simulate breathing patterns and exchange voice calls with mission control. The capsule is expected to spend one to three orbits in low Earth orbit at roughly 400 km altitude before a parachute-assisted splashdown in the Bay of Bengal. Two more uncrewed missions — G2 (2027) and TV-D2 — remain on the critical path before crewed flight H1. Four Indian Air Force test pilots — Group Captains Prasanth Balakrishnan Nair, Ajit Krishnan, Angad Pratap and Shubhanshu Shukla — have been named as the astronaut-designate pool and completed initial training in Russia at the Yuri Gagarin Cosmonaut Training Centre before continuing in Bengaluru.

Why the date matters

15 December 2026 is the first credible end-to-end demonstration that India can launch, sustain and safely recover a crewed-class vehicle. A clean G1 flight clears the Crew Escape System and parachute cluster already tested on TV-D1 in October 2023, and unlocks the window for the crewed H1 mission targeted for March 2027. A scrub or anomaly would cascade into the BAS-01 space-station module launch, also riding LVM-3 hardware, slated for 2028. India would become the fourth nation after the Soviet Union/Russia, the United States and China to independently qualify a crewed orbital vehicle, a milestone that the US reached with Mercury-Redstone 3 in 1961 and China with Shenzhou-5 in 2003.

What to watch for

• HLVM-3 lift-off performance, especially S200 booster separation and C25 cryogenic upper-stage burn.
• Orbital module injection parameters and first telemetry contact from Vyommitra.
• Cabin pressure, temperature and radiation data returned during the orbital coast phase.
• Service-module separation timing ahead of re-entry interface at 120 km altitude.
• Parachute sequence — drogues, pilots and three main canopies — and splashdown accuracy.
• INS Nistar and Indian Navy recovery-ship operations in the Bay of Bengal.
• ISRO's post-flight readiness call for G2 and the crewed Gaganyaan H1 mission.
• Performance of the upgraded cryogenic CE-20 engine, now human-rated at 20 tonnes of thrust.
• Communication coverage via ISTRAC ground stations and the IDRSS data-relay satellite.

Flight profile

The planned sequence begins with HLVM-3 ignition at T-0, followed by S200 solid-booster burn through T+140 seconds and separation, L110 liquid-core-stage firing, and C25 cryogenic upper-stage ignition delivering the orbital module to a circular low-Earth orbit. Vyommitra-configured telemetry relays cabin metrics at one-second resolution through ISTRAC stations at Sriharikota, Bengaluru and Port Blair, with coverage gaps filled by the IDRSS-1 relay launched in 2024. Re-entry is planned over the Indian Ocean with a ballistic-skip profile, and the capsule targets a splashdown ellipse roughly 400 km east of Sriharikota. INS Nistar, the navy's first indigenous diving-support vessel, leads the recovery flotilla.

Related events to track

The path from G1 runs directly into Gaganyaan H1 crewed launch in March 2027 and the BAS-01 space-station module in 2028. Cross-region context comes from NASA Dragonfly launch, which shares the late-2028 deep-space cadence.

FAQ

When exactly is Gaganyaan G1? ISRO has publicly targeted December 2026, with 15 December used as the current planning date; the firm launch date will be confirmed nearer the flight readiness review.

Is Gaganyaan G1 confirmed or expected? Confirmed as a mission, with hardware integration underway at Sriharikota; the specific calendar date remains subject to vehicle and weather readiness.

Who is responsible for Gaganyaan G1? The Indian Space Research Organisation, through the Human Space Flight Centre in Bengaluru, with HAL, L&T and Godrej supplying major structural and propulsion elements.

Where can I read the official announcement? ISRO press releases at isro.gov.in and the Department of Space briefings; the mission page on en.wikipedia.org/wiki/Gaganyaan-1 consolidates public statements.