ISRO publishes Gaganyaan crew and service module separation results

ISRO published results on October 16 from integrated tests of the system that separates Gaganyaan's crew capsule from its service module before re-entry. The agency said the ground tests at Vikram Sarabhai Space Centre in Thiruvananthapuram simulated the combined assembly and the severing of electrical and fluid connections between its two modules.

The new account adds an integrated separation test series to the earlier subsystem work described in July. ISRO's July 12 notice had documented a test that detached the crew-side umbilical assembly from a simulated capsule, alongside flotation and apex-cover structural tests. The October announcement covers the separation design of both modules and its effects on capsule equipment.

The two modules operate together from launch through the orbital phase, ISRO explained. Before the capsule returns through Earth's atmosphere, pyrotechnic devices and jettisoning systems must carry out a sequence of separation events. The instrumented ground setup reproduced that sequence, including disconnecting several umbilicals that carry electrical and fluid services.

ISRO said the tests demonstrated the ability of critical capsule subsystems to withstand separation shocks. Its list includes avionics, inertial navigation equipment, thermal protection on the aft and conical heat shields, and a deployable umbilical shield. It also covers pyrotechnic devices belonging to the capsule's uprighting system and its thermal and humidity control system.

The results remain the agency's account of ground testing. The announcement gives no individual test dates or numerical shock measurements, and does not establish that all Gaganyaan flight-readiness work is complete. It retains a 2026 target for the first uncrewed mission, G1, without specifying a launch date.

Update, October 17: This report follows our October 6 Gaganyaan programme-status coverage with the newly published integrated separation-test results. The next flight identified in ISRO's announcement remains the uncrewed G1 mission.