Gaganyaan: Mission milestones achieved by ISRO so far

ISRO successfully tested Cryogenic Upper Stage (CUS) on February 17, 2017

It uses Liquid Oxygen (LOX) and Liquid Hydrogen (LH2) propellant combination

Test of human rated L110-G Vikas Engine accomplished on April 6, 2023

Vikas engine uses storable propellants in a pump-fed gas generator cycle

ISRO completed static test of solid rocket booster (HS200) on May 13, 2022

HS200 rocket booster is the human-rated version of S200 rocket booster of GSLV Mk III

ISRO completed static test of CES motors on August 10, 2022

Crew Escape System takes away the Crew module in case of any eventuality

ISRO completed hot test of Crew Module Propulsion System for re-entry on April 5, 2023

ISRO tested the Service Module Propulsion System on July 19, 2023

It regulated propulsion system that caters to the requirements of the Orbital Module

ISRO completed Integrated Main Parachute Airdrop Test on November 18, 2022

It simulated many cases including when one Main parachute failed to open

ISRO completed the TV D1 Test Flight on October 21, 2023

It tested the Crew Escape System including various separation systems