How the Gaganyaan crew module is built to survive

Gaganyaan is India’s maiden crewed space mission, designed to carry Indian astronauts to space and safely return them back to earth. Human-rated Launch Vehicle Mark (HLVM) 3 will inject the orbital module (OM) into the desired orbit. The Gaganyaan astronauts will be onboard the OM.

What does the OM contain?

• The Orbital Module (OM) consists of two sections:
  • ○    Crew Module (CM)
  • ○    Service Module (SM)
• Both modules are connected through a joint.
• The Crew Module serves as the living space or habitat for astronauts.
• The Service Module provides propulsion and other on-orbit support.
• After the orbital phase, the Service Module’s thrusters de-orbit the OM.
• The Service Module then separates from the Crew Module through a redundant separation mechanism.
• During re-entry:
  • The Crew Module withstands intense thermal and structural loads.
  • It decelerates through aero-braking and safely splashes down in the sea.
  • The Service Module burns up in the atmosphere.
• Spacecraft such as Russia’s Soyuz and China’s Shenzhou use a three-module configuration.
• Their third module provides additional living and working space, docking facilities, cargo storage and basic life-support facilities, including a toilet. 
• This third module also separates and burns up during re-entry.

Which configuration is best for re-entry?

• Crew module design balances volume, mass, stability, lift and thermal protection.
• A sphere offers maximum volume with minimum structural mass.
• However, a sphere produces no lift and causes high g-forces.
• A sphere-cone configuration provides heat protection, stability and controlled descent.
• Gaganyaan uses the sphere-cone configuration.

Why aren’t all re-entry modules mono-stable?

• Mono-stability keeps the module in one stable orientation during atmospheric flight and after splashdown.
• It depends on aerodynamic shape and the location of the centre of gravity.
• Internal subsystem placement often prevents engineers from positioning the centre of gravity ideally.
• Therefore, re-entry modules may have multiple stable aerodynamic and hydrodynamic orientations.
• Gaganyaan uses control thrusters in flight and a gas-based up-righting system after splashdown.

What is dynamic instability during re-entry?

• Dynamic instability causes rapidly increasing and uncontrolled oscillations during atmospheric descent.
• It depends on the module’s shape, mass and surrounding airflow.
• Instability is greatest near the speed of sound due to shockwaves and turbulent airflow.
• Uncontrolled oscillations can make the crew module tumble dangerously.
• Control thrusters or early parachute deployment are used to stabilise the module.

(MeitY) and Drone Federation India launch National Innovation Challenge for Drone Research (NIDAR) under SwaYaan initiative-PIB 
The Ministry of Electronics and Information Technology (MeitY), in collaboration with the Drone Federation India (DFI), launched the National Innovation Challenge for Drone Application and Research (NIDAR) under the ‘SwaYaan - Capacity Building for Human Resource Development in Unmanned Aircraft Systems’ initiative. 

About SwaYaan

• SwaYaan is a MeitY initiative approved in July 2022 for capacity building in drones and allied UAS technologies.
• It aims to train 42,560 participants through formal and non-formal education programmes.
• The initiative follows a hub-and-spoke model involving 30 institutions, including IISc, IITs, IIITs, NITs, CDAC and NIELIT.
• Its five focus areas are Drone Electronics, GNC Algorithms and Simulation, Aeromechanics, Drone Applications and Allied UAS Technologies.
• More than 14,000 beneficiaries have been trained so far.
• IIT Kanpur has launched an M.Tech. programme in UAS Engineering under the initiative.
• Several minor degree programmes, bootcamps and workshops have also been introduced.
• Industry participation is promoted through innovation challenges and industry meets.