The Human Spaceflight Programme (HSP) aims to undertake a mission to carry crew of two to LEO and return them safely to a predefined destination on Earth.
The mission will have the following features.
Mission duration is a few hours for the first mission extendable up to seven days
Emergency mission abort and crew escape provision is provided during launch pad, ascent and orbital phases of flight
Crew module has capability to manoeuvre in atmosphere up to a down range of +/- 125 km and cross range of +/- 60 km
Throughout the mission acceleration is within 4 g
Figure 1: Indian Human spaceflight - Orbital Vehicle
India plans to undertake a human spaceflight programme during the second half of this decade. The configuration selected for the first flight is one with a base diameter of 3.1 m and 14o boat tail angle as shown in Figure 1. The first flight will be for a few low earth orbits.
The entire mission design is done with crew safety as the prime factor under consideration. There is a viable crew escape provision during the entire launch vehicle ascent mission regime. During the initial phase this is achieved by means of a crew escape system (Figure 2) and later utilising the service module propulsion systems.
Figure 2: Crew Escape System Schematic
The first human spaceflight mission will be followed by longer duration missions, which will include EVA (Extra Vehicular Activity), microgravity experiments with human intervention and monitoring etc. A separate habitat module will be appended and extended missions lasting a month or more will be attempted. Further, human space missions to Moon and Mars are also under study.
Technologies for human spaceflight
Various new and complex technologies are to be developed for the human spaceflight programme. Some of the important ones are listed below.
Crew module systems: Crew Module is the control centre and living quarters of the crew for the entire mission. It has all the sub-systems required to ensure safe and comfortable environment for crew and for mission management.
Crew escape system: Crew escape system ensures safety of crew in case of exigencies. It consists of an Abort Sensing and Implementation System (ASIS) and fast acting solid motors which quickly and automatically removes Crew Module to a safe location in case of an emergency under any impending failures.
Environment control and life support system (ECLSS): ECLSS ensures comfortable environment inside crew cabin by effectively controlling pressure, temperature and humidity. It also caters to the human need for water, air, food and management of waste.
Flight suit: The flight suit is a pressure retention structure. This protects crew under emergencies like an ECLSS failure. It provides all the basic necessities for life support such as breathable oxygen, required pressure, temperature regulation, carbon dioxide removal, clear vision, mobility, communication system, and collection of body wastes.
Mission management with human in the loop: The entire mission design is to be carried out with crew safety as the prime factor. Using human onboard for effective mission management is different from the autonomous missions of normal launch vehicles and satellites.
Redundant navigation, guidance and control system: As part of human rating, the launch vehicle and orbital vehicle avionics should be strengthened to achieve very high reliability with adequate fault tolerance. This calls for better redundancy and fault detection and isolation capability in navigation, guidance and control system, than existing. Quad redundant NGC system for Crew module and TMR for launch vehicle are proposed.
Human-rating of launch vehicle and systems: For human rating of launch vehicle, all flight systems will have to be verified and re-designed, if necessary, to ensure that no two failures shall result in permanent disability or loss of crew life. Features like increased safety margins, added redundancy and increased safety and reliability will be addressed exhaustively.
Simulators for verification, validation and crew training: Numerous static and dynamic simulators are essential for the programme. This includes simulators for qualifying subsystems like avionics, life support systems etc. and simulators for training the crew to get them familiarised with operations during nominal and off-nominal mission scenarios.
Crew health monitoring systems/bio-astronautics: Monitoring health of the crew during mission requires development of sensors, electronics and telemetry. There is a need for initiating studies on Bio-astronautics.
Space medicine: Space medicine is another important area which has to address various discomforts and medical emergencies during space missions along with the needed remedial actions. For sustained long duration space missions, fundamental research on space medicine is essential.
Crew training and required facilities: Crew-training programme should provide astronauts and ground personnel with appropriate knowledge, skills and aptitude required for space missions, on-orbit operations, safety and mission success.
Technologies for deep space missions: For deep space missions lasting months, many new technologies have to be mastered like integrated vehicle health monitoring, advanced propulsion systems, advanced automated rendezvous and capture, robotics, regenerative life support system, extraterrestrial mining, surface habitation, healthcare at remote location and radiation protection systems.
India’s aspirations
India’s space journey started in 1963 with upper atmospheric studies using sounding rockets. After more than four decades, India has a big constellation of government-owned communication and remote sensing satellites serving the country in several application programmes. The launch vehicle services have fully matured to meet the national demands.
Undertaking a human spaceflight in the coming years is an idea that is gaining momentum in the country and is being debated actively. ISRO has carried out detailed studies to assess the feasibility of putting a human in orbit and bringing him/her back safely to a specified destination on earth.
It is always argued that for a country like India, priority should be for poverty eradication, providing drinking water to masses etc. While these sectors should get the needed priority, it is essential to undertake the developments in advanced technologies parallely. The same question was raised 40 years back about our space programme but today the benefits derived from the Indian space programme have far exceeded the initial expectations and has immensely contributed to improve the quality of life of the common man.
As nations and their partners return to moon, ventures to Mars and to points between and beyond, human spaceflight will succeed as it embodies the human quest for exploration and it is one mission that India is bent on making it possible.