Mission Gaganyaan India's Biggest Space Challenge
FEATURE ARTICLE Mission Gaganyaan India’s Biggest Space Challenge Anand Kumar Sharma
HE Indian Space Research Organisation (ISRO) is escape system, thermal protection, deceleration and flotation expanding its wings to one more vertical – indigenous systems and re-entry capability. The total programme cost of T Human Spaceflight Programme. On 2 April 1984, Gaganyaan is now expected to be within Rs 10,000 crores. Rakesh Sharma an Indian Air Force pilot flew aboard Soyuz The cost includes technology development, flight hardware T-11, launched, as part of the Interkosmos programme. realization and essential infrastructure establishment. Now, ISRO is working on an Indian crewed orbital mission – Gaganyaan – that would take Indian astronauts to space by 2022. Human Space Flight Centre (HSFC) India could potentially become the fourth country to send ISRO created a Human Space Flight Centre (HSFC) on 30 a man in space, after the erstwhile USSR, the US and China. January 2019 at the ISRO Headquarter campus in Bengaluru. Denmark also has a manned space flight scheduled for 2022. The responsibilities of the HSFC include end-to-end mission ISRO is therefore giving the topmost priority to Ganganyaan planning, development of engineering systems for crew survival Mission and looking for all possibilities of launch by December in space, crew selection and training and also pursuing activities 2021. for sustained human space flight missions. The HSFC will function as a nodal agency with the Gaganyaan Objectives existing ISRO centres support the implementation and testing Gaganyaan will be the first Indian crewed orbital spacecraft of spacecraft. under the Human Space Flight programme of ISRO. It is scheduled to be launched with the powerful GSLV Mk III rocket Gaganyaan Orbiter by 2022 to commemorate the 75th year of India’s Independence. In the Gaganyaan composite capsule, the crew module is mated Gaganyaan consists of a service module and a crew to the service module, and together they are called the orbital module, collectively known as the orbital capsule. The current craft. The craft will be equipped with emergency mission abort plan is to have two unmanned and one manned flight under and emergency escape system that can be exercised at the first Gaganyaan Programme. The first un-crewed flight is planned stage or second stage of the rocket burn. In future crewed flights in December 2020 and second in July 2021. Following two of ISRO, an upgraded version of the spacecraft with rendezvous successful unmanned flights, first crewed mission is scheduled and docking capabilities is also envisaged. in December 2021. The launch mass of Gaganyaan composite orbiter will Spacecraft carrying people may be operated by human be approximately 7800 kg (3,735 kg dry mass). The craft is crew, or remotely operated from ground stations or may planned to be built as double walled with six outer panels in be autonomous. The Gaganyaan is a largely autonomous semi-cylindrical shape. Double wall is used to thermally isolate spacecraft. The crewed spacecraft is intended to orbit in the the craft from varying external heat loads. The crew module low Earth orbit for 5-7 days and then bring back the crew with capacity to carry 2-3 astronauts and a volume of about module safely. 8 m3 will have controlled cabin environment. During the The main objective of the Gaganyaan mission is mission, crew will carry out a microgravity experiment. technology demonstration. The programme will source 60-70% Service module decks are populated with various components and value-added services from Indian industries. housekeeping elements and propulsion tanks. It will also house During the early years of planning, the cost was estimated at the instruments for servicing of the crew module like life about Rs 12,400 crore. support and environmental control system. ISRO has already developed and demonstrated many The service module will be powered by two bipropellant critical technologies like crew module configuration, crew liquid propellant engines. The craft will be powered by two
20 | Science Reporter | January 2020 GAGANYAAN : SYSTEMS
Crew Module
Orbital Module
Service Module
Gaganyaan composite capsule
MANNED MISSION
Solar array 5-7 Re-orientation (module changes direction) deployment days in space De-boost Orbit module Separation of crew and SPACE service modules
EARTH’S ATMOSPHERE Aerobraking
16 min Parachute deployment to reach Splashdown off 36 mins low-earth Gujarat from orbit Re-entry de-boost De-boost to landing
GSLV MK III lift off from Orbit module Splashdown at Sriharikota Descent trajectory separation Ascent trajectory Arabian sea off Gujarat
Crew module recovery in 15-20 minutes
COST: Less than LAUNCH: India to be the fourth nation to launch 10,000cr 2022 a manned spaceflight mission after the US, Russia and China
Gaganyaan space voyage and crew module recovery plan
January 2020 | Science Reporter | 21 Environmental hazards: Space environment is hostile. There is lack of gravity and atmosphere and danger of radiation. Astronauts may have medical issues with the hostile space environment.
Microgravity: Transition from one gravity field to another affects hand-eye and head-eye coordination. In microgravity astronauts often lose their orientation, vision, muscle strength, aerobic capacity and bone density. In absence of gravity, bones lose minerals, hence the astronauts are at greater risk of osteoporosis-related fractures. Astronauts can lose up to twenty per cent of their muscle mass on spaceflights lasting five to eleven days. The consequent loss of strength could be a serious problem in case of a landing emergency. Astronauts have to exercise and maintain strict diet to remain healthy. The human blood starts boiling if there is no pressure; hence inside the crew acceptable atmospheric pressure has to be maintained.
Radiation exposure: Though the radiation exposure is not of Deployment of CARE parachutes much consequence to Gaganyaan, it has relevance to our future human space flight programme. In space stations, astronauts receive over ten times higher radiation than what people are photovoltaic solar arrays, which are stowed in the launch subjected on the Earth. Radiation exposure may increase the configuration and are deployed after injection. Solar array with risk of cancer. It can damage the central nervous system and power generation capacity of 5-6 KW coupled with lithium ion weaken the immune system. Radiation can also cause nausea, batteries will provide the required power support. vomiting, anorexia and fatigue. Beyond low Earth orbit, the About 16 minutes after lift-off from the Satish Dhawan crew might be at risk from high-energy protons emitted by Space Centre (SDSC), Sriharikota, the rocket will inject the solar flares that may cause radiation sickness and even death. spacecraft into an orbit, 300-400 km above the Earth. The capsule will rotate around the Earth every 90 minutes and Isolation: No matter how well astronauts are trained, astronauts will be able to witness sunrise and sunset. The behavioural issues are likely to crop up when astronauts are astronauts will be able to see India from space every 24 hours. confined into small spaces and have to rely on limited resources. The capsule is planned to orbit 5-7 days in space and Astronauts may encounter depression, cabin fever, fatigue, return. It will take about 36 hours for return and landing. When sleep disorder and other psychiatric disorders. the capsule is ready to land, the parachutes will be deployed for splashdown in the Bay of Bengal. Crew module is equipped Sensory systems: During spaceflight astronauts are in extreme with two parachutes for redundancy, while only one parachute environment state that may result in the weakening of their is good enough for safe splashdown. The parachutes would senses: hearing, sight, smell, taste, touch, vestibular (motion reduce the speed of the crew module from over 216 m/s to and equilibrium system) and proprioception system (sense under 11 m/s at splashdown. of the relative position of one’s own parts of the body). The mental health of astronauts may be affected by the changes in Challenges for Gaganyaan the sensory systems during space travel. The Gaganyaan mission is so challenging because for the first time humans will be launched into space and must be brought Physiological and metabolic requirements: All the things back safely. Making a crew module where the astronauts can necessary for supporting physiological need of astronauts, like live in Earth-like conditions in space and bring the spacecraft food, water, medicine, and human waste removal have to be back to Earth after the flight are challenging. addressed. An astronaut requires approximately 5 kilograms All the elements and sub-systems planned to be used in of oxygen, food and water (oxygen, 0.84 kg; food, 0.62 kg; Gaganyaan require very careful verification and validation for and water, 3.54 kg) per day to perform the standard activities. human rating. ISRO is adopting a philosophy of quadruple An output as waste in similar range is expected (solid wastes, redundancy for the major active systems of Gaganyaan mission. 0.11 kg; liquid wastes, 3.89 kg and carbon dioxide, 1.00 kg). Redundancy is the multiplication of critical components or These levels can vary with the activity level of a specific functions of a system with the intention of increasing reliability mission, but the rule of basic mass balance will follow. of the system. Multiple redundancy of a system makes it very In addition to drinking, water is also consumed by the complex and the system reliability has to be very carefully crew for showering and washing activities. Hence, the actual examined. water use during the mission may typically be double of the In spite of utmost care, there are always formidable risks given value. Water must be stored, used economically and involved, such as:
22 | Science Reporter | January 2020 reclaimed from waste. All human space missions so far have used in space suits for extravehicular activity, where acceptable used specific supplied food for astronauts. A composite waste suit flexibility mandates the lowest inflation pressure. Use of management system has to be designed to minimise and store nitrogen/oxygen atmosphere before launch, and low-pressure the waste efficiently. pure oxygen only in space is considered a safer option. While the layout and design of the ECLSS have been Life Support System: In human spaceflight, an Environmental finalised, its many individual components and systems are in Control and Life Support System (ECLSS) supplies the the process of being tested. The design and configuration of essentials, maintains the acceptable environment and deals with the inside of the crew module have also been finalised. Ground the management of waste products. Shielding against harmful testing will have to be followed by tests in the space orbit while external influences such as radiation and micro-meteorites is simulating zero gravity and deep vacuum. also ensured. The ECLSS maintains a steady cabin pressure and air composition, removes carbon dioxide and other harmful Aerospace Technology Challenges gases, controls temperature and humidity and also manage the Launch Escape System: Space flight requires much higher other important parameters like fire detection and suppression, velocities than air transportation, which in turn requires high food and water management and emergency support. energy density propellants. This results in dissipation of large amounts of energy to pass through the Earth’s atmosphere. Artificial atmosphere: There are two basic choices for an Travelling in a rocket is like sitting on an exploding bomb which artificial atmosphere, either an Earth-like mixture of oxygen will push your speed from 0 to over 25,000 km per hour in in an inert gas such as nitrogen or helium or argon, or pure few minutes. Anything may go wrong during the pre-launch, oxygen. launch and post-phase, including the explosion of rocket into a A pure or concentrated oxygen atmosphere is toxic and has fireball. Launch escape system safety features have to be built fire risk, especially in ground operations when for structural to minimize the loss. reasons the total cabin pressure must exceed the external A Crew Escape System is therefore a crucial escape safety atmospheric pressure. The concentrated oxygen can, however, technology for astronauts in an emergency/faulty mission be used at lower atmospheric pressure. By reducing or omitting situation. It ensures an advance warning of anything abnormal diluents (constituents other than oxygen, e.g., nitrogen, helium to the crew module and pulls it away to a safe distance. From and argon) the total pressure can be lowered to a minimum of there it can be landed either on sea or on land with the help of about 16 kPa. This can lighten spacecraft structures, reduce attached parachutes. Ejection seats carry astronauts out of the leaks and simplify the life support system. capsule and away for individual parachute landing. A conventional nitrogen-oxygen air is used in the most ISRO successfully conducted a Pad Abort Test on 5 July modern crewed spacecraft (e.g., International Space Station, 2018 to determine how well the system could get the crew of Soyuz spacecraft). The low-pressure pure oxygen is commonly a spacecraft to safety in an emergency on the launch pad. It is similar to an ejection seat for a fighter pilot, but instead of ejecting the pilot out of the spacecraft, the entire spacecraft is “ejected” away from the launch vehicle.
Re-entry and recovery: Normal satellites launched for communication, remote sensing or scientific applications remain in space, even when their life is over. Any human space flight, however, has to come back safely to Earth. This involves mastering of the highly complicated re-entry and recovery technology. When a spacecraft re-enters Earth’s atmosphere, it would have to withstand high temperatures of thousands of degrees, due to friction with the air. This friction increases the temperature so much that most of the meteorites just vaporise before reaching the Earth. Further, the spacecraft’s re-entry into the atmosphere has to be very precise following a pre-planned trajectory in terms of speed and angle. Even the slightest deviation could end into a disaster. For this, a heat shield that can withstand the temperature of thousands of degrees needs to be developed. After re-entry, the capsule should land at a designated spot in the sea from where Navy or Coast Guard would bring it back to the mainland. Re-entry of the human spaceflight into Earth’s atmosphere is a very complex technology. There are few examples of re-entry disasters. Crew Module Atmospheric Re-entry Experiment (CARE) was an experimental test vehicle for Gaganyaan. It was launched Space suits developed by ISRO for Indian astronauts
January 2020 | Science Reporter | 23 by GSLV Mk III on 18 December 2014 to an altitude of 126 of the mission, the science experiments will be taken up in km from the Second Launch Pad of the Satish Dhawan Space collaboration with other organisations. Centre, Sriharikota. The selection process is being conducted in three phases. After about 20 minutes of lift-off, the CARE module re- The first phase selection started with 100 candidates who were entered, deployed its parachutes as planned and splashed down identified based on certain quality requirements. The selection into the Bay of Bengal. The crew module was recovered by process was based on volunteers as well as those who were the Indian Coast Guard from the Bay of Bengal about 600 km selected from amongst the flight engineers, pilots, fighter pilots from Port Blair in the Andaman Islands and about 1600 km and experienced Indian Air Force test pilots. from the Sriharikota launch site. In the next phase, ten selected Vyomnauts had to go through rigorous testing that included gruelling physical exercises, lab Space suit: ISRO had displayed the Gaganyaan crew model and investigations, radiological tests, clinical tests and evaluation on orange space suits at the Bengaluru Space Expo (BSX-2018) various facets of their psychology. At the end of the rigorous during September 6 to 8, 2018. The space suits were designed training at the Institute of Aerospace Medicine out of the 10 at the Vikram Sarabhai Space Centre, Thiruvananthapuram. shortlisted Vyomnauts only six may be sent for advance training Space Suits for Indian astronauts will be built by DEBEL/ to Roscosmos that includes a short module of training onboard DRDO at Bengaluru. a Soyuz spacecraft. And finally, only 2-3 Vyomnauts will be The orange colour is preferred as it is the most visible chosen to participate in the first Indian manned space mission. colour during search and rescue, if something goes wrong during lift off and landing. The helmet is made from The Rocket – GSLV MkIII polycarbonate to provide protection from tiny micrometeorites. One of the most important requirements is the development of An inner clear plastic bubble contains pressurised oxygen that a launch vehicle that can carry heavy payloads into space. The the astronaut breathes. If they get thirsty, they can bite down Gaganyaan composite module is likely to weigh ~7.8 tonnes. on a small tube and suck liquid kept in a bag attached to the ISRO’s main launch vehicle, the PSLV (Polar Satellite Launch inside of the torso segment. Vehicle), which carried the Chandrayaan and Mangalyaan To keep contact with other astronauts and mission control missions too, can carry payloads that are barely up to 2 on Earth, a headpiece colloquially referred to as the “snoopy tonnes, and that too only to orbits at about 600 km altitude cap” containing a microphone and headset is placed inside from the Earth’s surface. After focused efforts on developing the helmet. an indigenous cryogenic engine to power the rocket, ISRO The upper torso is made of fibreglass and the life support successfully tested GSLV MkIII to deliver heavier payloads system is attached to the rear of the suit like a backpack. much deeper into space. Lithium hydroxide canisters pull carbon dioxide from the air GSLV Mk III, which is also referred as the Launch as the astronaut breathes. This is similar to the rebreathers Vehicle Mark 3, LVM 3 or GSLV III, will be used to launch used by the scuba divers. Oxygen tanks refresh the circulating Gaganyaan. GSLV Mk III is designed to carry 4-ton class of pure oxygen air. satellites into Geosynchronous Transfer Orbit (GTO) or about The inner layers of the spacesuit have pipes running down 10 tons to Low Earth Orbit (LEO), which is about twice the the astronaut’s arms and legs for liquid cooling and ventilation. capability of the GSLV Mk II. Cooling water supplied by the life support system keeps heat in GSLV Mk III is a three-stage heavy lift launch vehicle check and sweat is absorbed to prevent condensation. developed by ISRO. The vehicle has two solid strap-ons, a core liquid booster and a cryogenic upper stage. The two strap-on Astronaut Training motors of GSLV Mk III are located on either side of its core The Indian astronauts will be addressed as “Vyomnauts”. liquid booster. Designated as ‘S200’, each carries 205 tons of ISRO’s Human Space Flight Centre and Glavcosmos, which composite solid propellant and their ignition results in vehicle is a subsidiary of the Russian state corporation Roscosmos, lift-off. Strap-on function for 140 seconds. signed an agreement on 1 July 2019 for cooperation in the During the strap-on functioning phase, the two clustered selection, support, medical examination and space training of Vikas liquid Engines of L110 liquid core booster will ignite Indian astronauts. An ISRO Technical Liaison Unit (ITLU) 114 seconds after lift-off to further augment the thrust of is setup in Moscow to facilitate the development of some key the vehicle. These two engines continue to function after the technologies and establishment of special facilities which are separation of the strap-onsat about 140 seconds after lift-off. essential to support life in space. The Gaganyaan Mission target of 2022 will mark the ISRO has signed an MoU with the Indian Air Force (IAF) culmination of nearly 15 years of background efforts of ISRO. for crew management activities. The scope of MoU includes The country eagerly awaits the successful launch of India’s first co-operation in crew screening and selection, crew health human spaceflight by 2022. management, post travel rehabilitation, etc. The IAF in consultation with ISRO prepared an extensive Dr Anand Kumar Sharma ([email protected]) superannuated road map for the selection and training of the future Vyomnauts from ISRO as Distinguished Scientist on 31 August 2019. At ISRO, for the Gaganyaan mission. The crew will be selected by he was involved in the design, testing and realisation of Thermal IAF and ISRO jointly after which they will undergo training. Control/Mechanical Systems of Spacecraft. His research focused on While ISRO will be focussing on the engineering aspects the development of thermal control coatings for space applications.
24 | Science Reporter | January 2020