Friday, November 29, 2019
Commercial Crew The Return of Manned Missions
Commercial Crew The Return of Manned Missions Commercial Crew The Return of Manned Missions Commercial Crew The Return of Manned MissionsIn First Man, the 2018 film depicting human spaceflight in the 1960s, we see astronaut Neil Armstrong and his co-pilot David Scott onboard Gemini VIII executing the worlds first docking with another space vehicle, Agena. Shortly after docking, one of Geminis thrusters malfunctions. The crew undocks from the space vehicle, but the spacecraft goes into dangerously wildbret gyrations, forcing the astronauts to deploy the re-entry control ordnungsprinzip to stop and make an emergency landing in the Pacific.The film takes us through a series of accidents, including the Apollo 1 fire, that highlight what it took at that time to become a NASA astronaut. Those incidents, however, didnt deter the agencys efforts to turn the human spaceflight dream into a reality. Ultimately, Armstrong was chosen to lead the legendary space mission that made him the first man to walk on the Moon on July 20, 1969.The United States sent men to the Moon five decades ago. Now, we cant even send astronauts to low-Earth bahnorbit.The Space Shuttle program that ferried American astronauts to space began in 1981 and was retired in 2011 as it didnt meet its promise for low-cost access to space. STS-135, the final flight of Atlantis and the shuttle program, touched down at Kennedy Space Center on July 21, 2011. Since then, NASA has relied on the Russian Soyuz spacecraft to take its astronauts to the Interlandal Space Station (ISS). The agency last purchased Soyuz seats for $75 million apiece in 2017.However, if all goes to plan this could change by the end of the year, as two private companies working with NASA prepare to meet its goal of launching the first astronauts into orbit from the U.S. soil since the end of the shuttle program.This new model of parteicipation where government and private partnerships are put in distributionspolitik is really an extension of innovation in contracting and the business of space, the engineering, and technology, said John M. Horack, who holds the Neil A. Armstrong Chair, a joint appointment in the College of Engineering and the John Glenn College of Public Affairs at the Ohio State University in Columbus. We have found new and successful ways of engagement between private and public sectors so that we can develop an entire new fleet of launch vehicles. Nine U.S astronauts were selected for commercial crew flight assignments by NASA in August 2018. (L to R) Sunita Williams, Josh Cassada, Eric Boe (replaced later by Mike Finckel), Nicole Aunapu Mann, Chris Ferguson, Doug Harley, Bob Behnken, Mike Hopkins, and Victor Glover. Image NASA.Americas Space OdysseyNASA has formed partnerships with Boeing and SpaceX, two of the biggest commercial players in the aerospace industry, with a goal to once again launch American astronauts from American soil to the ISS. The Commercial Crew Program was laun ched in September 2014 when NASA awarded contracts to Boeing and SpaceX, valued at up to $4.2 tausend milliarden and $2.6 billion, respectively, tasking the companies with developing and testing new spacecraft that could work as a safe, reliable, and cost-effective replacement for the Space Shuttle.Recommended for You Top 10 Space Missions Set to Explore New FrontiersWhat you see in the U.S. originated during the second Bush administration when NASA administrator put 500 million dollars to stimulate the commercial market where NASA wants to buy services as opposed to own the entire system, said Horack, who has 30 years of experience in the space industry, with 17 of those at the agency. NASA has been successful in the cargo area, and we are now in the situation that we will do that with human beings, he added.What makes the program unique is that commercial companies are free to design in a way they think is best and are encuraged to apply their most efficient and effective manufact uring and business operating techniques. The companies own and operate their hardware and infrastructure. NASAs engineers and aerospace specialists work closely with the commercial companies, allowing for substantial insight into the development process and offering up expertise and available resources.Editors Pick Sunita Williams Soars WeightlesslyAs part of the commercial crew program, Boeing and SpaceX are developing the CST-100 Starliner and Crew Dragon spacecraft, respectively. This year could also see both companies delivering astronauts to the ISSwhich could mean the end of NASA buying seats on Russian rockets. Chris Ferguson who led the final mission of Americas space shuttle program, will return to the ISS as a commercial test pilot of the CST-11 Starliner spacecraft. Image The Boeing CompanyPublic-private partnerships like the commercial crew program are great ways for government agencies to encourage growth in the private sector and foster commercial capabi lities that used to only be available to the government, said astronaut Chris Ferguson, who led the final mission of Americas space shuttle program, and will return to the ISS as a commercial test pilot of the CST-100 Starliner spacecraft. The innovation that will come from these partnerships wont necessarily be new capabilities, but making the capabilities, were building better and more efficient and cost-effective.For the first time since 2011, we are on the brink of launching American astronauts on American rockets from American soil, said NASA Administrator Jim Bridenstine at an event held at the Johnson Space Center in Houston in August 2018, where NASA announced the names of astronauts who would fly on the crewed test flights planned for the CST-100 Starliner and Crew Dragon. This accomplished group of American astronauts, flying on new spacecraft developed by our commercial partners Boeing and SpaceX, will launch a new era of human spaceflight, Bridenstine added.NASA astronau ts Robert Behnken and Douglas Hurley were selected for the SpaceX crewed test flight. The astronauts flew on two shuttle missionsHurley was on the final shuttle flight, STS-135. The first Crew Dragon post-certification mission will be flown by Victor Glover, another rookie astronaut selected in 2013, and Mike Hopkins, who spent 166 days on one mission.The Boeing crewed test flight will carry three people. Ferguson will be joined by Mike Fincke, another veteran astronaut, and Nicole Aunapu Mann, a member of the astronaut class of 2013. The first Starliner post-certification mission will fly astronauts Josh Cassada and Sunita Williams. Cassada is a rookie astronaut selected in 2013, while Williams, the fourth astronaut selected for commercial crew training, has spent 322 days in space on two long-duration ISS missions.The nine astronauts are currently undergoing specific mission training and working with Boeing and SpaceX to understand every aspect of the new spacecraft and launch sys tems, the spacesuits, and refining how theyre going to operate in space.The Right StuffAs part of the public-private partnership, NASA is working closely with SpaceX and Boeing throughout design, development, and testing to ensure the systems meet its safety and performance requirements. When I landed STS-135, I thought my spaceflight days were done, said Ferguson, who as Boeings director of crew and mission operations is overseeing the design of the Starliner. I was satisfied with my career, but when Boeing came knocking, I couldnt refuse the opportunity to help build and perhaps fly the next human-rated spacecraft since the Space Shuttle. The CST-100 Starliner comprises a crew module and a service module. The crew module will carry the crew and cargo. It also includes communication systems, docking mechanisms, and return systems for Earth landing. The service module provides propulsion in orbit and in abort scenarios as well as radiators for thermal control.Ferguson, who had a han d in designing Starliners piloting displays and console, said the console design is much different than the shuttle. Were talking dozens of switches and dials versus hundreds. All our critical systems can be controlled with physical switches and dials, which is a choice we made to make sure crews have the greatest amount of control if they need to take over.The Starliner is a reusable aircraft that can land on solid ground rather than landing in the ocean. I dont have any insight into Crew Dragon, but one immediately obvious difference is that we land on dry land opposed to sea landings, and to do that we use an innovative parachute and airbag system, which helps make our crew module reusable up to ten times, said Ferguson.In addition, it is designed to fly its entire mission profile completely autonomously. That presents its own set of challenges, said Ferguson, adding that the flight software, avionics, docking sensors and propulsion, reentry and landing systems all have to work c ompletely independently without human input. Manual controls are there as a safety valve.If we see something we dont like or if the system is doing something its not supposed to, we can take over and get the vehicle back on track. Integrating the autonomy and manual control such that the transitions are seamless has been a unique challenge, he said. SpaceX, on the other hand, is using its Dragon spacecraft, which has carried cargo to the ISS since 2012. The Dragon is capable of carrying up to seven passengers to and from Earth orbit. The pressurized section of the capsule is designed to carry both people and environmentally sensitive cargo.Toward the base of the capsule and contained within the nose cone are the Draco thrusters, which allow for orbital maneuvering. Dragons trunk not only carries unpressurized cargo but also supports the spacecraft during ascent. The trunk remains attached to Dragon until shortly before reentry into Earths atmosphere.To support human spaceflight, Cre w Dragon features an environmental control and life support system. The spacecraft is equipped with a launch escape system capable of carrying crew to safety at any point during ascent or in the unlikely event of an anomaly on the pad. While the crew can take manual control of the spacecraft if necessary, Crew Dragon missions will autonomously dock and undock with the ISS. After undocking from the space station and re-entering Earths atmosphere, it will use an enhanced parachute system to splashdown in the ocean. We have been able to work with NASA and make tweaks as needed, said SpaceXs CEO Elon Musk about the public-private collaboration at a press conference, adding, This was in a way co-designedthere was so much feedback and interaction. NASA engineering team understands the vehicle quite well so when we make changes, we meet and confer to get it done.To Infinity and BeyondThe original goal was to have SpaceX and Boeing launch their first crewed missions by 2017, but the commerc ial crew program has been plagued with delays. If ongoing tests and reviews continue as anticipated, the companies could earn NASAs human-rating certification for passenger spaceflight this year.That would require meeting a number of benchmarks, including a requirement for both companies to demonstrate that theres no more than a one in 270 chance for a fatal accident during a flight.Spaceflight is extremely hard, Horack said. We have done it and been successful at itbut not always. We lost three astronauts in the Apollo 1 fire, seven on Challenger, and seven on Columbia. However, I am confident that these companies are doing everything they can that NASA believes is necessary to balance between making it as safe as possible and at the same time decide to go fly.Each company must launch an unmanned version of its crew capsule to the ISS, followed by a flight with a crew of two in SpaceXs Crew Dragon and three in Boeings CST-100 Starliner. After that, both companies will be certified to launch humans into low-Earth orbit SpaceX successfully flew its Crew Dragon spacecraft on a demonstration mission without astronauts onboard in March, becoming the first American spacecraft in history to dock with the ISS autonomously. The capsule spent five days docked with the ISS before returning and splashing down in the Atlantic Ocean. The company has been working toward final testing that would allow its first crewed mission later this year.In April, however, one of the crew capsules exploded during a test failure in Cape Canaveral, Fla. NASA is working with SpaceX now to investigate the incident.SpaceXs vice president of mission assurance Hans Koenigsmann said in a ansicht published by CNBC I would like to reiterate the anomaly occurred during a test, not during a flight. That is why we test. If this has to happen, Id rather it happens on the ground in the development program and I believe what we will learn from this test will make us basically a better company and Dragon 2 at the end a better vehicle, a safer vehicle.Ferguson echoes Koenigsmanns sentiment about safety. Once we put people on board, we dont get a do-over. We have to do this right the first time, and we are making sure were taking the time to do it right, he said, reiterating that When youre talking about something as complicated as a vehicle designed to send people safely to and from orbit, you have to build in redundancy on redundancy and then double and triple check those systems.Both spaceships will also rely on parachutes to deliver the crew back to Earth, so the companies are also extensively testing them with NASA. SpaceXs recent parachute test came up short of expectations.In May, Boeing shared a video of a parachute drop test for its Starliner. The video stated that Boeing will perform two such drop tests to validate the spacecrafts parachute system.Boeing has been forced to delay its tests repeatedly and is now targeting its first uncrewed flight test in August followed by t he crewed flight in late 2019. A pad abort test is also expected to occur in the coming months to demonstrate the companys ability to safely carry astronauts away from a launch vehicle emergency, if necessary.Meanwhile, NASA is considering buying two additional seats on Soyuz spacecraft to ensure a continued American presence on the ISS amid worries about additional delays in commercial crew flights.Despite the delays, the Commercial Crew Program represents a revolutionary approach to government and commercial collaborations for the advancement of space exploration. Engineers across the nation are applying their most innovative approaches to launch American astronauts back to ISS.Many other private companies including Orbital Sciences (now Northrop Grumman), Relativity Space, Blue Origin, and Virgin Galactic are developing launchers and rocket engines geared toward spaceflight.We are on the cusp of something amazing, and its quite befitting that its happening during the milestone ye ar of the Moon landing. To me, the 50th anniversary of Apollo 11 is no more a celebration than a call to action. Its a reminder that were capable of amazing achievements, but to do them, we must have a clear goal and a singular focus and drive, Ferguson said. Reclaiming the ability to send crews to orbit is a good start, and whatever we do next, whether an outpost in deep space, the Moon, or even Mars is less important as long as we commit to going somewhere, and then go.Chitra Sethi is the managing editor of Mechanical Engineering magazine.
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