Monday , June 27 2022

How to Land a Space Space


Regardless of the mission the astronauts have sent to accomplish, the engineers who send them must solve two basic problems: how to bring space travelers from Earth (both in orbit or on the Moon or Mars) and how We bring them back again. With decades of space-gathering experience, the space powers of the world have been unanimously established on chemical missiles as the best way to launch astronauts. The engineers of the question still debated are: What is the best way to land them?

Boeing and SpaceX, scheduled to send astronauts to the international space station next year through the NASA Crew Program, were asked to respond to two basic space issues with ingenious, economic and gee-whiz space space for cosmic challenges . However, one of the most visible elements of their spacecraft, particularly designed, will be deep in depth in the last century: they are in the form of capsules, relying on their powerful shapes and a parachute force for to slow them down from an orbital speed of 17,000 mph to a speed that human occupants can survive when they hit Earth's surface.

Space transportation had to end, however, when it took its first flight in 1981, offering comfort to the aircraft during its gentle touch on the runway. And in creating the next generation of space transport, SpaceX, at first, has really tried to lean into the future. Elon Musk and his team pushed a new type of lander, based on propelling missiles instead of parachutes, to slow down the ship and extended legs to balance it to the touch – a so-called propelling landing. "That's how a 21st-century spacecraft should land," Musk said in 2014, "Everywhere on Earth with the precision of a helicopter." SpaceX has largely succeeded in landing its propulsion for its useful cargo delivery racks – the first Falcon 9 stage, on a regular, and impressive, stand vertically on an ocean barge or back to Cape Canaveral. But such jumps with the living astronauts take time and money to keep NASA out of business with a key selling key to the economy. At least that's what observers of the space guess from Musk's abandonment of Musk's approach in 2017. So the parachutes came out again.

NASA's astronaut levels have acquired a nostalgic, if not mitic, half-century. But there were hairy things in real life. Gus Grissom almost drowned after Mercury's second flight in 1961 – a famous incident more famous for inaccurate portrayal of the 1983 film Things are right. The following year, Scott Carpenter landed 250 miles from the course and spent three hours in a lifeboat before rescue by USS intrepid.

Adventure adventures continued after the missions of the month, even after more than a decade of rapid technological breakthrough. The crews on the Skylab 4 mission in 1974 and the Apollo-Soyuz Test Project a year later ended face down in the ocean for a while, as the heavy seas caught the parachutes and put an end to the craft landing. Apollo-Soyuz's problems were complicated by a cabin propeller leakage, which required astronauts to take oxygen masks that were harder to reach as they headed down. Crew member Vance Brand came out during the fight and one of his members had to put his mask for him. In both cases, inflatable "control spheres" outside the capsule functioned as planned. The ships were spinning back to the surface, and the astronauts were relatively unharmed.

Of course, there is an alternative to landing at sea: the landing on land, which the Soviet space program then Russian does at the beginning. The Soyuz spacecraft, launched for the first time in 1967 and still strong, returns to Earth on the flat, flat land of Kazakhstan. It's not the most comfortable experience, the ex-passengers report. "It's a series of explosions followed by a car accident," said Michael Lopez-Alegria, a former NASA astronaut who returned from the International Space Station to a Soyuz in 2007. "After seven months in space, feel good."

Soyuz had an almost fatal accident in 1976, when the reentry capsule overturned the course and reached a partially frozen lake – five miles of shore at night in the middle of a blizzard. The rescuers, who arrived at the partially sank boat nine hours later, did not bother opening the hatch for two hours because they assumed that cosmonauts had frozen to death. Resilient Soviets survived, though they never flew.

Ah, good days, when US astronauts landed in the ocean and in Russian cosmonauts on land. Appeared: an Apollo capsule unchecked in 1968


A Soyuz retards his retrospectors just before the impact. Soon, US capsules will do both.

(NASA / Bill Ingalls)

When a capsule loses its footprint on the earth, the astronauts do not let hours battling up and down the waves. But they can be cold. Here, a recruiting team in Soyuz meets the crew on a Kazakh day of blizzard.

(NASA / Bill Ingalls)

However, Lopez-Alegria would prefer to return from space on the land, given the choice. "The waterfall seems to make a huge flop, so I'm not sure the impact is much smaller," he says. "And then I think I would be happier on earth than ride in the ocean." Ken Bowersox, another landing veteran from Soyuz, also believes that the earth is safer than water. "On the ground you can have a bit of a rough landing and still crawl out of your car," he notes. "If things do not work well on the water, they can become captivating pretty quickly." The description of Bowersox's re-entry of Soyuz in 2003 as "a bit of landing" may be an understatement. The capsule arrived in a ballistic landing that took hundreds of miles of target. But "I only waited a few hours," he remembers. "On the water, it would have been a lot less comfortable." As far as the impact is concerned, Bowersox compares it to the landings of the airliner carrier he is practicing as a Navy pilot. "It draws your attention, but it's no worse than a carnival ride," he says.

NASA has studied landing at different points in the pre-commuter era, but rejected it for several reasons. At the time, the agency concluded that the United States did not have a sufficiently large, empty and payable area in the neighboring countries. At least compared to the open, undifferentiated space of the Kazakh Plain, even the Southwest Desert could not compete with the canyons, the plateaus, the cities and the remnants of the reserves. Descent Targeting was not accurate enough and reliable. What the country had was a large amount of open water: the two-ocean-wide access, a coastal launch site and the existing maritime infrastructure to recover the astronauts from the water.

Another important aspect in these land surveys was the weight of the spacecraft. A landing of water can end with a diving, but the liquid still has a little bit of dedication; returning to the ground requires some extra features to deal with the harsh arrest, such as the retro rafts that the Soyuz illuminates when it's a few feet from the ground for a final brake in the seconds before the impact. This equipment, however, makes it a heavier vehicle, and in the early 60s, NASA's brainwave, pressed for time, did not think it could get all the weight per month (see the sidebar).

But technology is improving and goals are changing. Thus, Boeing revised the landing issue when designing his Starliner commercial vehicle around the year 2010. "Landing has an edge over the sea through immediate access to crew and all cargoes on board, says Michael McCarley, a Boeing career man who worked on the shuttle on his final flight before moving on to the Starliner project as the lead engineer for reentry. But the weight of this type of capsule is still a problem – or as McCarley calls it – "the mass challenge."

Soyuz could have solved his mass challenge in the year of the Beatles Sgt. Pepper, but the Russian ship can only hunt three astronauts – half of a crew of the space station. A key for the seven-passenger extended landing and ground landing replaces those retro-racked airbags. Starliner will rely on six of them (seventh in the center, only moving for an emergency water landing). They are inflated with nitrogen and oxygen like those in cars, but are designed as bicycle tires with discrete interior and exterior layers. The outer bag has holes that release the landing pressure, while the inner tube remains firm. Hopefully.

The airbag system is no easier than the Soyuz missiles, it should be easier for bodies already exhausted by half a year in space, says McCarley. Ken Bowersox is an enthusiast. "If you look at cascade men jumping from buildings and sitting on airbags, it should be a fairly reasonable landing," he comments.

Then is McCarley's personal project: the chair. In one way or another, a space capsule that returns to Earth under parachutes decreases through the atmosphere to about 4 degrees before its sudden stop, says Lopez-Alegria, who is still on the NASA's consultative council for human exploration. This compares with a tolerable 1.5G for the landing-landing spacecraft. But the impact on the bodies of astronauts depends, literally, on the place and the way they stand. Or, in fact, lying, as the backbone of man and other vital organs are not designed to absorb 4 Gs in a vertical position. Soyuz passengers already have a sloping landing with an individually designed safety system. But McCarley was determined to improve this with modern ergonomics. Begin with a bunch of plywood in the garage.

"The general concept of the chair has not changed from the plywood model, but we have added some more advanced materials," says McCarley. The company has also added 3D printing technology to form a customized seat for each Starliner passenger. Considering the compact space available, this involves intensive study of human body types.

McCarley, who is a worried one, and Starline engineer Melanie Weber, who is a little shy of five feet, was shaping up for the outer limits of the admitted dimensions. host a body type range that they gave them with the names of animals like the Orangutan ("long arms that can get virtually over the capsule", McCarley clarifies), or T-Rex (broad torso with short arms.) By designing the range the team will be more able to adapt each chair by scanning the body of an astronaut.

The Boeing team also wanted to improve the parachutes at Soyuz. For reasons now lost in the scientific history of the Cold War, the parachute series of the pilot, the drug, and finally the main vessel of the Russian ship opens from one side of the capsule, followed by the pyrotechnic release of a stiffening system that forces the capsule stays straight down. Lopez-Alegria describes the result as "a rather violent movement, as if it were a wild toad ride." Boeing promises to proceed with two chutes for symmetry, followed by three main gutters for additional redundancy stability.

As far as the capsule is concerned, the Starliner team is more comfortable with their precision landing than the NASA engineers. The company has a list of five West to Two sites, New Mexico's White Sands range, Utah Dugway Proving Ground, Edwards Air Base in California and Wilcox Playa in Arizona – and reserve locations shortly before the end of each mission. Ground crews have been combing for long forgotten phone poles and other obstacles, and have conducted extensive environmental and cultural surveys to ensure astronaut safety and the integrity of the earth. Dugway Proving Ground, for example, was set up by the military during the Second World War to test chemical and biological weapons and also happens to be an archaeological treasure of native American artifacts dating back over 13,000 years.

When astronauts Starliner-Eric Boe (on the left), Chris Ferguson (right) and Nicole Mann – return to Earth after the first mission that is equipped next year, each will be damped by fully customized chairs from their scans.

(NASA / Bill Ingalls)

Instead of Soyuz's heavy retrosurgeons, Boeing designed six lightweight airbags for Starliner (tested here at the Langley Research Center), which should have made it more comfortable to lower back to Earth.


In Nevada, Boeing tests the landing system on the Starliner capsule.


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While boeing engineers believed on the earthly details of their hard capsule descent, SpaceX began its work by dreaming of Mars. In January 2011, the company published a 15-second futuristic video that describes a spacious trapezoidal ship that makes a vertically noiseless parachute whose flames have been thrown from the four corners of its base at angles of about 30 degrees . Elon Musk, in the vocal newspaper, describes it as "a propulsion of gear, such as [how Apollo 11’s] The eagle landed on the moon. "Looks very good.

But those SuperDraco firefighters, which he later called Musk, had more to do than drop a 14,000 pound Dragon Crew Cap on a helicopter anywhere on Earth. SpaceX insisted that it could bring a similar massive sailboat to the surface of Mars, where the atmosphere is too thin to land something of this weight through parachute. The heaviest object that has so far descended was NASA's Curiosity Rover, which was about a seventh of this mass and, of course, no fragile human passenger.

SpaceX unveiled a prototype of the Dragon crew in 2014, with great hopes for its prospects on two planets. In 2016, he posted a video with a test pattern that trusted several sites over a Texas platform. Then Musk called her. While the crew's dragon was still capable of landing, he said at a research and development conference in July 2017, it would take "extraordinary efforts to qualify for safety." In addition, a much better approach to landing on Mars, the details of which he kept undercover. The capsule still contains SuperDraco engines, but they will be used only in the event of a launch disruption. (See "Abort!" Oct ./Nov 2018.) A Dragon Crew Landing Crew Crew appears destined to become a footnote for the exploration history, although SpaceX continues to work on technology for other vehicles, including next-generation BFR missile-space spacecraft still untested , which promises to transport up to 100 passengers a month or beyond. The first paying customer for this trip, the Japanese billionaire Yusaku Maezawa, was announced in September.

Fortunately, the company had a proven B plan to get the crew at the space station. While SpaceX handled the futuristic system for an equipped ship, while this magazine went to press its cargo ship, it flew in 15 missions to and from the space station, splashing the capsule without incidents. The company has so far managed to reuse four of the capsules in spite of the saltwater dune.

The crew's dragon is about 50% heavier than the cargo model, so SpaceX compensates the extra weight with a four-parachute system that delivers symmetrically over the vehicle, giving more traction than the classic triangle that swept over the 1960s. more than Boeing's Starliner, the company's statement implies: "The Dragon Crew Parachute System is the most efficient system ever designed in terms of packing density and aerodynamic braking capacity."

An even greater difference from previous days will be the modest exploitation of SpaceX to recover Dragon astronauts at sea. Published plans require a single ship of 164 feet Search Searcher, with the support of several inflatable boats that can be moved closer to the sprinkled capsule. Search Searcher will be equipped with a helipad to carry astronauts quickly to shore, if necessary.

This is a dramatic contrast with the fleet of USM steamed ships to satisfy space travel of the 1960s and 70s. No less than 24 naval vessels expected John Glenn's sprinkling after the first US orbital flight. in 1962, with the reserve air force. However, landings have become more accurate and the welcome party has dropped to four ships since the last Apollo flight in 1972. Thus, SpaceX's recovery crew was not as minimalistic as it would seem. (The company has a more sophisticated system, through a partnership with the Air Force parachute teams, to recover astronauts after a launch break.)

SpaceX is also keen to expand its reusable technology to the Dragon crew. The team has gained extensive experience in the field of water sealing and corrosion prevention since four cargo ships were restored. But now SpaceX is only approved to fly a crew with new spacecraft, creating a somewhat ironic situation if rival rival Boeing uses a reusable capsule before SpaceX. Missile observers guess that the suspension will be temporary.

* * *

Spatial human trafficking inevitably implies living in the worst scenarios. "I always think, is there something hidden that we do not know?" Says Mike McCarley of Boeing. "I looked behind each door and behind each cabinet, a personal neurosis, but also a professional neurosis." From the 1960 space flight, people's space spaces seem to involve inevitable delays and frustrating corrections at the middle of the course – from tricks, only engineers can strive to refine the entire promising system such as SpaceX's landing gear. At the beginning of the program, crew commercial missions were optimistically targeted for 2015. They are currently targeting mid-2019.

None of these should hide the fact that private entrepreneurs are constantly gaining confidence from NASA and past and future astronauts in any way they pursue. "For me, I do not care. They both will go to work," concludes Ken Bowersox. "Traveling by land or sea is an economic decision."

Also, program delays do not reverse a clear direction: crew commercial flights, retro landing systems, and all point to a new exploration space chapter where private companies take futuristic projects from asteroid mining to Mars colonization. "This is revolutionary in many ways," says Lopez-Alegria. "It is the first time the government has weakened the reins on what size was used to be. It will be a kind of revival." This is an opening for the doors that he and many others are eager to pass. Lopez-Alegria's current management is the head of business development for Axiom Space, which wants to build a privately funded successor to the space station at an estimated $ 1.5 billion cost.

First of all, however, the new commercial vehicles will come and their dramatic paradoxical return – not only on Earth, but for the first time in almost a decade in their own country.

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