Rocket Recycling
Tuesday, April 18th, 2017April 18, 2017
Late last month, Space Exploration Technologies Corporation (commonly called SpaceX) made aerospace history. After propelling a communication satellite into orbit, the first stage of one of the company’s Falcon 9 rockets landed on a drone ship (uncrewed barge) in the Atlantic Ocean. But this booster had been there before. SpaceX successfully reused a booster that had been launched during a previous mission. The achievement has been widely hailed as the dawn of a new era in commercial spaceflight.
A rocket is a type of engine that pushes itself forward or upward by producing thrust. Unlike a jet engine, which draws in outside air, a rocket engine uses only the substances carried within it. As a result, a rocket can operate in outer space, where there is no air.
SpaceX is a private space exploration company founded by South African entrepreneur (business developer) Elon Musk. On March 30, one of the company’s multistage Falcon 9 rockets lifted off from Kennedy Space Center in Florida. In a traditional multistage rocket, discarded stages fall to Earth or burn up in the atmosphere. In recent SpaceX launches, however, the first stages of Falcon 9’s descend either to a landing pad or a floating drone ship and land vertically–and safely. The first stage in question had been used during an April 2016 mission and, on that first mission, was the first booster to land on a ship at sea. For this year’s mission, it again landed successfully on the drone ship Of Course I Still Love You. SpaceX also recovered part of the Falcon 9′s fairings, the nosecone sections that protect the payload. The recovered section, measuring 43 feet (13 meters) long and 17 feet (5 meters) in diameter, splashed down via parachute not far from the drone ship. It can also be reused, saving millions of dollars.
Engineers have toyed with reusing rockets before. Notably, the United States space shuttles were partly reusable. These airplane-like orbiters could land on a runway and be reused, and the boosters were towed back to land by ships and were refurbished. But each orbiter had to be extensively examined and repaired after each flight. Even with such precautions, booster failure and heat shield damage destroyed orbiters in 1986 and again in 2003, killing 14 astronauts together. The shuttle program, which ran from 1981 to 2011, made just over 100 flights and cost over $200 billion—far more than traditional rockets would have cost to fly the same number of missions.
Learning from the failures of the space shuttle program, many new private space companies have based their business models on reusability. Blue Origin, a rocket company owned by American businessman Jeff Bezos, has successfully landed and reused stages of its experimental New Glenn rocket, with an eye toward both commercial satellite launches and space tourism. Virgin Galactic, a company founded by British businessman Richard Branson, is testing a space-tourism rocket that is released from a special airplane and lands on an Earth-bound runway like the space shuttle orbiters did.
Reusability has the potential to make spaceflight far cheaper than it is today. Imagine if, after one flight, an airplane had to be thrown away. Air travel would be incredibly expensive. Reuse of rocket parts will allow satellites to be launched more cheaply and will make space travel accessible to tourists–albeit wealthy ones. By reusing the first stage and fairings, it is estimated that SpaceX could cut costs by 70 percent.
Musk has already outlined the company’s next goal: he wants to fly two missions with the same booster within 24 hours. It took almost a year for SpaceX to examine and refurbish this booster, but Musk is confident that the lessons learned will both speed up the refurbishment process and inform the design of the next version of the Falcon 9, which is scheduled to fly within the next year.
Despite the enormity of this achievement, Musk has stated that true success will come when these launches become automatic. When it becomes routine to recover and reuse rocket parts, the true potential of spaceflight may soon be realized.