You are here
Reusability: The Key to Making Human Life Multi-Planetary
“If one can figure out how to effectively reuse rockets just like airplanes, the cost of access to space will be reduced by as much as a factor of a hundred. A fully reusable vehicle has never been done before. That really is the fundamental breakthrough needed to revolutionize access to space.”
SpaceX believes a fully and rapidly reusable rocket is the pivotal breakthrough needed to substantially reduce the cost of space access. The majority of the launch cost comes from building the rocket, which flies only once. Compare that to a commercial airliner – each new plane costs about the same as Falcon 9, but can fly multiple times per day, and conduct tens of thousands of flights over its lifetime. Following the commercial model, a rapidly reusable space launch vehicle could reduce the cost of traveling to space by a hundredfold.
While most rockets are designed to burn up on reentry, SpaceX rockets are designed not only to withstand reentry, but also to return to the launch pad or ocean landing site for a vertical landing. Through reusability testing during flight and on the ground in McGregor, Texas, SpaceX has made great strides toward this goal.
First Stage Landings
On December 21, 2015, SpaceX first landed a rocket first stage back on land.
Falcon 9 launched out of SpaceX’s launch pad at Cape Canaveral Air Force Station (CCAFS) in Florida carrying 11 communications satellites. As a secondary objective following the primary mission, the first stage completed a series of engine burns that steered it back toward land and slowed down its velocity, allowing the booster to softly touch down at SpaceX’s Landing Zone 1 at CCAFS. This represented the first time in history a rocket first stage landed back on Earth following an orbital mission.
Then, on April 8, 2016, during a resupply mission for NASA, a Falcon 9 first stage successfully landed on SpaceX’s autonomous spaceport drone ship in the Atlantic Ocean. The ability to recover first stages at sea is an important component of SpaceX’s reusability program because certain missions do not leave enough fuel margin for the first stage to return all the way back to land.
Since then, SpaceX has landed Falcon 9 multiple times both at land and on the drone ship at sea. These achievements were made possible by innovative engineering upgrades to the vehicle, including grid fins, cold-gas thrusters, and landing legs.
Prior to the December 2015 first stage landing, SpaceX had twice reentered a Falcon 9 first stage from space and landed it in the Atlantic Ocean. From there, SpaceX moved on to attempt using the drone ship as a landing platform in January and April 2015. While the rocket did not stick the landing on these first two attempts, SpaceX gathered important data each time and got closer to a successful landing.
Grasshopper and F9R Test Programs
SpaceX’s initial reusability tests using the Grasshopper and F9R test vehicles took place in 2012–2014 at SpaceX’s test facility in McGregor, Texas. The Grasshopper Vertical Take Off, Vertical Landing (VTVL) vehicle was essentially a Falcon 9 first stage with one Merlin 1D engine and attached steel landing legs. In 2012–2013, Grasshopper completed a series of eight flight tests with landings, the highest reaching 744 meters high. Following the retirement of Grasshopper, SpaceX began testing the F9R development vehicle, which had three Merlin 1D engines for additional thrust. F9R completed successively higher tests in 2014 topping out with a 1000m test using steerable grid fins. These overland tests provided invaluable information for future flight testing during orbital missions, ultimately leading to the first rocket landing in 2015.