Apr 24

SpaceX Brings a Booster Safely Back to Earth

space_x_Falcon9Imagine what it would cost to fly from Denver to Orlando if the airplane could only be used once and a new one had to be built for each flight.  This is the cost model that we have historically used when it comes to space flight.  Even the Space Shuttle (which was intended to address this issue) required significant rebuild and refurbishment after each flight. Imagine how much less space flight would cost if we were able to land a rocket after a launch, fill up the fuel tanks, and then use it again (like we do airplanes or cars).

Space Exploration Technologies, or SpaceX, took a step toward making spaceflight less expensive by reusing its rocket boosters during a mission on Friday to the International Space Station. The Falcon 9 rocket used for the mission, dubbed Commercial Resupply-3, or CRS-3, was the first to fly with landing legs, and was the first to successfully perform a controlled ocean splashdown.

The launch of the third official cargo delivery mission by SpaceX to the station had been delayed from last month and again from Monday due to technical problems.

The rocket, carrying a Dragon space capsule loaded with 3,500 pounds of supplies for the space station, lifted off at just after 3:25 p.m. EST. The Dragon spacecraft reached the space station on Sunday.

The mission was the first successful test of a new capability for the first stage of the Falcon 9: the ability to descend to a soft touchdown after delivering its payload to orbit. Conventional rocket boosters fall back to Earth after expending their fuel, reëntering the atmosphere fast enough to disintegrate in the heat caused by friction with the air. This adds greatly to launch costs, which can top $200 million per launch, since a new rocket has to be built for each flight (see “SpaceX to Launch World’s First Reusable Rocket”).

SpaceX is already the lowest-cost provider of launch services to the U.S. government and the commercial satellite industry, with flights costing less than $100 million. The company hopes to drop costs even further with reusable rockets. SpaceX has been testing a Falcon 9 first stage in low-altitude hops at its McGregor, Texas, rocket development and testing center. The company posted a video of a test flight that took place last week with the same type of landing legs used on Friday’s orbital flight.

A camera on the second stage of the rocket captured live video of the nine SpaceX-built Merlin engines firing on the first stage of the rocket, with the plume of flame and smoke gradually expanding as the air around the vehicle thinned. At about 50 miles in altitude, and traveling at about 10 times the speed of sound some 35 miles off the Florida coast, the first-stage engines cut off as planned. As the first stage dropped away, the single Merlin engine in the second stage fired to propel the Dragon craft the rest of the way into orbit. Another camera view showed the Dragon moving away from the second stage into space with the Earth as a backdrop.

Meanwhile, a data link with the first stage confirmed that three of the nine engines on the first stage had fired as planned to slow the booster’s reëntry into the atmosphere. The plan then called for a single engine to restart at lower altitude over the Atlantic Ocean to enable a gentle splashdown. The second stage of the rocket was not designed to be recovered.

At a press conference about an hour and a half after the launch, SpaceX CEO Elon Musk confirmed that the initial data from the first-stage booster looked good. The booster had slowed to just over the speed of sound and had descended to about five miles, or about the altitude of a commercial airliner, before the terrestrial tracking station lost contact.


(This article stolen from MIT Technology Review)