SpaceX CEO Elon Musk has confirmed that the first stage of the Falcon 9 rocket that boosted the CRS-3 Dragon spacecraft into orbit made a controlled power landing on the surface of the Atlantic Ocean. The historic first controlled landing of a liquid booster was tracked by telemetry and recorded on video. Unfortunately, heavy seas destroyed the rocket before recovery operations could retrieve it.
When CRS-3 lifted off on April 18 from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida, the first stage of the Falcon 9 rocket had an oddly art deco feel thanks to a set of landing legs tucked up against the fuselage. They didn’t serve any functional part of the mission. Their main purpose was to evaluate whether the presence of the legs would interfere with the flight and to determine whether the legs could be kept from deploying prematurely.
However, SpaceX had a bonus mission for the first stage of the Falcon 9. Normally, after separating from the second stage, the spent booster would fall back into the Atlantic Ocean. This time, the booster fired its engine again for a re-entry burn. Then it deployed its legs and as it approached the surface of the ocean, it fired its engine for the last time to make a controlled soft landing at zero velocity as if on dry land. According to Musk, this had only a 50 percent chance of success, but telemetry readings indicate that the rocket did make a soft landing on the water and remained stable for 8 seconds before the data feed was lost.
“I'm happy to confirm that we were able to do a soft landing of the Falcon 9 boost stage in the Atlantic,” Musk said yesterday at a press conference at the National Press Club in Washington, DC. “All the data we received back indicate that it did a soft landing and was in a healthy condition after that. It does look like the stage was subsequently destroyed by wave action. The seas were very heavy, about 15 to 20 foot, so we suspect that the stage was destroyed due to the stormy seas, but the data is very clear that it shows a soft landing, it shows the deployment of all the legs, and the stage was in a safe state in the water.”
In addition to the telemetry, there was video as well, but this won’t be made public immediately due to its quality. “We also have a video feed, although the link was very weak,” says Musk “We’re trying to clean the video feed, so we have something that we can make sense of. We’re going to clean it up and post it on our website and try to crowdsource to see if people out there can make it even better.”
Unfortunately, the very poor weather on the day of the launch made recovery of the rocket impossible. Musk says that the seas were so heavy that even the US Coast Guard refused to put to sea. When recovery crews finally reached the area two days later, all that could be found were pieces of the interstage used to connect the first and second stages, and a portion of one landing leg.
According to Musk, this landing marks a milestone for his company and space industry in general because of its tremendous potential for lowering of launching costs. “What’s been thus far is evolutionary, not revolutionary. If we can recover the stage intact and relaunch it, the potential is there for truly revolutionary impact in space transport cost. The cost of propellant is actually only about 0.3 percent of the cost of the rocket or the mission. So, the mission costs US$60 million, the cost of the propellant is only $200 thousand.”
Musk went on to say that it may be possible in the near future to recover and launch a booster on the same day.
As to the immediate future, the water landings will be repeated on launch missions as SpaceX engineers work on making them more precise. Musk says that theoretically control can be precise as that of a helicopter. “With each successive launch, and we have several more launches this year, we expect to get more and more precise with the landing and if all goes well, I'm optimistic that we’ll be able to land the stage back at Cape Canaveral by the end of the year. If that happens, we should be able to refly the main boost stage some time next year.”
Musk's press conference at the National Press Club can be viewed here.