Falcon 9 First Stage – Successful Landing

During my ongoing literature review I often discover interesting facts about things I’ve never thought about. Sometimes I can connect these facts with my own observations: The result is mostly a completely new idea why things are as they are. Maybe these ideas are new to you, too. Therefore I’ll share my new science based knowledge with you!

This week: This time, I think about SpaceX’s successful landing attempt of a Falcon 9 booster.

One of SpaceX’s major goals is to reduce the launch costs by developing a reusable rocket that can fly multiple times. On Tuesday, December 22, SpaceX made a huge leap towards this goal as they managed to successfully land a Falcon 9 first stage on a designated landing site.

Two and a half minutes after liftoff from Cape Canaveral, the 156-foot-tall (48m) first stage booster separated from the second stage and flipped around in order to perform a deorbit burn and to change its trajectory back to a landing site near the eastern tip of Cape Canaveral. At this point, the rocket was flying at a speed of more than 5,000 kilometers per hour at an altitude of roughly 80 kilometers. Simultaneously, the second stage ignited its engine in order to accelerate its payload to orbital velocity. After the booster completed the deorbit burn, it began its decent to the landing target and slowed down through hypersonic, supersonic to subsonic velocities. During the descent, the first stage was controlled by four hypersonic grid fins which were extended after the deorbit burn was completed.

After two unsuccessful landing attempts of a Falcon 9 first stage on a barge in the Atlantic ocean, SpaceX decided to change the landing site to a Cold War-era Atlas launch pad which was converted to support the landing attempt. Less than 10 minutes after liftoff, the Falcon 9 booster extended its landing legs and successfully landed on the landing pad.

SpaceX’s achievement marks the first landing of an orbital-class booster that was on an actual mission to transport some communication satellites into orbit. The booster is now being examined by engineers and will likely be used for ground testing. However, it will probably not fly again, but future boosters might get refurbished for multiple missions.

Well done, SpaceX!