SpaceX's Drone Ships

While watching SpaceX's live broadcasts, you can often hear the host say "Of course I still love you". Don't take this personally. “Of Course I Still Love You” is the name of one of the autonomous drone ships SpaceX has built to land first-stage rockets into the ocean.

The names of the other two ships used for the same job are "Just Read the Instructions" and "A Shortfall of Gravitas". These weird names refer to the spaceships in Scottish author Iain M. Banks' sci-fi series Culture.

In order to be able to be used again, the first stages of Falcon 9 rockets land about 8 minutes after takeoff, either in an area close to the launch site or on an autonomous ship located hundreds of kilometers from the launch site. If the load it sends into space is light, it has fuel to return to the launch site, if it carries a heavier payload, it does not bother to return and continues in the direction of launch and aims at the ocean platform (If it needs to benefit from its full performance, it does not make a controlled landing and the rocket is wasted).

This 41-meter-long rocket, falling from the sky at speeds exceeding the speed of sound, can harm people around if things go wrong. For this reason, landing ships are designed to operate unmanned.

Autonomous ships were initially towed and brought to the coordinates determined for landing by support ships. For several years, they have been able to make this journey on their own. At the point where they are left, they maintain their position against waves or currents with the help of GPS.

After the rocket has landed, the robot called Octagrabber, which is waiting in its sheltered area on the ship, comes under the rocket by remote control. It secures the Falcon 9 to the ship with its four arms, thus preventing the rocket from slipping and tipping over with the waves.

It takes a few days for the ships to return to the port. A fleet of several ships must be kept ready at all times in order to reuse the first stages. The process is costly and time consuming. So far, the shortest time between two launches of the same rocket is around 3 weeks.

SpaceX wants to reduce reuse to days or even hours on its test Starship rocket. Therefore, it is planned that the rocket will only land back at the launch complex.

In fact, two oil platforms, named Phobos and Deimos, the moons of Mars, were purchased in order to be used for Starship. But building an ocean platform on a system that is not yet operational would be very distracting. That's why they were disposed of.