But the rocket gods were with SpaceX today and the Falcon 9 touched down just slightly off center on the “Of Course I Still Love You” drone ship. There was no drama, just a picturesque landing that caps off years of development and gallons of sweat and tears. Landing on a drone ship is an incredibly difficult task, as SpaceX not only has to control a multi-story tall rocket that is hurtling back to earth, but you also have to take into account the floating platform that is bobbing up and down, and moving about in the ocean.
But the increased difficulty of landing at sea has the added benefit of the Falcon 9 not requiring as much fuel for its return trip. Since rockets travel on a parabolic trajectory up into orbit, a landing at sea is easier to achieve logistically (launches from Cape Canaveral arc up over the Atlantic). In addition, the drone ship can be placed in an optimal spot in the ocean to retrieve the Dragon 9 depending on the amount of payload the rocket is carrying and how far it has to travel into space before making its return trip.
The 1st stage of the Falcon 9 just landed on our Of Course I Still Love You droneship. Dragon in good orbit pic.twitter.com/SYyUCDZE3k— SpaceX (@SpaceX) April 8, 2016
A ground-based landing, on the other hand, requires more fuel, as the rocket would have to cover more horizontal distance to get back over land (whereas in the previous scenario, the rocket would already be in prime positioning over water). The extra maneuvering to allow for a ground landing also means that more fuel must be consumed. More fuel adds to the cost and the weight of the launch vehicle, and more weight in fuel means less weight that can be used for the primary purpose of each mission: putting cargo into space.
That’s not to say that a ground-based landing is impossible. SpaceX showed us back in December that it has what it takes to make a successful ground landing, doing so on its first attempt.
But why is SpaceX even bothering to recover these rockets? It all comes down cost at the end of the day. Each Falcon 9 costs SpaceX a reported $16 million to construct, which makes it costly to discard after each and every launch. On the other hand, it costs around $200,000 to fuel that same rocket. Throwing away $16 million versus reusing the rocket, refurbishing it, and applying another $200,000 in fuel costs sounds like a better plan to us. This goes a long way towards SpaceX’s mission to drive down the cost of space travel not only for government and commercial launches, but for eventual civilian launches in the distant future.
Not everyone though is sold on SpaceX’s (and by association, Blue Origin’s) obsession with powered landings of first-stage rockets, however. Competitor United Launch Alliance (ULA) has called SpaceX’s efforts interesting but fruitless due to the amount of fuel that must be reserved to successfully recover the launch vehicle.