SpaceX had made 27 successful landings since June 2016, according to Spaceflight Now. This landing, while not 100% successful, was smooth enough that SpaceX CEO Elon Musk tweeted that the company may re-use the rocket for an internal mission.

Just before the rocket landed at Cape Canaveral a stabilizer fin failed to deploy, causing the rocket to spin, as shown in this video:

The rocket engines compensated somewhat for the spin, and by the time the rocket hit the water, its fin had emerged. The wet landing was gentle enough that the rocket remains intact. Musk tweeted that SpaceX will likely add a backup pump to make the fin stabilizing system more robust.

Despite the landing, the mission successfully placed in orbit its Dragon uncrewed cargo spacecraft. The Dragon should deliver its 2.5 ton payload to the International Space Station Saturday.

“The important point here is we have a safety function on board that makes sure the vehicle does not go on land until everything is OK, and that worked perfectly,” SpaceX vice president Hans Koenisgman said.

The launch came during a busy week for space travel, with a crewed Soyuz launch and another Falcon 9 launch Monday, an Ariane 5 launch Tuesday, and a Delta IV Heavy and two Chinese lunar mission launches planned for Friday.