SpaceX will launch Starship for a seventh test flight on Thursday, after weather concerns pushed back an experiment that will feature the spacecraft’s first payload deployment test, in what may be the latest milestone for the Elon Musk-owned aerospace company as it develops reusable rockets.

SpaceX, the private space technology company owned by Elon Musk, is asking federal authorities to approve a new round of tests for a prototype reusable rocket, but some of them may never make it back to the surface intact and will crash in the ocean.

The seventh test flight of SpaceX’s Starship ended with a successful landing of the rocket’s first stage but also the loss of the Starship vehicle