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.

SpaceX delayed its seventh test launch of Starship by 24 hours on Wednesday due to weather concerns, pushing 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.