CASSIOPE

Debut flight of Falcon 9 v1.1, the stretched, uprated variant with an octaweb engine layout and the Merlin 1D engine — SpaceX's first orbital launch with that engine. Also the first Falcon 9 from Vandenberg and SpaceX's first mission for a fully private commercial customer.

After delivering CASSIOPE and its five co-manifested satellites, the first stage conducted the earliest known attempt at supersonic retropropulsion by reigniting an engine during descent. The test returned useful data: the stage completed a controlled reentry and a landing burn over the ocean, but began rolling as it neared the surface, depleting one engine's fuel until it shut down, and the stage hit the water hard. The data informed SpaceX's subsequent partnership with NASA on Mars entry, descent, and landing research.