During re-entry and landing burns that began around 6 minutes and 8 minutes respectively into the flight, one or more of the booster's grid fin hydraulic pumps stalled, sending the plummeting rocket off course from its planned landing site.
As it continued to descend, the rocket is seen in video to begin to spin like a slowly twirling pencil in a counterclockwise motion, the Merlin engine's beneath it fighting to stabilize its flight.
"We have had a great liftoff", said SpaceX commentator John Insprucker, as the Falcon 9 rocket soared into the sunny, blue sky over Cape Canaveral, Florida at 1:16 pm [1816 GMT], carrying 5,600 pounds [2,500 kilograms] of gear.
Unplanned water landing of Block 5 Falcon 9 used on the CRS-16 mission.
The first stage, meanwhile, tried to come back for a vertical landing at Cape Canaveral.
MSDH reports first flu case of 2018-2019 season
The Indiana State Department of Health is urging anyone, who hasn't received their flu shot yet, to get one now. Influenza activity is now at low levels in Montana; however, this is expected to change in the coming weeks.
A new video gives an incredible rocket's-eye view of a SpaceX booster's unsuccessful bid to return to terra firma today (Dec. 5).
Falcon 9 is now the only reusable rocket booster, which is a major selling point for SpaceX.
SpaceX CEO and lead designer Elon Musk tweeted that the reusable booster was undamaged and appeared to be transmitting data. "Recovery ship dispatched", Musk said via Twitter today. The capsule should reach the 250-mile-high outpost Saturday; it also visited in 2017.
Ocean platform landings have proven a bit trickier, but SpaceX has managed to stick the landing, whether on land or sea, 32 times in all. It pops out its four landing legs, rockets toward the ocean's surface, plunges in, then tips over like a felled tree. "Given this event, we will likely add a backup", Musk tweeted.
Wednesday's Falcon rocket was brand new, while the Dragon cargo carrier was recycled by SpaceX.
But in this case, nothing that'd be considered critical to NASA's mission - only SpaceX's convenience - seems to have gone wrong. The crew-carrying version of Dragon is schedule to fly a test mission next month, and if all goes well, will carry astronauts to the station later in the year in what would be the first crewed flight from USA soil since the space shuttles retired in 2011.