https://techcrunch.com/2020/01/19/spacex-successfully-completes-key-test-of-its-crew-dragon-human-spacecraft/

SpaceX completed a crucial test of a key safety system of its Crew Dragon spacecraft today. The test involved launching its Crew Dragon using a Falcon 9, though without any actual crew on board. The launch was then intentionally cut short, with the In-Flight Abort (IFA) system triggered to separate the Crew Dragon from the rocket about about a minute and a half into the launch process.

As intended, the Dragon capsule used its eight Super Draco engines to quickly move itself away from the rocket, which in a real mission would ensure the safety of the astronauts on board the vehicle in case of any unexpected failure of the rocket. The Crew Dragon’s engines can propel it half a mile in just 7.5 seconds, exerting up to 4 Gs (4x the force of Earth’s gravity) on astronauts during this acceleration.