It was the first time that the company reused side boosters for the Falcon Heavy, with the two that flew today having completed their first mission in April of this year. This was also the first Falcon Heavy launch to carry U.S. Department of Defense (DoD) satellites — the total payload of satellites onboard hailed from DoD research labs, NASA, the National Oceanic and Atmospheric Administration and U.S.-based universities.
After liftoff, the flight plan involved four separate upper-stage engine burns, three payload deployments in different orbits, and then firing the engines on all three (now separated) boosters for the return to Earth. The two side boosters landed themselves safely back at Cape Canaveral. The center core was supposed to land on a recovery ship in the Atlantic Ocean; however, it missed its target and exploded when it hit the water.
According to SpaceX CEO Elon Musk, this fate for the center core was not entirely unexpected: “Odds of center core surviving are about 50 percent in my opinion, as it's coming in about four time times faster than a rifle bullet.”
