SpaceX performed a hold-down test-firing of the Falcon 9’s first stage Merlin engines Friday. The test-firing is a customary pre-launch checkout before every SpaceX mission, providing a test of launch vehicle systems and a rehearsal for the company’s launch team.

The Falcon 9 was raised vertical at pad 40 without its satellite payload or fairing Friday in preparation for the static fire test. SpaceX loaded super-chilled, densified kerosene and liquid oxygen propellants into the two-stage Falcon 9 rocket, and the countdown proceeded through through the final steps before launch, including retraction of the strongback structure into position for liftoff and pressurization of the rocket’s propellant tanks. //

The nine Merlin 1D engines at the bottom of the Falcon 9’s first stage ignited for several seconds at 1:20 p.m. EST (1820 GMT) Friday, throttling up to full power to generate some 1.7 million pounds of thrust as hold-down restraints keep the rocket firmly on the ground.

SpaceX engineers will perform a data review after the static fire as technicians at Cape Canaveral roll the rocket back to the hangar and prepare to mate it with the JCSAT 18/Kacific 1 communications satellite inside a climate-controller hangar.//

The Falcon 9 rocket slated to launch the JCSAT 18/Kacific 1 spacecraft is a veteran of two previous missions. It first launched in May on a space station cargo mission, then landed on SpaceX’s drone ship in the Atlantic Ocean. On its second flight, the rocket again powered a Dragon supply ship toward the space station, and returned to Cape Canaveral for an onshore landing.

SpaceX is expected to recover the first stage again after Monday’s launch aboard a drone ship in the Atlantic east of Florida’s Space Coast.

The 15,335-pound (6,956-kilogram) JCSAT 18/Kacific 1 spacecraft will launch into an elliptical transfer orbit, then use its on-board liquid-fueled engine to maneuver into a circular geostationary orbit more than 22,000 miles (nearly 36,000 kilometers) over the equator.