SpaceX Continues Torrid 2017 Launch Pace With Commercial High-Speed Inmarsat Broadband Satellite on May 15

Inmarsat-5 Flight 4 (I-5 F4) satellite undergoes prelaunch processing for liftoff on SpaceX Falcon 9. Credit: Inmarsat
Inmarsat-5 Flight 4 (I-5 F4) satellite undergoes prelaunch processing for liftoff on SpaceX Falcon 9. Credit: Inmarsat

KENNEDY SPACE CENTER, FL – SpaceX is all set to continue their absolutely torrid launch pace in 2017 with a commercial High-Speed broadband satellite for Inmarsat on May 15 following Thursday’s successful completion of a critical static hot-fire test of the first stage. Watch our video below.

The static fire test of all 9 Merlin 1 D first stage engines comes just 10 days after the last successful SpaceX Falcon 9 liftoff of the super secret NROL-76 payload for the National Reconnaissance Office, or NRO – as I reported here.

The positive outcome for the static fire test of the first stage engines of the SpaceX Falcon 9 rocket on Thursday afternoon, May 11, paves the path to a Monday evening liftoff of the Inmarsat-5 F4 mission from the Florida Space Coast.

Blastoff of the Inmarsat-5 Flight 4 communications satellite for commercial broadband provider Inmarsat is slated for Monday evening, May 15 at 7:20 p.m. EDT (2320 GMT) from SpaceX’s seaside Launch Complex 39A on NASA’s Kennedy Space Center in Florida.

“Static fire test of Falcon 9 complete,” SpaceX confirmed via social media only minutes after finishing the key test at 12:45 p.m. EDT (1645 GMT).

“Targeting launch of Inmarsat-5 Flight 4 from Pad 39A on Monday, May 15.”

The launch window extends for 50 minutes until 8:10 p.m. EDT.

Watch this cool video of Thursday’s engine test as seen from the National Wildlife Refuge near Playalinda Beach on the Atlantic Ocean.

Video Caption: Static fire test of Falcon 9 booster for Inmarsat 5 F4 launch. Testing of the 9 Merlin 1D engines of a SpaceX Falcon 9 booster on Pad 39A in preparation for launch of the Inmarsat 5 F4 satellite on May 15, 2017 from pad 39A at KSC. Credit: Jeff Seibert

“The countdown begins!” Inmarsat confirmed on the company website.

“Static fire test complete & we are go for launch! #I5F4 will fly with SpaceX on 15 May 19:20 EDT / 00:20 BST.”

The weather forecast is currently 80% GO for favorable conditions at launch time.

The never used 229-foot-tall (70-meter) SpaceX Falcon 9 will deliver Inmarsat-5 F4 to a Geostationary Transfer Orbit (GTO).

The Inmarsat-5 F4 (I-5 F4) will become part of the firms Global Xpress network “which has been delivering seamless, high-speed broadband connectivity across the world since December 2015,” says Inmarsat.

I-5 F4 was built by Boeing at their satellite operations facility in El Segundo, CA for Inmarsat.

For the purposes of the engine test only the first and second stages of the Falcon 9 were rolled up the pad and erected.

Following the conclusion of the hot fire test the Falcon 9 was rolled back off the pad to the huge SpaceX processing hangar located just outside the pad perimeter fence.

SpaceX Falcon 9 recycled rocket carrying SES-10 telecomsat poised atop Launch Complex 39A at the Kennedy Space Center ahead of liftoff on 30 Mar 2017 on world’s first reflight of an orbit class rocket. Credit: Ken Kremer/

The Falcon 9 rocket and Inmarsat payload have now been mated to the payload adapted and encapsulation inside the nose cone following the test. The integrated rocket and payload eill soon be rolled about a quarter mile up the ramp at pad 39A to undergo final prelaunch preparations.

“The #I5F4 satellite has been successfully mated to the payload adaptor and attach fitting and encapsulated into the payload fairing in preparation for our SpaceX launch on 15 May,” Inmarsat stated.

“It’s an emotional time for our Inmarsat and The Boeing Company engineers – the satellite will not be seen again before it is launched into geostationary orbit, nearly 36,000km from Earth!”

“Catch all the live action here: #GlobalXpress #makingadifference”

Inmarsat-5 Flight 4 (I-5 F4) satellite undergoes prelaunch processing for liftoff on SpaceX Falcon 9. Credit: Inmarsat

Inmarsat 5 F4 will be the sixth SpaceX launch of 2017 following the NROL-76 launch on May 1.

SpaceX Falcon 9 rocket carrying classified NROL-76 surveillance satellite for the National Reconnaissance Office successfully launches shortly after sunrise from Launch Complex 39A on 1 May 2017 from NASA’s Kennedy Space Center in Florida. 1st stage accomplished successful ground landing at the Cape nine minutes later. Credit: Ken Kremer/

Watch for Ken’s continuing onsite launch reports direct from the Kennedy Space Center and Cape Canaveral Air Force Station in Florida.

Stay tuned here for Ken’s continuing Earth and Planetary science and human spaceflight news.

Ken Kremer

Static fire test of Falcon 9 completed on May 11. SpaceX targeting launch of Inmarsat-5 Flight 4 from Pad 39A on Monday, May 15. Credit: SpaceX