Updated Jan. 11, 2019 at 2:38 p.m. Eastern with the correct manufacturer for Iridium’s first-generation satellites.

WASHINGTON — Mobile satellite services provider Iridium Communications will entrust its first 10 next-generation satellites to SpaceX for a Falcon 9 return-to-flight mission now slated for Dec. 16.

The launch, planned for 12:36 p.m. local time (3:36 p.m EST) from California’s Vandenberg Air Force Base, still needs the green light from the Federal Aviation Administration, which oversaw the SpaceX-led investigation into the Sept. 1 pre-launch fueling incident that destroyed a Falcon 9 and its payload, Spacecom’s $200 million Amos-6 satellite.

“We are looking forward to return to flight with the first Iridium NEXT launch,” Gwynne Shotwell, president and chief operating officer of SpaceX, said in Iridium’s Dec. 1 press release announcing the launch date.

Iridium is banking on SpaceX to launch the majority of the Iridium Next fleet, which replaces a Motorola- and Lockheed Martin-built constellation deployed in the late 1990s. Over the course of seven missions, SpaceX is to launch 70 Iridium Next satellites 10 at a time.

“We have remained confident in SpaceX’s ability as a launch partner throughout the Falcon 9 investigation,” Matt Desch, Iridium chief executive officer, said in the Dec. 1  press release announcing the time and date of its long-awaited launch. “We are grateful for their transparency and hard work to plan for their return to flight.”

Iridium now expects to have the 70 satellites deployed by early 2018, slipping from an original completion date in 2017. Up until the Sept. 1 failure, Iridium had been adamant that other delays related to manufacturer Thales Alenia Space of France, launch provider SpaceX or range availability at Vandenberg would not push completion of the refresh of in-service spacecraft past the end of next year.

The full Iridium Next constellation consists of 66 cross-linked satellites in low Earth orbit plus  in-orbit spares. Each plane is supposed to have at least one in-orbit spare, giving a minimum number of 72 in-orbit spacecraft. The total number ordered from Thales Alenia Space and its U.S. production partner Orbital ATK is 81.

As a possible hint toward more business with its primary launch provider, Iridium’s Dec. 1 press statement said the operator would launch “at least 70” of its satellites with SpaceX. A Kosmotras Dnepr rocket was supposed to launch the first two Iridium Next satellites, but a protracted Russian regulatory process didn’t give a thumbs up in time.

It remains unclear if Kosmotras will launch any of Iridium Next. At a June 2016 press conference, Desch said there were “plans under works” for alternative launch providers in the event Kosmotras ultimately doesn’t work out. Any such providers have yet to be named.

Caleb Henry is a former SpaceNews staff writer covering satellites, telecom and launch. He previously worked for Via Satellite and NewSpace Global.He earned a bachelor’s degree in political science along with a minor in astronomy from...