Updated June 22, 2017 at 10:31 a.m. Eastern.

WASHINGTON — Mobile satellite services provider Iridium is willing to use pre-flown Falcon 9 first stage boosters for missions during the second half of its fleet replacement if SpaceX can show that reuse will shorten Iridium’s wait for launches.

Iridium is launching 75 of its 81 second-generation Iridium Next satellites using eight Falcon 9 launches, the first of which took place Jan. 14. In a conference call with reporters June 19, Desch said Iridium’s original contract with SpaceX calls for new Falcon 9s for each mission, but if SpaceX can improve its launch schedule with pre-flown stages, Iridium would consider them for missions in 2018.

“While we are currently flying first flown launches, I’m open to previously flown launches, particularly for the second half of our launch schedule,” said Desch.

Desch said there are three criterion by which Iridium would decide whether to use a pre-flown rocket: schedule, cost and reliability — of which schedule is the most important.

“Would [pre-flown rockets] improve the current launch plan that I have with brand-new rockets that I’ve basically contracted for a number of years ago and have budgeted for and have paid for?” Desch asked. “That’s the first thing: will they improve my schedule, because schedule to me is very very important.”

Iridium had hoped to have the entire Iridium Next constellation in orbit by the end of 2017, but both manufacturing setbacks and launch delays offset that goal. Thales Alenia Space, who is building the Iridium Next satellites with Orbital ATK in Arizona, pushed the first launch back by four months in 2015 to allow for additional testing. SpaceX then experienced two Falcon 9 failures — the loss of NASA’s Commercial Resupply Services 7 mission and the Amos-6 rocket fueling anomaly — delaying the first Iridium Next launch to this January. Two satellites that were supposed to launch on a Dnepr rocket from Kosmotras never received Russian approval, leading Iridium to rebook them, along with another three satellites, on an eighth Falcon 9 as co-passengers with a U.S.-German science experiment.

Those delays meant revenue Iridium was counting on to pay back Thales Alenia Space and a $1.8 billion Coface credit facility this year wasn’t there, prompting the company to ask for extensions on those payments.

The second launch of 10 Iridium Next satellites is scheduled for June 25, with a backup date of June 26. Following that mission, Desch said the next six missions all occur over 12 months. The complete constellation is to consist of 66 operational satellites, nine in-orbit spares and six ground spares.

Desch said Iridium views the pro of a lower-cost launch, with reuse, as roughly equal to the con of increased risk from a system that is still being proven. Both the cost savings and the new risk are low, he said. Desch didn’t say how much of a discount SpaceX offered for a pre-flown booster, but said the price needs to come down more in order for it to be convincing. “That may change,” Desch said of the discount, “and I can tell you over the coming months if that changes, as there are additional launches I’ll reconsider that, but right now I think we’ve made the right decision.”

SpaceX completed its first flight with a pre-flown first stage in March, orbiting the SES-10 satellite, and has another, BulgariaSat-1, slated for June 23 or 24.

Aireon gaining speed, but still on the runway

Iridium’s joint venture for global aircraft tracking, Aireon, has been similarly hamstrung by Iridium Next delays, since its network of sensors are all flying as hosted payloads on the Next satellites.

Aireon has a $200 million hosting fee it must pay Iridium, but needs global coverage in order to start generating substantial revenue. The company’s business case rests on tracking aircraft beyond the reach of radar, improving safety and fuel efficiency by allowing pilots to fly more optimal routes.

Don Thoma, Aireon’s CEO, said the company has eight active payloads tracking Automatic Dependent Surveillance-Broadcast (ADS-B) signals from aircraft, because eight of the first 10 Iridium Next satellites are stitched into the Iridium network from the first launch. The last two are still on their way to their respective orbits.

Thoma told SpaceNews that Aireon is raising capital this summer “based upon the success of our sales efforts and business to date.”

“It’s our intention to pay Iridium some or all of their hosting fee based on how much capital we are able to raise,” he said.

During the call, Thoma said Aireon is working with 10 customers today, and has another 10 testing the service. Aireon currently covers 12 percent of the world, he said, and has been able to pull off a number of firsts, including flight tracking over polar regions and previously uncovered ocean areas.

Thoma said it takes roughly 45 days from launch until the ADS-B payloads are turned over to Aireon. He said the company needs the next five to six launches complete before it can begin offering a service called GlobalBeacon with FlightAware, a flight-tracking-data company. GlobalBeacon uses Aireon’s space-based ADS-B to track aircraft every minute, and enables aircraft to meet the International Civil Aviation Organization’s upcoming Global Aeronautical Distress Safety System (GADSS) standards. GADSS requires aircraft to report their location at least once every 15 minutes.

Aireon and FlightAware plan to launch the service next year with Qatar Airways. Malaysia Airlines, whose lost flight MH370 triggered widespread awareness of the limited nature of flight tracking, is launching the service with Aireon, FlightAware and aeronautical flight tracking and connectivity company SitaOnAir. Aireon will supply space-based ADS-B data to more than 3,000 aircraft that are currently provided a tracking service called Aircom FlightTracker from SitaOnAir.

And then there were (almost) two

Desch said Iridium is significantly closer to breaking Inmarsat’s monopoly on Global Maritime Distress and Safety System, or GMDSS, satellite services, which are used to contact rescue personnel during maritime emergencies. The International Maritime Organization (IMO) began evaluating Iridium’s ability to provide GMDSS services in 2014.

Desch said IMO approved a new performance performance standard for GMDSS equipment and revisions to the Safety of Life at Sea (SOLAS) treaty — two steps Iridium needed — last week. The third and final step Iridium needs is “an IMO resolution specifically recognizing Iridium as a GMDSS service provider,” he said.

In an email to SpaceNews, Desch said Iridium “expect[s] to achieve IMO recognition in 2018 with service to begin when the SOLAS treaty amendments [are] going into force, which wouldn’t likely be before January 1, 2020.”