The competition heats up: Iridium prepares the first 10 of a total of 81 new satellites for launch on SpaceX’s Falcon 9 in September.

The Iridium Next program is a $3 billion investment by Iridium, according to Matt Desch, Iridium’s chief executive officer. Iridium’s purchase of 81 satellites represents approximately $2.2 billion of that cost, Desch said, and the company’s launch contract with SpaceX for seven Falcon 9 flights was valued at $492 million when the parties signed it in 2010. That was the largest commercial launch contract in history until last year’s 21-launch order by satellite Internet provider OneWeb with Arianespace.

The first 10 Iridium Next satellites will fly on a Falcon 9 rocket in September, followed by a second launch as soon as December with the next batch. Iridium managers will give the go-ahead for the second launch once the first 10 satellites finish initial in-orbit tests, Desch said. The other five launches should occur about once every two months next year to fill out the Iridium Next fleet 485 miles (780 kilometers) above Earth. Iridium’s contract with SpaceX calls for all the missions to fly on newly-built Falcon 9s, a situation unlikely to change any time soon since insurance arrangements for the initial launches have been finalized.

But Desch said he is open to purchasing reused Falcon 9 boosters in the future “if they’re the right price.”

To meet this schedule SpaceX’s launch schedule will have to ramp up considerably from its present rate of one launch about every three weeks.