Iridium plans to launch its fourth batch of NEXT satellites in December, bringing the total number to 40 out of the 66 planned to be operational by mid-2018. The constellation includes another nine orbiting spares and six more ground spares.
Among hosted payloads on NEXT, the Aireon network of Automatic Dependent Surveillance-Broadcast (ADS-B) receivers supplied by Harris is already transmitting more than 3 billion ADS-B messages.
