The recent availability of an electronically steered, phased-array antenna makes possible faster, more affordable, lower power broadband connectivity through next-generation low Earth orbit SatCom constellations, such as OneWeb, Starlink, and eventually Amazon Kuiper.
minimum flight altitude for using LEO IFC, assuming your aircraft is in line-of-sight of a LEO satellite. Three main LEO contenders offer IFC for business aircraft. Iridium Satellite Communications is the incum- bent and now operates a constellation of 66 second-gen- eration, L-band Iridium NEXT space vehicles, plus 14 spares, in six polar orbits 422 nm above the Earth. L-band SatCom IFC, because of its lower frequency and longer wavelength, is virtually immune to precip- itation attenuation. By international agreement, cer- tain L-band frequencies are reserved and protected for aeronautical mobile satellite (route) service. So-called “safety service” L-band SatCom is used for the Future Air Navigation System’s (FANS) ADS-C (automatic de- pendent surveillance-contract, as opposed to broadcast in ADS-B) and CPDLC (controller/pilot data link com- munications), functions that allow oceanic air traffic controllers to see the current and estimated positions of aircraft and receive requests from and transmit instruc- tions to FANS-equipped aircraft. Iridium is the only LEO satellite operator that offers L-band FANS connectivity, as its license covers a protect- ed 1,610 MHz to 1,626.5 MHz L-band frequency block. For pilots and passengers, Iridium claims its Certus 700 IFC system is capable of download speeds as fast as 704 kilobytes per second (Kbps) and upload speeds of up to 352 Kbps. Outside observers say typical speeds are closer to 432 Kbps down and 216 Kbps up. This is sufficient for me-
dium resolution datalink text, graphic weather products for flight crews, and emails or text messages with small attachments for passengers. Iridium L-band IFC avionics and subscriptions are available through many GA avionics firms, including Collins Aerospace, Garmin, and Honeywell. If you plan on flying in transoceanic FANS1/A airspace, Iridium L-band IFC is the least expensive route to equipping your aircraft with the required SatCom equipment. For aircraft operators desiring appreciably higher IFC speeds, OneWeb is building a constellation of 648 KU- band LEO satellites to be placed in 12 650-nm-high po- lar orbits. The firm has overcome two major challenges: The first was a March 2020 bankruptcy related to the economic impact of COVID-19. Bharti Global and the United Kingdom bailed out OneWeb from bankruptcy. Subsequent cash infusions from SoftBank and Hughes Network Systems, among other firms, enabled OneWeb to resume launching space vehicles. The firm merged with France’s Eutelsat GEO satellite organization in mid-2022, further bolstering its financial strength. The second challenge was OneWeb’s reliance on Rus- sia to launch two-thirds of its satellites using the Soyuz-2 heavy rocket. Sanctions on Russia in the wake of its Ukraine invasion caused OneWeb to lose that capability and also $50 million of satellites held captive by the Russians. SpaceX and NewSpace India have filled in the launch capacity lost to Russia. Currently, there are more than 580 OneWeb satellites in orbit and functioning. Users can
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