Enlarge / Intelsat's Galaxy 37 satellite is the last of 12 new geostationary communications spacecraft launched over the last year to clear C-band spectrum. (credit: Maxar )

A SpaceX Falcon 9 rocket launched early Thursday with the last of a dozen new C-band video relay satellites purchased by Intelsat and SES to help clear spectrum for the rollout of 5G wireless services in the United States.

Intelsat and SES, two of the world's largest geostationary communications satellites operators, are on track to receive nearly $9 billion in incentive payments from 5G cell network operators by the end of the year. The payments are due after Intelsat and SES clear the lower 300 MHz of C-band spectrum, which is being transitioned from satellite services to terrestrial 5G under the supervision of the Federal Communications Commission.

The FCC auctioned the C-band spectrum for the rollout of 5G services in 2020. Verizon and AT&T took the lion's share of the $80 billion auction.

Enlarge / Airbus 320 cockpit. (credit: Getty Images | Skyhobo )

The Federal Aviation Administration says it finally has a plan for the industry to replace or retrofit airplane altimeters that can't filter out transmissions from outside their allotted frequencies. The altimeter problem has prevented AT&T and Verizon from fully deploying 5G on the C-Band spectrum licenses the wireless carriers purchased for a combined $69 billion .

The FAA was urging airlines to retrofit or replace altimeters in recent months and now says it has finalized a plan. An FAA statement on Friday said that "airlines and other operators of aircraft equipped with the affected radio altimeters must install filters or other enhancements as soon as possible."

AT&T and Verizon said they will be able to accelerate 5G deployments near airports in the coming months, but the carriers agreed to continue some level of "voluntary mitigations" in the airport areas until July 2023.

Enlarge (credit: Getty Images | BackyardProduction)

The Federal Aviation Administration is reportedly urging airlines to retrofit or replace altimeters that receive transmissions from outside their allotted frequencies. The FAA is meeting Wednesday "with telecom and airline industry officials on a push to retrofit and ultimately replace some airplane radio altimeters that could face interference from C-Band 5G wireless service," Reuters reported Tuesday .

The Reuters report continued:

The FAA wants to use the meeting to establish "an achievable timeframe to retrofit/replace radar altimeters in the US fleet," according to a previously unreported letter from the FAA's top aviation safety official Chris Rocheleau reviewed by Reuters. It also asked aviation representatives "to offer options and commit to actions necessary to meet these objectives."

Some altimeters used by airplanes to measure altitude apparently cannot filter out transmissions from C-Band frequencies assigned to wireless carriers for 5G. Altimeters are supposed to use frequencies from 4.2 GHz to 4.4 GHz, while wireless carriers' C-Band licenses are for 3.7 to 3.98 GHz.