IATA has welcomed the agreement by AT&T Services,
T-Mobile, UScellular and Verizon to extend until 1 January 2028
the voluntary mitigation measures for 5G C-band transmissions at
188 US airports.
The measures, which were put in
place in January 2022, concurrent with the rollout of 5G C-band
operations at or near US airports, include lowering the power of
5G transmissions and had been set to expire 1 July 2023.
However,
while the agreement is a welcome stop-gap development, it is by no
means a solution. The underlying safety and economic issues around
5G C-band deployments by telecommunications services providers (telcos)
remain.
“Airlines did not create this situation. They are
victims of poor government planning and coordination,” said Nick
Careen, IATA’s Senior Vice President Operations, Safety and
Security. “Industry
concerns about 5G, expressed for many years in the appropriate
forums, were ignored and over-ridden. Half-measure solutions have
been foisted upon airlines to implement at their own expense and
with little visibility into their long-term viability. This
extension is an opportunity for all stakeholders, including telcos,
government regulators, airlines and equipment manufacturers, to
work together for a fair and equitable solution.”
The activation of 5G C-band operations in January
2022 threatened enormous disruption to the US air transport system
because of the potential risk of interference with aircraft radio
altimeters (radalts) that also use C-band spectrum and are
critical to aircraft landing and safety systems.
The issue was only addressed at the eleventh hour
when AT&T and Verizon agreed to a voluntary power limit for 5G
C-band transmissions near airports.
Even with that agreement, however, the continuing risk of
interference with aircraft radalts was seen as so significant by
the Federal Aviation Administration (FAA) that airlines were only
permitted to operate at affected airports in low visibility
(Category 2 and Category 3) conditions through one of two methods:
– Alternative Means of Compliance (AMOC) under
which avionics and aircraft original equipment manufacturers
(OEMs) establish that specific aircraft / radalt combinations
provide sufficient resilience against interference to continue to
utilize low visibility landing procedures at the affected
airports.
– Modifying existing radalts or replacing them
with newer models at their own expense, to enable unrestricted
operations at agreed 5G power levels.
In May 2022, the FAA informed airlines that, as of
1 July 2023 the AMOC process would end. In its place, a blanket
requirement defining a minimum performance level for radalts for
low visibility landing procedures was to be established.
Radalts
not meeting the minimum performance level would have to be
replaced or upgraded at airline expense with the cost of fleet-wide radalt upgrading estimated at more than $638 million.
Several airlines began the radalt upgrade process
shortly after the May 2022 communication from the FAA, even though
the FAA did not issue a formal notice of proposed rulemaking until
January 2023. Even then, supply chain issues make it unlikely that
all aircraft can be upgraded by the 1 July deadline, threatening
operational disruptions during the peak northern summer travel
season.
The latest agreement by the telcos to defer until
January 2028 full power-up of 5G C-band transmissions near
airports buys time but does not address underlying issues.
The retrofits required by 1 July 2023 are a
temporary fix as they are not sufficiently resilient in the face
of full power 5G C-band transmissions. New 5G tolerant radalt
standards are being developed but are not expected to be approved
before the second half of 2024. Following that, radalt makers will
begin the lengthy process to design, certify and build the new
devices for installation in thousands of existing aircraft, as
well as for all new aircraft delivered between now and 2028.
Four-and-a-half years is a very tight timeframe for the scale of
this undertaking.
“Many airlines have indicated that despite their
best efforts they will not meet the 1 July deadline owing to
supply chain issues. But even for those that do, these investments
will bring no gains in operating efficiency,” said Careen.
“Furthermore, this is only a temporary holding action. Under
current scenarios, airlines will have to retrofit most of their
aircraft twice in just five years. And with the standards for the
second retrofit yet to be developed we could easily be facing the
same supply chain issues in 2028 that we are struggling with
today. This is patently unfair and wasteful. We need a more
rational approach that does not place the entire burden for
addressing this unfortunate situation on aviation.”
