The FAA announced earlier this month that it will no longer expect aircraft with Automatic Dependent Surveillance-Broadcast (ADS-B) Out equipment using the Selective Availability (SA)-Aware receivers to perform a preflight availability prediction before operating in ADS-B rule airspace. The policy went into effect on May 10, 2022.
Data retrieved over seven years found that "SA-Aware GPS receivers achieved 99.9%, or greater, operational availability."
Additionally, the policy noted that the FAA agreed in the performance of SA-Aware GPS receivers was equivalent to, or better than, a single radar since the agency had begun monitoring ADS-B performance in 2015.
For aircraft equipped with GPS receivers that do not meet the performance requirements of TSO-196 or TSO-C145/146, the pilot is still required to run a preflight prediction.
The policy statement also touched on circumstances "outside of an operator's control" that may cause GPS performance to falter, putting the operator in apparent violation of § 91.227.
The FAA says it will not take legal action for apparent noncompliance for the following: experiencing rerouting by ATC after obtaining an initial ATC route clearance; GPS interference on the intended path of flight; FAA's SAPT being out of service.
Read the policy statement in full.