Alan Armstrong interviewed by CNN’s Brianna Keiler on Feb. 22, 2021, about the grounding of the Boeing 777 fleet following a catastrophic engine failure on United Flight 328 on Feb. 20, 2021. This  interview disclosed the fact that there were two prior catastrophic failures, one on Feb. 13, 2018, and a second prior failure on Dec. 4, 2020. The suggestion was made by Armstrong we need to develop more rigorous protocols for the inspection of the turbine blades in the PW-4000 series of engines.