https://en.wikipedia.org/wiki/Air_India_Flight_2379
The cascade of fault warnings as recorded by the digital flight data recorder, all of which occurred within a minute,[4] involved the three multiply redundant hydraulic systems, elevator flight-controls, autopilot disconnection, an emergency exit door, and even an engine anti-ice warning.[5] The Airbus A320 has three independent hydraulic systems, coded blue, green, and yellow, such that the loss of all three is considered by experts to be virtually impossible. (Too, this aircraft make and model is the one of the most flown globally.)[6] For approximately four seconds all hydraulics control was actually lost.[7][8]
US investigators?
What are you talking about?
This incident is investigated by India, France and Airbus:
https://en.wikipedia.org/wiki/Directorate_General_of_Civil_Aviation_(India)
https://en.wikipedia.org/wiki/Bureau_of_Enquiry_and_Analysis_for_Civil_Aviation_Safety
Oops. Read Boeing for Airbus for some reason. Carry on.
Hehe, it’s fine, I have done similar things