The Acoustic Anomaly: Was the RAT Already Deployed?

In this episode, we deconstruct the preliminary acoustic evidence surrounding the infamous cockpit exchange: “Why did you cut off?” — “I didn’t do it.”.

While media reports suggest the CVR audio needed to be “cleaned up” to identify these voices, this necessity for heavy post-processing reveals a critical forensic clue. It suggests investigators were forced to rely on the Cockpit Area Microphone (CAM) rather than the typically clear individual headset channels.

Key Analysis Points:• The Acoustic Deduction: Heavy background noise and the need for “cleanup” points to a recording dominated by the Area Mic (CAM).

• The Electrical Implication: A CAM-only recording signature is consistent with the aircraft operating on backup power or in an abnormal electrical configuration, such as the deployment of the Ram Air Turbine (RAT). Technical schematics of the Recorder Independent Power Supply (RIPS) confirm that in the event of usual power failure, the RIPS sends battery power specifically to the Flight Deck Area Mic and the Forward Flight Recorder.

• The Timeline Conflict: The simplistic timeline suggests a Flight Control System (FCS) cutoff led to power loss and subsequent RAT deployment. However, if the audio recording of the voices already exhibits the “heavy noise” signature of backup power, the aircraft may have been in the RAT/backup configuration before the verbal exchange occurred.This evidence challenges the linear sequence of events and raises physics-based questions about the latency between control inputs and hydraulic pressure changes.

Sources:• Acoustic Evidence and the RAT Deployment Timeline• Acoustic_Forensics_Timeline_Revision• Flight Recorder System Schematics (RIPS/EAFR)