What does FDR FAIL mean?

The term "FDR FAIL" refers to a failure detected within the Flight Data Recorder System (IDARS). In the aviation context, this indicates that the Flight Data Acquisition and Recording System, which is crucial for monitoring flight parameters and maintaining records of flight data for safety purposes, is not functioning properly. When this failure occurs, it is essential to notify maintenance to have them investigate and rectify the issue.

Understanding this concept is vital because the Flight Data Recorder plays a significant role in both routine monitoring and accident investigation. If this system fails, it can hinder the information available for assessing the aircraft's operational status and performance during flight, which is critical for both safety and compliance with aviation standards.

While the other options refer to different aircraft systems and potential issues, they do not specifically pertain to the "FDR FAIL" indication, which is why option A is the most appropriate answer for this question.