Calibrated, in instrument terminology, means what?

• A. The instrument indication compared with a standard value to determine the accuracy.
• B. The instrument's displayed speed under normal operation.
• C. The calibration date of the instrument.
• D. The maximum safe operating limit of the instrument.

Answer: (A)

Calibration means the instrument’s indication is compared with a known standard value to determine its accuracy. In practice, this involves checking the reading against a reference and making adjustments so the instrument reads correctly within allowable tolerances across its operating range. This ensures you can trust the readings for safe flight decisions. The other ideas don’t fit because the displayed speed during normal operation is just a readout, not a validation of accuracy; the calibration date is simply when calibration happened, not what calibration means; and the maximum safe operating limit is about constraints, not the accuracy of the indication.