Which component provides airspeed, altitude, and vertical speed data to the PFD?

• A. Attitude and Heading Reference System
• B. Inertial Reference System
• C. Air Data Computer
• D. Flight Management System

Answer: (C)

Airspeed, altitude, and vertical speed data for the PFD come from the Air Data Computer. The ADC processes inputs from the pitot tube and static ports, converting dynamic pressure into indicated airspeed, and static pressure into altitude and the rate of altitude change (vertical speed). It may also compute derived values like Mach. The Attitude and Heading Reference System provides attitude and heading data, not air data. The Inertial Reference System supplies inertial data for attitude and velocity, but not air pressure-based data. The Flight Management System handles navigation and performance planning, not the raw air data shown on the PFD.