What is the purpose of the standard run-up check prior to takeoff?

• A. To verify engine operability, pressure readings, fuel flow, and thrust control before takeoff.
• B. To recalibrate navigation and flight path alignment with ground stations.
• C. To confirm cabin pressurization is set for takeoff.
• D. To test landing gear retraction.

Answer: (A)

Before takeoff, a run-up check is done to ensure the engines and their critical supporting systems are healthy and prepared for full power. By advancing to the takeoff power setting and monitoring how the engines respond, pilots verify that there are no abnormal indications and that essential readings stay within limits. This includes checking that engine operability is normal, pressure readings (like oil or hydraulic pressures) are within spec, fuel flow behaves as expected, and the thrust controls respond smoothly and predictably. Detecting any deviations or warnings before committing to the takeoff helps prevent surprises at high speed.

The other tasks described—recalibrating navigation, confirming cabin pressurization settings, or testing landing gear retraction—are handled in different checks or phases and are not the primary purpose of the run-up.