Brandon Martini, COO
Performing a proper aircraft run-up is a fundamental step in pre-flight procedures, ensuring that an aircraft is functioning correctly before takeoff. This crucial process allows pilots to detect potential mechanical issues, verify system performance, and confirm that the aircraft is safe for flight. Skipping or rushing through a run-up can lead to serious consequences, making it an essential practice for pilots at every experience level.
Understanding the Run-Up Process
A run-up is conducted after taxiing but before takeoff, typically in a designated area at the airfield. This process involves checking engine performance, control systems, and various instruments to ensure everything is operating as expected. While the specifics may vary between aircraft types, the fundamental goal remains the same: to catch any potential issues before they become airborne problems.
Key Elements of a Run-Up
1. Engine Performance Checks
Testing engine function is the most critical aspect of a run-up. Pilots increase the throttle to a specified RPM and observe engine behavior, listening for unusual noises and monitoring for any irregularities in fuel flow, oil pressure, and cylinder head temperatures.
2. Magneto Checks
Ensuring proper ignition system function requires testing each magneto individually. An acceptable RPM drop when switching between magnetos indicates they are working correctly, while an excessive drop may signal an issue requiring maintenance.
3. Flight Controls and Instruments
Pilots verify that control surfaces move freely and respond correctly, ensuring proper maneuverability. Additionally, they check flight instruments such as the attitude indicator, heading indicator, and altimeter for accuracy.
4. Propeller Functionality (If Applicable)
In aircraft with variable-pitch propellers, the run-up includes cycling the propeller to ensure proper oil distribution and pitch adjustment.
5. Vacuum and Electrical Systems
The vacuum system, which powers certain flight instruments, is checked to confirm it is within operational limits. Similarly, electrical systems, including radios and lights, are tested to ensure they are functioning properly.
Run-Ups in Different Aircraft Types
• Single-Engine Aircraft: Most general aviation planes follow a standard run-up procedure that includes engine, magneto, and control checks.
• Multi-Engine Aircraft: Involves additional checks for multiple engines, including propeller feathering tests and synchronization between engines.
• Seaplanes: Since seaplanes do not have traditional run-up areas, the procedure is performed while taxiing on the water, requiring added attentiveness.
The Consequences of Skipping a Run-Up
Neglecting or improperly executing a run-up can result in critical failures during flight. Common issues that could be detected during a run-up include misfiring magnetos, engine roughness, incorrect fuel mixtures, or malfunctioning flight instruments. Catching these problems on the ground ensures they can be addressed before takeoff, significantly improving flight safety.
Best Practices for an Effective Run-Up
• Always use a checklist to ensure no step is overlooked.
• Conduct the run-up in a safe and designated area.
• Take the time to carefully observe engine behavior and instrument readings.
• If anything seems off, do not proceed with the flight until the issue is resolved.
A proper aircraft run-up is a crucial step in aviation safety, allowing pilots to verify the health of their aircraft before departure. By following a thorough and structured approach, pilots can identify and address potential problems before they become airborne emergencies. Whether flying a single-engine trainer or a complex multi-engine aircraft, a disciplined run-up procedure is a key habit of a responsible and skilled aviator.