What is the purpose of an engine run-up?

The purpose of an engine run-up is to check the engine performance and systems before takeoff. This critical pre-flight procedure involves running the engine at specific RPMs while the aircraft is stationary, allowing the pilot to observe how the engine responds under load. During this check, various systems, such as magnetos, fuel flow, and other engine parameters, are tested to ensure they are functioning correctly. Identifying any potential issues at this stage helps ensure safety during flight, as it allows pilots to confirm that the engine operates properly prior to departure. This procedure is essential for preventing in-flight engine failures, making it a vital part of the pre-flight checklist.