These safety devices, typically bright red fabric streamers with the cautionary text prominently displayed, serve a critical function in aviation. They act as warnings to ground crews, indicating components that need to be disconnected or deactivated before the aircraft takes flight. Examples include pitot tubes, control locks, and safety pins. Their removal signifies the aircraft’s readiness for takeoff.
The practice of using such indicators significantly reduces the risk of accidents caused by overlooked components that could impede flight. Historically, these safeguards evolved from simpler methods, becoming standardized for improved safety and communication across ground operations. This evolution reflects the aviation industry’s ongoing commitment to minimizing risks and ensuring safe flight operations.