The N3 Indicator is an important gauge found in the cockpit of aircraft equipped with three-spool jet engines, like the Rolls Royce RB211. This gauge shows the rotational speed of the high-pressure engine spool, commonly referred to as N3. Typically, the N3 Indicator displays values in percent RPM, where 100% corresponds to a specific rotational speed defined by the engine manufacturer.
You may find the N3 Indicator as either a standalone analogue or digital gauge. Alternatively, this information can be integrated into systems like the Engine Indicating and Crew Alerting System (EICAS) or the Electronic Centralized Aircraft Monitor (ECAM) if those systems are installed in the aircraft. Understanding the N3 Indicator is crucial for pilots, as it helps monitor engine performance and ensures safe flight operations.
