What does delta P measure on the alternate engine data display?

Delta P measures the difference between cockpit pressure and ambient pressure on the alternate engine data display. This measurement is crucial as it allows pilots to understand the pressure differential, which can affect engine performance, safety, and cockpit environment. Variations in cockpit pressure relative to the external atmosphere provide significant insights into the operational status of the aircraft. Monitoring this difference helps ensure that the cockpit is adequately pressurized, which is essential for maintaining comfortable and safe conditions during flight, particularly in high-altitude operations. This understanding is key for pilots to respond to potential issues related to pressurization and overall safety during flight operations.