Which indication is NOT part of the engine performance section of the EICAS display?

• A. Fuel flow
• B. Gas turbine speed (% N1)
• C. Interstage turbine temperature (C ITT)
• D. % Torque

Answer: (A)

The engine performance section on EICAS focuses on real-time operating states that directly reflect how the engine is producing thrust: the gas turbine speed, the temperature within the turbine, and the engine’s torque output. Gas turbine speed, shown as a percentage of N1, tells you how fast the compressor and turbine are rotating and how much core power is available. Interstage turbine temperature (ITT) indicates how hot the turbine section is running, which is a direct limit and health indicator for the engine. The percent torque shows the engine’s current thrust-producing capability.

Fuel flow, on the other hand, measures how much fuel is being consumed. That parameter is more about fuel management and consumption, typically found on the fuel or engine fuel pages rather than within the engine performance block. It doesn’t directly indicate the instantaneous operating state of the engine’s speed, temperature, or output, which is why it isn’t considered part of the engine performance section.

So, fuel flow is the indicator that isn’t part of the engine performance section. The other three—N1, ITT, and torque—are the performance indicators.