Which of the following is a requirement for starting the engine?

For starting the engine, it's essential that the Interstage Turbine Temperature (ITT) is below 150 degrees Celsius. This requirement ensures that the engine starts safely and prevents thermal stress or damage. If the ITT is above this threshold at the time of engine start, it could lead to excessive temperatures during the ignition and combustion process, potentially resulting in engine damage or failure to start.

While the state of other systems, such as battery voltage, Ng (N1 or gas producer speed), and the condition lever position, are important for engine operation and performance, they are not strict prerequisites for initiating the engine start sequence. Maintaining an ITT below 150 degrees Celsius is thus a critical factor and an established standard in engine operation procedures to ensure reliability and safety during the starting process.