Airbus vs Boeing: Engine Start Philosophy Isn’t the Same On the A320, starting an engine is as simple as flipping the MODE selector to IGN/START and turning the ENG knob to 1 or 2. The rest—fuel, air, ignition—is handled automatically by the FADEC system. No need to monitor N2 or manually introduce fuel. It’s fire-and-forget. The 737, however, keeps the pilot in the loop. You monitor N2 rise, flip the fuel lever at the right time, and listen for the distinctive whine as the engine spools up. It’