Which de-icing method involves activating both pairs of blades at once?

The de-icing method that involves activating both pairs of blades at once is known as the opposite blades heating process. This method is effectively designed to ensure that ice accumulation is minimized on aircraft propeller blades by providing heat to both blades simultaneously. By heating opposite blades, it optimizes the de-icing process, as ice can be melted and prevented from building up on all sections of the blades, thereby maintaining aerodynamic efficiency and safety during flight.

The other methods, such as the boots activating sequence or the alternating de-ice method, operate on different principles or timings. The boots activating sequence typically involves a sequential activation of the de-icing boots, which may not provide the same comprehensive coverage as the opposite blades heating method. Similarly, the alternating de-ice method activates one pair of blades and then the other, rather than activating both pairs at the same time, which can lead to periods where some blades are not actively de-icing. Understanding these distinctions is important for effective aircraft operations in icy conditions.