What is the de-ice cycle for the opposite blades?

The correct de-ice cycle for the opposite blades is indeed characterized by a "45 seconds on, 90 off" pattern. This timing is crucial for ensuring the effective removal of ice buildup on the rotor blades during flight operations in icing conditions.

The "on" portion of the cycle allows electrical heating elements to warm the blades sufficiently to melt any ice that may have formed. This is vital for maintaining optimal aerodynamic performance and ensuring the safety of the aircraft. The "off" portion allows for a brief cooldown period, which helps to prevent overheating of the de-icing system and components, and can also initiate icing in conditions that require the system to actuate again shortly thereafter.

Understanding the specifics of the de-ice cycle for opposite blades is essential for pilots and maintenance personnel, as improper cycles could lead to insufficient de-icing performance or potential damage to the aircraft systems.