Which of the following activities is NOT included in critical phases of flight?

The activity that is not considered part of the critical phases of flight is ascent. Critical phases of flight generally refer to specific periods where the pilot's attention needs to be sharply focused due to increased risk and the potential for accidents. These phases usually include takeoff, landing, and taxiing because they involve significant changes in aircraft dynamics or proximity to the ground, which can present unique challenges.

During takeoff and landing, pilots must navigate various factors such as runway conditions, weight and balance considerations, and environmental conditions like wind and visibility. Taxiing also requires heightened attention due to the presence of ground personnel, other aircraft, and potential obstacles on the airport surface.

In contrast, ascent, while important, is typically a phase that has more stable conditions compared to the immediate risks present during takeoff and landing. During ascent, pilots are usually in the process of gaining altitude and can rely more on automated systems and the aircraft's established performance capabilities without the same level of immediate hazards found in the critical phases.