What is the appropriate speed to fly during descent through moderate turbulence at FL280?

When flying through moderate turbulence, particularly at Flight Level 280, selecting the appropriate speed is critical for both safety and comfort. The recommended speed of 270 knots or Mach 0.76 is optimal for descent in these conditions. This speed is below the structural and maneuvering limitations of the aircraft, allowing for better control and reducing the risk of exceeding airspeed limits during turbulence.

Flying at 270 knots aids in maintaining an efficient descent rate while also mitigating aerodynamic loads on the airframe, which is a key consideration when experiencing turbulence. This speed strikes a balance between maneuverability and safety; it is fast enough to ensure a smooth operation without risking substantial stress on the aircraft structure.

In contrast, higher speeds, such as 300 knots or Mach 0.80, could lead to increased airframe stress and potentially exceed safe operating limits in turbulence, while slower options like 250 knots or 220 knots may not be efficient for descent, especially in maintaining adequate control and comfort in moderate turbulence.