The airspeed limitation for severe turbulence penetration is whichever is lower.

The airspeed limitation for severe turbulence penetration is whichever is lower.

• A. 280 Knots or 0.75 Mach, Whichever is Lower
• B. 300 Knots or 0.80 Mach
• C. 260 Knots or 0.70 Mach
• D. 290 Knots or 0.90 Mach

Answer: (A)

In severe turbulence penetration, you want to protect the airframe from excessive loads while still keeping the handling predictable. The guidance is to fly at the lower of two references: an indicated airspeed of 280 knots or Mach number 0.75. This ensures you stay within safe dynamic-pressure limits at lower altitudes (where IAS is the controlling factor) and within speed-of-sound related limits at higher altitudes (where Mach becomes the controlling factor). Because one of these two limits will be more restrictive depending on your altitude, taking the lower value provides the safest, most controllable penetration through turbulent air.

In severe turbulence penetration, you want to protect the airframe from excessive loads while still keeping the handling predictable. The guidance is to fly at the lower of two references: an indicated airspeed of 280 knots or Mach number 0.75. This ensures you stay within safe dynamic-pressure limits at lower altitudes (where IAS is the controlling factor) and within speed-of-sound related limits at higher altitudes (where Mach becomes the controlling factor). Because one of these two limits will be more restrictive depending on your altitude, taking the lower value provides the safest, most controllable penetration through turbulent air.