When crossing the critical Mach threshold, which effect is a known compressibility consequence?

When crossing the critical Mach threshold, which effect is a known compressibility consequence?

• A. Decreased Drag
• B. Drag Increases
• C. Improved Turn Coordination
• D. Consistent Instrument Readings

Answer: (B)

When you reach and pass the critical Mach threshold, compressibility effects show up as a rise in drag due to wave drag from shock waves forming on the wing and other surfaces. As parts of the flow locally reach Mach 1, shocks appear, disturbing smooth pressure recovery and converting some of the flow’s kinetic energy into additional pressure forces, which increases overall drag. This rapid drag increase is the hallmark compressibility consequence in the transonic regime. The other options don’t fit: drag doesn’t decrease, transonic flow isn’t about improving turn coordination, and while instrument readings can become less predictable near these speeds, the primary compressibility effect described by crossing the threshold is the increase in drag.

When you reach and pass the critical Mach threshold, compressibility effects show up as a rise in drag due to wave drag from shock waves forming on the wing and other surfaces. As parts of the flow locally reach Mach 1, shocks appear, disturbing smooth pressure recovery and converting some of the flow’s kinetic energy into additional pressure forces, which increases overall drag. This rapid drag increase is the hallmark compressibility consequence in the transonic regime. The other options don’t fit: drag doesn’t decrease, transonic flow isn’t about improving turn coordination, and while instrument readings can become less predictable near these speeds, the primary compressibility effect described by crossing the threshold is the increase in drag.