Which speed pair describes High Speed Descent Speed?

Which speed pair describes High Speed Descent Speed?

• A. .77 Mach or 320 Knots
• B. .74 Mach or 290 Knots
• C. 320 Knots or .70 Mach
• D. .70 Mach or 250 Knots

Answer: (A)

High Speed Descent Speed is the target range used to descend efficiently while staying within speed limits. For the CRJ-550, that range is defined as Mach 0.77 or 320 knots, whichever limit is reached first as you descend. At higher altitudes you stay with Mach 0.77 for efficiency; as you descend and the corresponding indicated airspeed would exceed 320 knots, you cap at 320 knots to avoid overspeed. This dual specification lets the airplane descend quickly without breaking speed restrictions. The other options don’t represent the standard HSDS pairing, which is why the Mach 0.77 / 320 knots choice is the correct one.

High Speed Descent Speed is the target range used to descend efficiently while staying within speed limits. For the CRJ-550, that range is defined as Mach 0.77 or 320 knots, whichever limit is reached first as you descend. At higher altitudes you stay with Mach 0.77 for efficiency; as you descend and the corresponding indicated airspeed would exceed 320 knots, you cap at 320 knots to avoid overspeed. This dual specification lets the airplane descend quickly without breaking speed restrictions. The other options don’t represent the standard HSDS pairing, which is why the Mach 0.77 / 320 knots choice is the correct one.