A320 | Sierra Pattern

The Sierra Pattern is not a specific "mode" like CLB or DES, but a specific geometric path computed by the Flight Management System (FMS). It is used to manage energy and altitude during Confined Area Approaches, Continuous Descent Final Approaches (CDFA) with step-down fixes, or for Noise Abatement procedures.

Trap 3: Late Flap Extension

  • Problem: The Sierra level segment is at 10,000ft, but you need to extend flaps to slow to 180kts.
  • Result: You extend flaps during the level segment, causing drag. The FMS compensates with more thrust, then struggles to descend later.
  • Fix: Complete flap extension before the Sierra segment or after the exit descent begins, not during the level segment.
  • Inspect flight data / navigation chart
  • Use recordings/flight path imagery

    What is a Sierra pattern?

    • Example: If landing on Runway 27 (heading west), you turn Right to a heading of 300° (a 30° offset).
    • Why 30 degrees? This creates a safe lateral offset. You are climbing away from the extended centerline, clearing the way for the aircraft behind you.
    • Clean-up: At Acceleration Altitude, select Flaps UP (Flap lever to 0). The speed will transition from Vapp (approach speed) to Green Dot speed (engine-out climb speed).