Stable Approach Criteria

Question 1

What is the SAC? (5)

Answer 1

Must be stable by the 1000ft auto-callout

• In the planned landing configuration
• Stabilised on the correct vertical and lateral profile
• Stabilised at the target approach speed

In all cases the checklist must be completed by the 500ft auto-callout

Question 2

How is the vertical and lateral profile defined for the SAC? (3)

Answer 2

• A 3D Instrument approach or
• A 2D final approach path/track or
• A visual profile, which may include FMS guidance

Question 3

When can the “Speed” call be made at 1000’ radio? (5)

Answer 3

In the case of

• rapid wind changes;
• turbulence;
• or adherence to appropriate ATC speed requirements

Where the speed stability has not been achieved by the 1000ft auto-callout and speed is no more than 20kts above target approach speed and reducing.

If the aircraft is not stable at the target approach speed before the 500ft auto-callout then a go-around must be flown.

Question 4

How do you define a visual profile in the SAC? (3)

Answer 4

The method of defining the correct visual profile should be agreed at the briefing stage. The correct visual profile is that defined by either:

• A Visual Approach Slope Indicator System (VASIS), if available. Once established on the extended centreline an indication of “All Whites” or “All Reds” would not satisfy the stabilised approach criteria or;
• Where no VASIS guidance is provided the required profile will default to that commensurate with a 3° approach slope.