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6.2 ILS Approach

6.2.1 General

The Instrument Landing System (ILS) is a precision approach providing lateral and vertical guidance to the runway.

The Approach Controller shall position aircraft to intercept and track the ILS in a stable and controlled manner.

6.2.2 Components

The ILS provides:

  • Localiser – lateral guidance
  • Glide slope – vertical guidance

6.2.3 Controller Responsibilities

The Approach Controller shall:

  • Vector aircraft onto the localiser
  • Ensure an appropriate intercept angle (typically 20°–30°)
  • Position aircraft to intercept the localiser prior to glide slope intercept
  • Ensure adequate spacing between aircraft
  • Deliver aircraft in a stable configuration

6.2.4 Intercept Requirements

The Approach Controller shall:

  • Issue final vector at an appropriate distance from the localiser
  • Ensure aircraft can capture the localiser smoothly
  • Avoid excessive intercept angles
  • Ensure aircraft are established on the localiser before glide slope intercept

Intercept shall be planned to avoid late corrections.

6.2.5 Approach Clearance

The Approach Controller shall issue ILS approach clearance only when:

  • The aircraft is correctly positioned for the approach
  • Separation with preceding traffic is assured
  • The aircraft can intercept and maintain the approach

The aircraft should normally be established on the localiser prior to glide slope intercept when clearance is issued.

6.2.6 Sequencing and Spacing

The Approach Controller shall:

  • Achieve required spacing prior to final approach
  • Prevent compression of traffic on the localiser
  • Use speed control and vectoring to maintain spacing

Spacing shall not rely on late corrective action.

6.2.7 Stability Considerations

The Approach Controller shall ensure that:

  • Aircraft are established on the localiser with minimal correction
  • Aircraft can intercept the glide slope from below
  • Speed and descent profile support a stable approach

Unstable approaches shall be corrected early or a go-around shall be expected or instructed.

6.2.8 Limitations

The Approach Controller shall not:

  • Issue late or excessive turns onto final
  • Vector aircraft through the localiser
  • Allow aircraft to intercept the glide slope from above
  • Transfer aircraft in unstable or compressed conditions

6.2.9 Example Flow

  1. Aircraft established on downwind
  2. Base turn issued
  3. Final vector provided
  4. Aircraft captures localiser
  5. ILS approach clearance issued
  6. Aircraft intercepts glide slope
  7. Transfer to Tower

6.2.10 Key Principle

ILS approaches shall be stable, predictable, and correctly spaced.

The Approach Controller shall:

  • Plan ahead
  • Position accurately
  • Deliver stable approaches

A correct setup results in minimal pilot correction and safe approach completion.

  • Avoid high intercept angles
  • Ensure aircraft is below glide slope when intercepting
  • Maintain stable spacing