Circling Minima

Definition

Circling minima refer to the lowest altitudes and visibility requirements a pilot must meet to safely conduct a circling approach—a maneuver used when the instrument approach leads to a runway different from the one in use. These minima ensure the aircraft remains clear of obstacles while visually maneuvering to land after completing an instrument approach. Circling minima are published for each approach procedure and vary based on aircraft category (A–D), which reflects approach speed.

Purpose

  • Provide protected obstacle clearance during visual maneuvering
  • Allow pilots to circle to a more suitable runway after flying an instrument approach
  • Ensure that the aircraft remains within a defined protected area at all times

Circling Approach in Brief

  • Flown visually, after completing an instrument approach
  • Used when wind, runway availability, or terrain requires landing on a different runway
  • Requires the pilot to maintain visual contact with the runway environment
  • Must remain within the circling area for their aircraft category

Standard Circling Radii (ICAO/PANS-OPS)

Category Approach Speed (KIAS) Radius from RWY Threshold
A ≤ 90 ~1.68 NM
B 91–120 ~2.66 NM
C 121–140 ~3.28 NM
D 141–165 ~4.20 NM

Note: Actual protected radii may vary with elevation and procedure design standards (e.g., TERPS vs. PANS-OPS).

Circling Minima Components

Element Definition
Minimum Descent Altitude (MDA) Lowest permitted altitude (MSL) for maneuvering
Obstacle Clearance Height (OCH) Vertical distance above runway threshold or airport elevation
Visibility Required to maintain constant sight of the runway environment

Example (approach chart):
Circling Minima (Cat B): MDA 1600 ft, OCH 550 ft, visibility 2.4 km

Conditions to Continue Below MDA

  • ✅ Runway or its environment is in sight
  • ✅ Aircraft can be safely maneuvered to final approach
  • ✅ Aircraft remains within circling area
  • ❌ If visual contact is lost, immediate missed approach must be initiated

Missed Approach in a Circling Approach

  • If missed approach is needed:
  • Turn toward the landing runway
  • Then climb and intercept the published missed approach path
  • May require maneuvering back toward the initial approach runway

Phraseology Examples

  • “Runway in sight, commencing circling to runway 09.”
  • “Maintaining circling minima, visual.”
  • “Lost visual contact during circling, going around.”

Tips for Pilots

  • ✅ Always brief MDA, visibility, and terrain around the airport
  • ✅ Remain within the correct radius for your category
  • ✅ Maintain a clear view of the runway at all times
  • ✅ Use LearnATC to practice circling scenarios with realistic weather and terrain