Arc Approach

Introduction:

  • An arcing approach is a type of instrument approach where the aircraft flies a set radius around the NAVAID in order to intercept a final approach course inbound

Arc Methods:

  • Fly the arc via GPS:
    • Simply follow the indications on the GPS
  • Fly 10, twist 10:
    • Once established on the arc, twist the HSI 10 degrees off (in direction of turn-twist left, turn left or twist right, turn right)
    • Fly until HSI centers then turn 10 degrees along the arc and twist another 10 degrees
    • Continue doing this until you reach the lead turn radial to turn on the final approach course
    • Essentially, the pilot is turning the arc into segments

Arc Approach Procedure:

WARNING:
All procedures are GENERALIZED.
Always fly per Pilot Operating Handbook procedures,
observing any relevant Standard Operating Procedures (SOPs)


  1. Listen to ATIS or tower for landing runways and possible equipment outages
  2. Request approach from Air Traffic Control
  3. Tune and identify the NAVAID and DME, as appropriate
  4. Verify that the HI or HSI is aligned with the magnetic compass
  5. Fly ATC instructions, which will be vectors for final (skip ahead) or vectors for the initial approach fix (IAF)
    • Looking at the ILS/LOC 7L, you will proceed to HANAV if from the north or MIKBE if from the south
  6. Review the approach plate and give an approach brief
  7. Determine whether to join the arc with a left or right turn
  8. Join the arc by anticipating turn radius
    • Intercepting the arc from a radial (90°), use 0.5-1% of the ground speed
    • If intercepting at less than an 90° degree angle, use less lead
    • Comply with all altitude restrictions
  9. Note the distance after the turn is completed:
    • If the DME is 0.1 greater than the arc, turn 10° toward the arc
    • If the DME is 0.1 less than the arc, maintain your current heading until the DME increases to the assigned DME distance, then turn 10deg; toward the arc
  10. To help maintain positional orientation and situational awareness, use the OBS to determine your position along the arc
  11. Complete the descent flow/checklists
  12. Fly the arc until your lead radial for the final approach course
    • Lead radial is determined using your arc distance and Ground Speed (GS):
      • 60 ÷ Arc Distance x 1% of GS
      • Example: If the arc is 16 NM, flying at 80 knots ground speed:
        • 60 ÷ 16 x .8 = 3 radials
  13. Join the final approach course and center up the CDI
    • Comply with all altitude restrictions
  14. At the Final Approach Fix (FAF), report:
    • "[Facility-Tower], [Callsign], final approach fix, gear 3 down and locked"
  15. Descend to Minimum Descent Altitude (MDA), complying with altitude restrictions
  16. At the missed approach point, execute the missed approach instructions
ILS 7L KDAB
ILS or LOC 7L KDAB Arcing Approach

Airman Certification Standards:

Conclusion:


References: