This lesson provides an overview of DME arcs and how to fly them in a Robinson R44 IFR trainer equipped with a Garmin 430W GPS.

Student Preparation

Reading Assignments

Sample Ground Questions

  • Examine the COPTER ILS OR LOC/DME RWY 23 plate at KFMH. Why is the 069 radial explicitly marked “LR-069”? If it were a 10NM DME arc, would you expect this to be closer or farther away from the approach course radial? Why?
  • In what situations may a DME arc be convenient (e.g., save time)?

Flight Elements

  • Depart westbound from KBED off simulated RV (e.g., depart heading 270, climb maintain 2500).
  • Instructor simulates clearance to intercept and track V431 westbound towards GDM.
  • Intercept and turn northbound to fly a 10NM DME arc.
  • Stay on the arc until flown within 0.2 NM for consecutive turns or for at least 3 turns of the OBS.
  • Intercept a turn inbound towards the GDM VOR.
  • Start preparing for the VOR-A approach at KGDM with a simulated DME arc entry.
  • At the VOR, turn and fly the 240 radial outbound.
  • Off the outbound course, intercept the 10NM arc and turn northbound (simulated DME arc as an IAF).
  • Turn inbound 097 to intercept the final approach course (see the approach plate).
  • Land at GDM or go missed as appropriate.
  • Airwork enroute back to KBED followed by a GPS 23 or ILS 29 at KBED full-stop.


  • Book a Robinson R44 IFR trainer (e.g., N171WT)
  • Current approach plates
  • Low Altitude Enroute Chart
  • Instrument hood

Completion Standards

Student will answer all ground questions correctly and review any questions for which there are problems with an instructor, demonstrating an understanding of DME arc fundamentals.


Many thanks to Rudy Perini, with whom this was originally developed.