NewStart →
← Lesson plans

Instrument rating · ACS IR.V.A · Instructor lesson plan

Intercepting and Tracking Courses and DME Arcs

Student pack: Train: Intercepting and Tracking Courses and DME Arcs · Full lesson: Prepare guide

Instructors: sign in to edit and approve your own version.

1 · Objective

By the end of this lesson your student can explain intercepting and tracking courses and dme arcs in their own words, apply it in a realistic situation, and fly it to the ACS standard for IR.V.A.

Why it matters for safety: Navigation errors in IFR put airplanes off the protected airspace that keeps them clear of terrain. A wrongly tuned station, a reversed needle, or a GPS flight plan that wasn’t checked all look fine until they don’t. Knowing your position and verifying your equipment is what turns navigation from following a needle into knowing where you are.

2 · Assign before the lesson

Pre-work: the free Train pack, Intercepting and Tracking Courses and DME Arcs. VOR, GPS and DME arcs: know where you are, intercept cleanly, and track with wind.

Anyone can open this link, no account needed. To see who trained it on your roster, use a free instructor account.

Pack: pilotprep.pro/train/ifr/intercepting-and-tracking-navigational-systems-and-dme-arcs · Full lesson: pilotprep.pro/prepare/ifr/intercepting-and-tracking-navigational-systems-and-dme-arcs

3 · Teach sequence

Key points to land

  • Tune and identify every ground navaid by its Morse code. No identifier means don’t use it.(AIM, Chapter 1 (navigation aids, GPS and WAAS))
  • Before intercepting, know where you are relative to the station or waypoint: which radial, which side, how far.(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • Intercept angle: usually 30° to 45°; up to 90° when far off course; less close to the station, and no more than about 30° onto a localizer. Lead the rollout as the needle starts to center.(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • Track by bracketing: find a heading that holds the needle centered, then make smaller corrections.(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • DME arc: turn onto it about ½ nm early at groundspeeds of 150 knots or less (more lead when faster), keep the bearing near the wingtip with small heading changes, and leave it on the lead radial.(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • GPS: verify the flight plan, the database, the CDI source, the active leg and the mode annunciation. Non-WAAS units need a RAIM prediction; watch for integrity alerts and GPS interference NOTAMs.(AIM, Chapter 1 (navigation aids, GPS and WAAS))
  • Checkride standard: course within ¾-scale CDI, DME arc ±1 nautical mile, altitude ±100 feet, heading ±5°.(Instrument Rating ACS (FAA-S-ACS-8C), IR.V.A.S5-S6)

Ground-based navigation

  • Set the course, check TO/FROM, and orient: with the course set close to your heading, the needle points toward the course.(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • Reverse sensing: flying a VOR course with the opposite TO/FROM (or a localizer back course on a CDI) makes the needle work backward. An HSI set to the front course avoids it.(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • DME is slant range: at least 1 mile from the station per 1,000 feet of altitude, the error is negligible.(AIM, Chapter 1 (navigation aids, GPS and WAAS))
  • DME arc with an RMI: keep the bearing pointer cycling between about 5° and 10° behind and ahead of the wingtip; if you drift ½ nm off the arc, correct 10° to 20° toward it. Wind changes how often. Leave the arc at the lead radial (charted, or a few degrees early at 150 knots or less).(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • Station passage: approaching a VOR the needle gets more sensitive, then the cone of confusion makes it swing and the TO/FROM flips. A GPS shows passage when it sequences to the next leg.(Instrument Flying Handbook (FAA-H-8083-15B), Navigation Systems)
  • For IFR, the VOR must have been checked within the preceding 30 days: ±4° on a VOT or ground checkpoint, ±6° airborne, 4° between two receivers; logged with the date, place, bearing error and signature.(14 CFR 91.171)
  • Many VORs are being shut down; a minimum operational network (MON) of VORs remains. Check NOTAMs for outages.(AIM, Chapter 1 (navigation aids, GPS and WAAS))

Satellite navigation

  • GPS for IFR must be installed and approved, with a current database for approaches.(AIM, Chapter 1 (navigation aids, GPS and WAAS))
  • RAIM checks the satellites agree: fault detection needs 5 satellites (or 4 with baro-aiding), and fault exclusion 6 (or 5 with baro-aiding). A non-WAAS unit needs a preflight RAIM prediction, and an alternate means of navigation for the route. WAAS adds its own integrity monitoring. If integrity is lost in flight, tell ATC and use the other means.(AIM, Chapter 1 (navigation aids, GPS and WAAS))
  • GPS can be jammed or spoofed. Watch for NOTAMs and integrity alerts, and keep a ground-based backup when you can.(AIM, Chapter 1 (navigation aids, GPS and WAAS))
  • GPS CDI full scale: ±2 nm en route (±5 nm on older non-WAAS units), ±1 nm in the terminal area within 30 nm of the airport, ramping to ±0.3 nm (or angular) from 2 nm before the final approach waypoint. Manually changing the sensitivity can cancel approach mode.(AIM, Chapter 1 (navigation aids, GPS and WAAS))

Managing the box

  • Check the active waypoint, the course and the CDI source (GPS or VLOC) after every change. Use the MFD map to confirm where the navigator thinks you are.(Advanced Avionics Handbook (FAA-H-8083-6))
  • With the autopilot: select the nav mode, confirm it is armed and then captures (active) on the annunciator, and watch the first intercept; if it doesn't do what you expect, fly heading mode or hand-fly.(Advanced Avionics Handbook (FAA-H-8083-6))
  • If programming takes your eyes off the instruments too long, fly a heading first, then program.(Advanced Avionics Handbook (FAA-H-8083-6))
  • If a navaid or GPS fails, tell ATC.(Instrument Rating ACS (FAA-S-ACS-8C), IR.V.A.S7)

Watch for in the airplane: Your instructor watches for tuning and identifying every time, a correct picture of your position, a clean intercept, wind correction, and the right CDI source.

4 · Ask your student

In order: recall, then understanding, then applying it. Move up only when the answer shows it.

  1. Recall · What is a typical intercept angle?

    A strong answer: 30 to 45 degrees, up to 90 when far off, less when close to the station, and no more than about 30 onto a localizer.

  2. Understand · Why does DME read more than your ground distance when you’re over the station?

    A strong answer: It measures slant range: the straight line to the station, which includes my height. Overhead, it shows my altitude in nautical miles.

  3. Apply · Your GPS shows an integrity alert halfway to your destination. What do you do?

    A strong answer: Tell ATC, cross-check with VOR or ask for vectors, and don’t use the GPS for an approach until the alert clears.

Scenarios to talk through

  • Flying a VOR course, the needle moves the opposite way to your correction. What’s wrong?

    Sound decision: Probably reverse sensing: TO/FROM doesn’t match my direction. Reset the course to match where I’m going.

  • Your CDI is centered, but you’re far from where the map shows you should be. What do you check?

    Sound decision: The CDI source (GPS vs VLOC), the active waypoint, and whether the navaid is identified.

  • On a 10 DME arc with a crosswind pushing you toward the station. What do you expect?

    Sound decision: I’ll need fewer turns toward the station and may need to turn away. Keep it within ±1 mile.

5 · Common student errors

  • Not identifying the station.

    Why it matters: It may be off the air or a different station.

    How to correct it: Listen to the Morse code.

  • Wrong CDI source.

    Why it matters: You follow the wrong needle.

    How to correct it: Check GPS or VLOC every time.

  • Chasing the needle.

    Why it matters: You zigzag.

    How to correct it: Find a heading, then bracket.

6 · Completion standard

  • Maintain airspeed ±10 knots, altitude ±100 feet, and selected headings ±5°.
  • Maintain a course with no more than ¾-scale CDI deflection; on a DME arc, maintain the arc ±1 nautical mile.
  • Your student answers each "Ask your student" question in their own words, up to the Apply level, without prompting.
  • They talk through the scenarios and reach a safe, legal decision, explaining why.
  • They complete the pack’s quick check and can say what they flagged.

Area trained? Close out with a practice oral focused on IR.V.A: pilotprep.pro/exam?exam=IFR&focus=IR.V.A

7 · References

  • Instrument Flying Handbook (FAA-H-8083-15B), Navigation systems
  • Instrument Procedures Handbook (FAA-H-8083-16B), Departures; en route; arrivals
  • Aeronautical Information Manual (AIM), Chapters 1, 4, 5 and 7
  • Instrument Rating ACS (FAA-S-ACS-8C), Area V
  • Airman Certification Standards, task IR.V.A

PilotPrep instructor lesson plan, from the Intercepting and Tracking Courses and DME Arcs lesson (checked against current FAA sources 2026-11-13). A study and teaching aid, not FAA guidance; teach to your own judgment and the current ACS.