Intercepting and Tracking Navigational Systems and DME Arcs

Objective: the student will be introduced to intercepting and tracking to VORS and GPS systems. The student will also be introduced to DME Arcs.

Completion Standards: the student will be able to explain the steps in to reconozing navigation systems as well as how to intercpt radials from a VOR and GPS. The student will be able to explain what a DME arc is and how it is flown.

References: IFH ch9, IPH

Equipment: White Board and markers, iPad/ computer 

IP’s Actions:

• Assess student

• State the objective and completion standards

• Writes down references

• Provide attention getter

• Present content

• Assessment

• Assign Homework

SP’s Actions:

• Take notes

• Ask Questions

Introduction: 

(Attention Getter) : (Link goes here)

Motivation: (Discuss purpose for lesson and relate to Attention getter)

Overview:

1. Tuning and identification of a navigational facility

2. Setting of a selected course on the navigation 

3. Method 

4. Procedure

5. Recognition of navigation 

6. DME Arcs

Content:

Tuning and identification of a navigational facility

VOR

1. Tune VOR receiver to frequency of appropriate VOR station selected from en route or IAP chart

2. Identify by Morse code signal and/or voice identification 

GPS

1. Check database current

2. Enter/check proper waypoint 

3. How to tune

Setting of a selected course on the navigation selector or the correct identification of a selected bearing on the RMI

1. Copy, read back clearance to confirm correct course radial and track direction (inbound or outbound)

   1. Airways

   2. Holds 

2. Dial OBS to set course index on correct course 

   1. Tracking outbound FROM station

      1. Radials

   2. Tracking inbound TO station

      1. Course / opposite radial

Method for determining aircraft position relative to a facility

1. Center CDI to determine radial

   1. Weather travelling to or from

      1. TO – course is to the station

      2. From – on a radial from station

Procedure for intercepting and maintaining a selected course.

VOR/ LOC(ILS)

1. Course interception 

   1. Fly parallel to and in same direction as desired course

      1. Determine difference between desired and current radials

   2. Rotate OBS to set desired course at index

      1. Double the difference to determine intercept angle between 20° and 90°

         1. L eft

         2. A DD

         3. R ight

         4. S ubtract

      2. Turn to intercept heading

      3. Fly until CDI centers

      4. Turn and track desired course inbound or outbound 

2. Course tracking (Full deflection 10deg)

   1. On intercept, first maintain same heading as desired course

      1. Note drift off course downwind

      2. Turn 20° into wind back toward course

   2. When CDI centers on course, reduce wind correction angle to 10° into wind

      1. Note any drift and adjust wind correction angle appropriately to regain and maintain on course with centered CDI

GPS (Not Flying Direct)

1. Course interception 

   1. Fly parallel to and in same direction as desired course

   2. Determine difference between desired and current radials

   3. Rotate OBS to set desired course at index

      1. Double the difference to determine intercept angle between 20° and 90° 

         1. L eft

         2. A DD

         3. R ight

         4. S Ubtract

      2. Turn to intercept heading

      3. Fly until CDI centers

      4. Turn and track desired course inbound or outbound 

2. Course tracking 

   1. On intercept, first maintain same heading as desired course

      1. Note drift off course downwind

      2. Turn 20° into wind back toward course

   2. When CDI centers on course, reduce wind correction angle to 10° into wind

      1. Note any drift and adjust wind correction angle appropriately to regain and maintain on course with centered CDI

Recognition of navigation receiver or facility failure

VOR

• Morse code absent

• VOR receiver FLAG(signal strength inadequate)

  • VOR inop

  • VOR too far away

  • Airplane too low

• Erratic CDI movements

  • VOR too far away

  • Receiver malfunction

GPS

• Text message or signal if GPS position becomes available

  • LOI

Common Errors

• Incorrect tuning and identification procedures

  • Check correct facility

  • Correct frequency

  • Correct radio

  • Correct morse code / voice ID

• Failure to set the navigation selector on the course to be intercepted

  • Tracking to or from station?

DME Arcs

Overview

DME Arcs are most commonly found on Instrument Approaches. A DME Arc is a way to fly a constant distance arc around a navigation system

How to establish

• Each DME Arc will be defined by a radial from the navigation station

  • KDAB ILS 7L

• Is executed by flying short, straight segments around the arc

  • at a certain distance (DME)

• Heading into the turn

  • Initial heading will be the same regardless of where the pilot joins the arc

  • A pilot should begin the turn to the initial heading at ½ his/her groundspeed prior to reaching the desired DME

    • 100 KIAS, this would mean the pilot would begin the turn 0.5 NM prior to the desired DME

Maintaining distance in arc

• intercept each 10 degrees of radial at a 90 degree angle

  • “Turn 10, Twist 10.”

• Crosswinds

  • Adjusting  to drift

    • DRAW IT OUT

Common Errors

• Failure to maintain a constant distance arc. 

• Failure to maintain altitude during the DME arc. 

• Turning too soon to join the DME arc. 

• Turning too late to join the DME arc. 

• Turning the wrong direction to join the DME arc. 

• Failure to tune and identify the proper navigation facility. 

• Loss of situational awareness. 

• Improper aircraft coordination.

Conclusion

1. Tuning and identification of a navigational facility

2. Setting of a selected course on the navigation 

3. Method 

4. Procedure

5. Recognition of navigation 

6. DME Arcs

(Questions to assess student)

How do we intercept a radial from a VOR

GPS?

How do we know if its right?

What is a DME

How is it flown?

HW: look over IFH