Radio Navigation Aids

Question 1

What is Automatic Direction Finder (ADF)?

Answer 1

• ADF is used to measure the bearing from 2 or more ground beacons to determine one’s position.
• ADF provides only bearing information.
• The bearing of an aircraft requires 2 or more non-directional beacons.
• ADF determines the bearing of a ground beacon with regards to an aircraft bearing.

Question 2

What is Direct Moving Equipment (DME)?

Answer 2

• DME measures direct distance.

Question 3

What is Distance Measuring Equipment (DME)?

Answer 3

• DME measures distance by transmitting a signal and waiting for a reply from the ground station.

Question 4

What is Tactical Air Navigation (TACAN)?

Answer 4

• TACAN provides aircraft with bearing, distance and navigational aid.

Question 5

What is VHF Omnidirectional Range?

Answer 5

Most significant is that VOR provides a bearing from the station to the aircraft which does not vary with wind or orientation of the aircraft. VHF radio is less vulnerable to diffraction (course bending) around terrain features and coastlines.