R-Nav 4-Ground direction finder

The maximum theoretical range at which an aircraft at FL80 can obtain bearings from a ground VDF facility sited 325 FT above MSL is:

• 107 NM

• 158 NM

• 134 NM

• 114 NM

What is the maximum range at which a VDF station at 325 ft can provide a service to an aircraft at FL080?

• 134 nm

• 107 nm

• 91 nm

• 114 nm

When conducting a QGH approach responsibility for interpreting the procedure rests with ___ and on a VDF approach responsibility rests with ___

• the controller; the controller

• the pilot; the pilot

• the pilot; the controller

• the controller; the pilot

If, when you are requesting a QDM from an airfield, you are offered a QGH, is means:

• the bearing will only be accurate when the aircraft is flying above the QGH level

• the VDF service will be handled by a different VDF unit, operating on the same frequency

• the VDF unit is prepared to give you assistance during an approach to the airfield, based on VDF bearings

• the service will be limited to bearings, no positions will be given by the DF station

Ground DME responders respond at a frequency:

• the same as the interrogation signal

• 63 MHz grader than interrogation frequency

• 63 MHz lower than interrogation frequency

• 63 MHz different from interrogation frequency, either above or below

The phase difference between the reference and variable signals on QDM 050o (VAR 10oW) for a conventional vor is:

• 050o

• 040o

• 230o

• 220o

A VDF bearing can be obtained:

• only on a frequency of 121.5 MHz

• on the Approach frequency

• on the frequency notified for VDF services

• on the frequency agreed between the pilot and ATC but chosen from one of the available ATC frequencies

Which of the following does NOT affect the accuracy of VDF bearings:

• sky waves

• duct propagation

• ground reflections

• synchronous transmissions

The range at which you can obtain a VDF bearing can be influenced by:

• time of day

• type of surface

• height of aircraft

• intensity of ionisation

At a height of 5.000 feet you might expect to receive a VHF signal, from a transmitter at sea level, at a range of:

• 88,4 nm

• 88,4 km

• 70,7 nm

• 200 km