Results
Q1. In VDF service the report “QDR 235, Class C” means
The magnetic bearing from the station to the aircraft is 235 +/- 10°
Q2. The maximum theoretical range at which an aircraft at FL80 can obtain bearings from a ground VDF facility sited 325 FT above MSL is:
134 NM
Q3. In which one of the following circumstances is ground direction finding (VDF) likely to be used to fix an aircraft’s position?
When using the emergency VHF frequency 121.5 MHz
Q4. Which of the following is an advantage of Ground/DF (VDF) let-down?
It only requires a VHF radio to be fitted to the aircraft
Q5. Abnormal long ranges may be experienced on VDF channels, caused by
Super refraction of signals in the atmosphere
Q6. If, when you are requesting a QDM from an airfield, you are offered a QGH, it means
The VDF unit is prepared to give you assistance during an approach to the airfield, based on VDF bearings
Q7. What is the approximate maximum theoretical range at which an aircraft at FL130 could receive information from a VDF facility which is sited 1024 FT above MSL?
180 NM
Q8. What is the minimum level that an aircraft, at a range of 113 NM, must fly in order to contact the tower on R/T for a VDF bearing from an airport sited 169 FT above MSL?
FL60
Q9. In the VDF system directional antennas are used
At the ground installation
Q10. What airborne equipment, if any, is required to be fitted in order that a VDF let-down may be flown?
VHF radio
Q11. The indicator of the ground VDF equipment responds to
The carrier wave received
Q12. VDF for aeronautical use provides service in the frequency band
118-137 MHz
