Radio Navigation Flashcards
What does VDF stand for
VHF DIRECTION FINDING
A PILOT or CONTROLLER would use a VDF aid
CONTROLLER
How does a VDF work
- Pilot transmits
- VDF calculates direction of transmission
NOTE: DOES NOT include range
Allows a pilot to plot his position from different ATSU services equipt with VDF
Bearing classifications and accuracy levels
What are the accuracy levels of the following classes;
Class A
Class B
Class C
Class D
- A = ± 2॰
- B = ± 5॰
- C = ± 10॰
- D = > 10॰
Bearing classifications
What are the 4 classifications
A, B, C & D
VDF Bearings to the aircraft
What is the definition of;
QDM
MAGNETIC heaing TO station
REMEMBER: qDM
Direction Indicator
Remember the “mmmm” sound in hoMe “hoMMMe”
Use DI to navigate hoMe TO the airfield
VDF Bearings to the aircraft
What is the definition of;
QDR
MAGNETIC heading FROM station
REMEMBER: qDR = Radial
Direction fRom the Radial
The STATION is at the center
VDF Bearings to the aircraft
What is the definition of;
QUJ
TRUE bearing TO station
“QU” sounds like TO
VDF Bearings to aircraft
What is the definition of;
QTE
TRUE bearing FROM station
REMEMBER: qTE
True fix from Equipment
VDF Bearings to aircraft
What is the definition of;
QGH
CONTROLLER INTERPRETED
Controller advises aircraft of hearings & heights based on transmission
REMEMBER QGH
Ground Help
To obtain a position fix, a pilot will request TRUE or MAGNETIC bearings
TRUE
What does ADF stand for
AUTOMATIC DIRECTION FINDING
How does a pilot use an ADF
Tune to a specific NDB
Pointer points towards beacon
What frequency bands does an NDB transmit on
Nominal Deutsnches Bahn
LOW to MEDIUM
Nominal Deutsnches Bahn
DB have low to medium customer service
What are the 2 transmission types of an ADF
Remember: Long and Short in sequential order
- N0N A1A (Long range)
- N0N A2A (Short range)
What does a N0N A1A transmission require
BEAT FREQUENCY OSCILLATOR
(BFO)
Required for IDENT
DJ A1A down with the beat
For a short range N0N A2A, how does the ADF ident
IDENT available on ADF settings
Bearings are usually interpreted as TRUE or MAGNETIC
MAGNETIC
On an aviation chart, what are the 2 pieces of information provided to identify an NDB
- BEACON IDENTITY
- FREQUENCY
When setting up an ADF on the instrument, what does SID mean
Select
Identify
Display
What is a relative bearing
Bearing to the NDB relative to the aircraft nose
If DI is showing aircraft travelling west (270॰) and the NDB is 45॰ off of its rear starboard side, the relative bearing is 200॰ i.e. starting from the nose, its 220॰ to the bearing.
The actual true bearing would be 120॰ from north
what is an NDB bearing
Bearing TO or FROM NDB relative to North
If aircraft is on a bearing FROM the NDB, the pointer will pointing backwards
If the aircraft is on a bearing TO the NDB, the pointer will be pointing forward
EXAMPLES;
1. Aircraft is flying on the DI bearing of of 050॰, the ADF needle is pointing exactly backwards.
If the arrow were super imposed over the DI, the NDB would be directly behind us, meaning we are on a 050॰ bearing FROM the NDB
2. Aircraft is flying on the DI bearing of 330॰, the ADF needl is pointing exactly forwards
If the arrow were super imposed over the DI, the NDB would be directly infront of us, meaning we are on a 330॰ bearing TO the NDB
ADF station passage
What is the degree of the “cone of silence” from the NDB, and what happens to the aircrafts needle as it flies through the cone
- 40॰
- Wanders aimlessly
What are the 4 things affecting the accuracy of an ADF
N C Q D
- Night Effect
- Coastal Refraction
- Quadrantal error
- Dip error
When used during the day, ADF bearing accuracy should be what value in degrees
-/+ 6॰
What does VOR stand for
VHF Omnidirectional Range
How does a pilot leverage a VOR
Tune aircraft equipment into ground beacon
2 x 30Hz signals ; reference & variable
Signal presented to pilot, enables them to determine bearing FROM the beacon
The imaginary line painted on a specific magnetic bearing relative to a VOR is known as what
RADIAL
Imagine a straight line draw through the VOR, the line will intercept the radial i.e. if a 185॰ is given, imagine a Radial drawn over the VOR, now imagine a straight line from the VOR in the middle of the radial out to the 185॰ mark. This is the radial line.
Radials are always referred to as being TO or FROM the VOR
FROM
4How many COMs and NAV frequencies are required for a VOR
2x NAV
2x COM
4
Each mark on the VOR receiver window is equal to ____॰ of VOR Radial
2॰
If the aircraft is flying a heading of 300॰ and on the VOR instrument, the white line was in perfect center and the TO/FROM arrow was saying TO, what bearing would be indicated at the top.
300॰
You are on a bearing of 300॰ TO the VOR
If the aircraft is flying a heading of 300॰ and on the VOR instrument, the white line was in perfect center and the TO/FROM arrow was saying FROM, what bearing would be indicated at the top.
120॰
You are on a bearing of 120॰ FROM the VOR.
In other words, if you looked at an aviation chart, you would turn 120॰ around the radial until you aligned with the track that matches to where the aircraft is coming from.
If the VOR window indicates the TO VOR flag the aircraft IS or IS NOT on the same side as the VOR
IS NOT
The side of the VOR is identified as +/- 90॰ from the selected radial from the VOR.
The Radial is set to 330॰. The aircraft might be flying a heading 010 which is within 90॰ of 330॰, but the aircraft’s actual position relative to the VOR radial is 070॰.
This makes the aircraft TO the set radial but on the path it’s flying once it crosses the 90॰ line drawn over the VOR relative to the radial set (060॰), the flag will change to FROM as it would now be on the same side.
If the VOR window indicates the FROM VOR flag, the aircraft IS or IS NOT on the same side as the VOR
IS
The side of the VOR is identified as +/- 90॰ from the selected radial from the VOR.
The Radial is set to 330॰. The aircraft might be flying a heading 070 which is not within 90॰ of 330॰, but the aircraft’s actual position relative to the VOR radial is 010॰.
This makes the aircraft FROM the set radial but on the path it’s flying once it crosses the 90॰ line drawn over the VOR relative to the radial set (060॰), the flag will change to TO as it would not now be on the same side i.e. within 90॰.
What does CDI stand for
COURSE DEVIATION INDICATOR
As good practice, what should a pilot always ensure appears in the top of the OBS
CDI Heading
What does OBS stand for
OMNI BEARING SELECTOR
VOR station passage
What is the degree of the “cone of confusion” from the VOR, and what happens to the aircrafts CDI as it flies through the cone
- 50॰
- TO/FROM indicator may flip erractically
- NAV fla may be present
What is the altitude of the VOR “cone of confusion” and what is the radial diameter (in nm) of the cone at this altitude
- 30,000ft
- 11.8nm
What is the VOR total system transmitter and receiver error in degrees
< 5॰
What does DME stand for
DISTANCE MEASURING EQUIPMENT
What is a pilot able to do with the use of one co-located VOR-DME
PLOT POSITION
What are the 3 display outputs from a DME in the aircraft
- Time to station
- Groundspeed
- Distance from station
At co-located VOR/DME stations, if you tune in to ident, what pitches will the code be given in for;
1. NDB
2. VOR
3. DME
- Low
- Medium
- High
Speed and time in relation to a DME ground station is only valid in what 2 circumstances
- FLYING TOWARDS
- FLYING AWAY
If flying around a DME, speed will turn to 0 kts and time will increase to 999 min
DME is measured in slant range. What is the significance of this
The distance between the aircraft and the DME station is actually slightly more than if the aircraft were at ground level from the same location.
Rule of thumb; for every 1nm you are away from a DME, for every thousand feet, the error is negligible.
i.e. If you are 1nm away and 1000ft, or 5nm away and at 5000ft, error is negligible
A VOR indicates the direction an aircraft should fly to get to the beacon, TRUE or FALSE
FALSE
A VOR only shows the aircrafts relative position to a given VOR Radial
What instrument does each of the following detail
1. Includes a to and from flag. It does not indicate which direction the aircraft should fly
2. Includes a pointer which indicates the direction the aircraft should fly
3. includes a digital interface that presents the distance in nm, time in minutes, and speed in knots
- VOR
- ADF
- DME