29
votes
Why is there a grid below the antennas of an VOR?
I think this is an example of a counterpoise:
[It] is a network of suspended horizontal wires or cables (or a metal screen), used as a substitute for an earth (ground) connection in a radio antenna ...
- 1,467
27
votes
Accepted
Why is there a grid below the antennas of an VOR?
I would imagine the main reason is to make the performance of the antenna system more predictable and consistent.
Many antennas systems need a ground reference. All antenna systems are affected by ...
- 1,621
22
votes
Accepted
Why am I not getting the "TO" VOR flag as I think I should?
A quick review of the US Chart Supplement shows that the Lovelock VOR (LLC) is unusable at your current altitude and position. The VOR is 3.6 NM North by Northwest from the field. Your aircraft is 24....
- 16.5k
19
votes
Accepted
What is the difference between conventional VOR and Doppler VOR?
Short answer:
There are several types of conventional VORs using either rotating or static antennas. What they have in common is:
They are relatively compact.
Bearing is determined from a HF signal ...
- 69.9k
19
votes
Accepted
What radial is the aircraft crossing?
A radial is always pointing (radiating) away from the VOR. But your instrument shows the TO/FROM indicator as TO. So you are crossing a 210 course towards the VOR, which means you are on the 030 ...
- 53.7k
18
votes
Accepted
What causes the phase to change in a VOR?
The latest decades VOR are Doppler VOR (DVOR) where the bearing signal is produced by a 14 m diameter circular array of fixed Alford loops antennas. An additional central antenna radiates the ...
- 69.9k
17
votes
Accepted
Do some modern VORs not spin?
There are no spinning parts in the VOR.
It typically uses 60 antennae in a phased antenna array to steer the beam in a rotating sweep.
The VOR transmits a constant omnidirectional signal. The phase ...
- 31.1k
17
votes
Accepted
Is VOR identification automated in modern avionics?
Modern air transport and bizjet avionics do decode the audio ID and provide it digitally on the data output bus. This data is displayed on the Nav display or RMI (depending on Mode) along with the ...
- 19.2k
15
votes
How many channels does the VOR have?
As shown by this Source:
VOR are exploited over the Very High Frequency (VHF) band from 108 to 117.95 MHz with channels spaced of 50 or 100 kHz (50 kHz for dense zones, 100 kHz elsewhere). The first ...
- 32.5k
14
votes
Can a pilot use their GPS/FMS to fly a VOR or NDB approach?
In the US they can (Effective: May 26, 2016).
This change allows for the use of a suitable RNAV system as a means to navigate on the final approach segment of an instrument approach procedure (IAP) ...
- 7,371
14
votes
Accepted
Are NDBs and VORs dying as a navigational method?
Yes, without a shadow of a doubt. Many airports now publish GNSS (Generic term for all types of satellite navigation) approaches, completly negating the need for those aids even during complex, ...
- 9,190
14
votes
Accepted
What does the letter "H" on the upper side of ADANA word and mean?
Customers have stated "We noticed an 'H' symbol next to an airspace
fix/navaid in the SID/STAR chart planview. Explain what this means?"
The "H" symbol serves as an indicator for ...
- 668
13
votes
Accepted
Why would a VOR be decommissioned leaving the DME?
Many older Air Transport Airplanes have no GPS. I'm a pilot since 1970. I operated A330 for 5 years until 2000 without GPS. The average IRS position (Inertial Reference Systems) in the FMS was updated ...
13
votes
Accepted
How wide is the cone of confusion above a VOR and NDB?
The value +/-40° is correct, but need to be interpreted. The primary reason of the existence of a "silence" (confusion) cone is a design choice to increase navaid range. Range and "...
- 69.9k
12
votes
How wide is the cone of confusion above a VOR and NDB?
Isn't it too much?
No, it isn't. VOR's and NDB's are pretty old technology. VOR's were introduced in the 1930's and 40's, but are still commonly used today.
If you have a cone of confusion of 45 ...
- 35.7k
12
votes
Why do we have to manually tune VOR receivers?
As pointed out in the comments, I think you have things turned around. If you select the frequency of a VOR that has a co-located DME, the system will automatically also select the DME frequency. Thus,...
- 39.1k
12
votes
Accepted
How can a pilot fly a distance of 594 NM connecting two VOR's?
You are correct that VOR's rarely have a range of more than 200 NM. However, Alta Floresta VOR (ATF) is colocated with an NDB (and DME). In spite of less accuracy, NDB's have a much greater range (...
- 35.7k
12
votes
Accepted
Why wouldn't KJFK offer the ILS for 22L?
JFK ARR ILS 22L/22R DEP 22R
If conditions dictate the use of JFK ILS RWY 22L approach, then (1) the JFK Area owns Belmont airspace 3,000' and below, (2) releases Coney airspace to LGA and LIB, (3) ...
12
votes
Are NDBs and VORs dying as a navigational method?
Yes, it is true. This FAA page has more info.
The Very High Frequency Omni-directional Range (VOR) Minimum
Operational Network (MON) provides a conventional navigation backup
service in the event of ...
- 7,371
12
votes
Accepted
What is Automatic Radial Centering on a VOR indicator?
As the name indicates, this automatically centers the CDI needle, by selecting the appropriate TO radial. From the manufacturer of INS 422, an integrated navigation system including a VOR:
Pushing ...
- 69.9k
12
votes
What would be the likely indication on the VOR for the below question?
The aircraft is on a radial. Just not the one marked on the diagram.
Notice that figures 1, 3, and 4 all have heading 210° dialed at the top of the instrument. However, figure 2 has heading 120° ...
- 12.8k
11
votes
Accepted
Are there two navaids on the same frequency close enough to be confused?
Short answer
ICAO recommendations include a protection for same-frequency navaids, restricting the received power of undesired stations to a level preventing interferences. To meet this restriction ...
- 69.9k
11
votes
Why is the treatment of magnetic variation different for NDB and VOR?
The reason is, that for a VOR, the receiver in the aircraft determines the radial based on calculating the phase shift and as the VOR is oriented to the magnetic north of its location, we need the ...
- 271
10
votes
Accepted
Are nearest VOR stations always tuned to?
Your example is a bit confusing because it seems to be a GPS-based route, it may be better to a look at a more 'realistic' one, where you're using only VORs for navigation. The reason to tune a second ...
- 71.5k
9
votes
Accepted
VORTAC symbol over KMOT airport - is the small dot the center?
The dot in the center of the star means that there is a rotating beacon available on the airport from sunset to sunrise.
See the FAA Aeronautical Chart Users Guide Page 8.
The actual center of the ...
- 36k
9
votes
Accepted
Can a pilot use their GPS/FMS to fly a VOR or NDB approach?
No, you still have to monitor the underlying NAVAID. You just have to read further in that same section of the AIM. Reference the most recent edition of the AIM, which has Change 3 dated April 27, ...
- 106
9
votes
Accepted
What do the white circle and black arrow on the airport chart mean? (VOR identifier and frequency written)
I believe that the circle and black arrow (with the VOR identifier and frequency) noted on the airport diagram in your question represents
a "VOR Aerodrome Checkpoint Marking" (Source: ICAO-...
- 32.5k
8
votes
Accepted
Where does the Garmin G1000 Nav ID come from?
Garmin doesn't explicitly state the method in the documentation I can find, but I believe the answer is #1. It decodes the Morse code and displays that value. I say that for two reasons:
First; ...
- 19.2k
8
votes
Accepted
What would be the likely indication on the VOR for the below question?
Perhaps a graphic can help you. See the picure.
The ac is flying with TO indication (radial 120 selected) in a FROM area. This shows that number 2 is the correct answer.
- 1,353
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