# VOR Question

Jamie4590 Guest

Is it possible when plotting a course to determine when the VOR will be recieved by the aircraft en route?

In other words can I determine that VOR B will come to life, for example, when I am 10nm from VOR A?

I have been ploting courses using VOR's in FS2002 but unless I actually fly the course I cannot tell when the VOR is recieved or the strength of the signal. I assume for practicality purposes its more preferable to fly a course using the fewest VOR's but how can I tell when faced with a choice of more than one VOR that I select the VOR that comes to life when I am 150nm away rather than only 50nm away.

Thanks!

TDanHogan Guest

VOR's are subject to blockage and "shadowing" caused by obstructions (hills, mountains etc.) and as a "rule of thumb" that I use, for VFR flight I usually anticipate the acquisition of a particular VOR at about 25 nm. For Hi-alt IFR, again, subject to coverage "Gaps", I usually anticipate the acquisition at about 50 - 75 nm.
I try to have at least two VOR's selected to give me a more precise triangulation to a given waypoint. If you go to a local FBO, sometimes, they will have an EXPIRED sectional chart of the area in which you are interested. These will have waypoints (intersections) shown that are the intersection of at least two fairly reliable VOR's.
I hope this helps you in your navigation efforts. Good Flying,

TDH

CRJCapt Chief Captain

VOR Range
Ah, the oft asked and seldom answered question: how far away can I pick up a reliable signal from the Omni and what altitude need I be at? The FAA neatly skirts the answer by classifying Omnis by an altitude code, with the ranges vs. altitudes as shown in the table below.

Reception Range vs. Altitude of VORs VOR Class Range

Terminal (T) 25NM 1000 – 12,000 Feet

Low Altitude (L) 40NM 1000 – 18,000 Feet

High Altitude (H)
40 NM 1000 – 14,500 Feet
100 NM-14,500 – 60,000 Feet
130 NM-18,000–45,000 Feet