Newbie VOR question

"Bruce W.1" wrote:
But doesn't everbody flying
TO/FROM VOR stations cause air traffic problems like near misses
(collisions)? Or being aware of this do you just watch the skies very
carefully near VOR stations? Or are there altitude guidelines for each
radial?

Sort of. There are rules defining what the usable altitudes are based on
magnetic course being flown. Opposite direction traffic should be at least
500' apart, vertically. This offers no protection, though, for aircraft
flying in the same direction or on converging courses that are on the same
side of the compass.

http://www.faa.gov/ATPUBS/AIM/Chap3/aim0301.html#3-1-5 defines VFR cruising
altitudes, which are 1,000' apart. IFR altitudes are 1,000' apart, too, but
are 500' above or below VFR altitudes. Above FL290 the IFR cruising
altitudes are 2,000' apart.
--
Dan
C-172RG at BFM

On Mon, 04 Apr 2005 18:58:38 GMT, "Bruce W.1" wrote:


You're probably right about the distance. But doesn't everbody flying
TO/FROM VOR stations cause air traffic problems like near misses
(collisions)? Or being aware of this do you just watch the skies very
carefully near VOR stations? Or are there altitude guidelines for each
radial?

Traffic may be heavier over VORs, and the closer your heading is to
due North or South (where the hemisphere[1] rule toggles, the more
alert you should be.

That said, I've never actually noticed a particularly heavy increase
in traffic over VORs.

Don
[1] Why hemiSPHERE? Semi-circle I could see, but . . . .

On Mon, 04 Apr 2005 18:58:38 GMT, "Bruce W.1" wrote in
: :

Larry Dighera wrote:

You'd be surprised at how little the distance increases on a VOR route
compared to a direct route.


=============================================== =

You're probably right about the distance. But doesn't everbody flying
TO/FROM VOR stations cause air traffic problems like near misses
(collisions)?

Congested airways near VORs can be an issue. But the designers of the
VOR airway system had enough insight to separate east and west bound
VFR traffic by 1,000' vertically, and IFR traffic from VFR traffic by
500'. But airways, being only 4 nautical miles wide either side of
centerline can be congested over VORs.

Or being aware of this do you just watch the skies very
carefully near VOR stations?

Yes. That and ATC Radar Advisory Service are the principal methods
used to separate VFR flights on VFR airways.

Or are there altitude guidelines for each radial?

Nope.

Have you spent any time reviewing this:
http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgFAR.nsf/CurrentFARPart!OpenView

"Bruce W.1" wrote in message

I'm not a pilot but I have been reading up on VOR stations. And I'm
looking for practical information.

You can calculate your position by triangulating from two VOR stations.

Well, just calculating an intersection. Thhere's always a question or two
about this on PPL and CPL exams.

How many pilots do this? Or do most just fly between omnis? When you
fly cross country do you just fly VOR to VOR, or do you draw a straight
line to your destination and constantly triangulate while enroute to see
if you are on this line?

Very few. A 20.00 GPS is more accurate. Get two, JIC.

Is it practical to fly a straight line course? Anybody do this?

VFR? Sure. IFR? With GPS, more and more.

moo

If you purchase an aviation map (Sectional Chart) it will show airways
based on flying from VOR to VOR, and many pilots still use these for
navigation even when GPS is on board. In my Instrument Proficiency
Checkride last week, the instructor asked me after practicing a bunch
of maneuvers to use triangulation to figure out without looking out the
window where we were. When I showed him the general area we were
located, he asked me to fly to one of the VORs using the 260 degree
radial. This required flying north until the needle centered, then
turning to 260 degrees.

Bruce W.1 wrote:

You can calculate your position by triangulating from two VOR stations.
How many pilots do this? Or do most just fly between omnis? When you
fly cross country do you just fly VOR to VOR, or do you draw a straight
line to your destination and constantly triangulate while enroute to see
if you are on this line?

When I navigate using the VOR network, I usually go VOR to VOR in congested
airspace and straight line for long cross-countries. When traveling straight
line, I frequently use the triangulation method to verify my location when there
are no good landmarks nearby. I frequently use triangulation to determine the
point at which I pass an intersection or waypoint (whether official or
otherwise). For example, I may fly one radial from VOR "A" to remain outside the
DC ADIZ, but I know that I can change course once I pass the point at which a
particular radial of a second VOR crosses that one. In any case, I treat the VOR
network as sort of a backup to pilotage (and I treat pilotage as a backup to
LORAN/GPS).

As Larry pointed out, in most cases, using the airways usually doesn't increase
your enroute time all that much over going direct.

George Patterson
Whosoever bloweth not his own horn, the same shall remain unblown.