Low and Slow

[CaptHill 0]

Hi everyone,

Today I flew my first VFR flight using the Plan G flight planner and it is excellent! The software enabled me to use a very complicated flight plan which meant I would be triangulating my position three times in the space of 30 mins during a little sightseeing trip over Stone Hedge. It also meant I knew when I would be over particular roads etc....very detailed and so satisfying when you see that road pop up on the horizon and your VFR skills worked! (screenshots of flight in screenshot forum)

That brings me onto something else. I did try to plan a triangulation from different VOR's but when I got in the sim, the VORs bought about the barber pole in the OBS display meaning they weren't working. Do all the VORs in Plan G work in FSX? Also I am looking for a nice payware VFR aircraft (possibly from Carenado) that would enable me to triangulate, that is to say contain two Nav radios and two OBS dials. And possibly with DME equipment also. Could anyone make a suggestion?

How does a VFR aircraft with no DME and only one Nav radio triangulate??

Thanks in advance!

Rich

[Tim_A 996]

the VORs bought about the barber pole in the OBS display meaning they weren't working. Do all the VORs in Plan G work in FSX?

Yes. Because the nav data in Plan-G comes *from* FSX.

But you need to be sure that what you have tuned is a VOR. A VOR in Plan-G is drawn as a blue hexagon. If the navaid you have tuned is a blue square it is a DME and not a VOR (so you will see no deflection of the OBS). Many VORs and DMEs are co-located with a common frequency, and so you will see both symbols, ie a hexagon in a square. But there are also many VORs with no DME and many DMEs with no VOR. Standalone DMEs are typically associated with instrument approaches, and will generally be colocated with an NDB or an ILS localiser.

Also make sure it is in range, correctly tuned, and verify the morse ident from the audio panel.

How does a VFR aircraft with no DME and only one Nav radio triangulate??

Use the flipflop button [<->] to toggle the Nav display between two VORs

[CaptHill 0]

the VORs bought about the barber pole in the OBS display meaning they weren't working. Do all the VORs in Plan G work in FSX?

Yes. Because the nav data in Plan-G comes *from* FSX.

But you need to be sure that what you have tuned is a VOR. A VOR in Plan-G is drawn as a blue hexagon. If the navaid you have tuned is a blue square it is a DME and not a VOR (so you will see no deflection of the OBS). Many VORs and DMEs are co-located with a common frequency, and so you will see both symbols, ie a hexagon in a square. But there are also many VORs with no DME and many DMEs with no VOR. Standalone DMEs are typically associated with instrument approaches, and will generally be colocated with an NDB or an ILS localiser.

Also make sure it is in range, correctly tuned, and verify the morse ident from the audio panel.

How does a VFR aircraft with no DME and only one Nav radio triangulate??

Use the flipflop button [<->] to toggle the Nav display between two VORs

Now you see, I would have NEVER thought of that! :001_th_smiles48: Thank you! I take it I would still need to rotate the OBS each time i switched however?

Thank you for pointing this out, I was attempting to tune a DME with no VOR.

Rich

[allardjd 1,853]

That brings me onto something else. I did try to plan a triangulation from different VOR's but when I got in the sim, the VORs bought about the barber pole in the OBS display meaning they weren't working. Do all the VORs in Plan G work in FSX? Also I am looking for a nice payware VFR aircraft (possibly from Carenado) that would enable me to triangulate, that is to say contain two Nav radios and two OBS dials. And possibly with DME equipment also. Could anyone make a suggestion?

How does a VFR aircraft with no DME and only one Nav radio triangulate??

VORs have limited range. I think there are three versions in FS9 - not sure about FSX. The "High" VORs have a range of, I think, 105 NM; the Low VORs are limited to 60 NM and the Terminal VOR's to 38 NM. ILS with the DME feature is even less, maybe something like 19 NM. I suspect that FSX is similar, but not sure.

Navigating by VOR is typically done by flying along a radial, directly to or from a VOR station, though RNAV will permit you to follow a course that does not lie along a radial. VOR to VOR navigation becomes a bit of a zig-zag flight path, but in tracking long range flights by that method I find that it seldom adds more than about 5% to the total distance, but does add a lot of interest.

While tracking along one radial, the second NAV radio/OBI can be used to take cross bearings from other nearby stations which will help establish where you are on the radial you're tracking in the absence of DME. GPS has made that all but obsolete today except for the hardcore Luddites like me who choose to not use it. Real point to point navigation is best done using that.

Triangulation is possible, even with a single VOR but I think it's done more to find where you are in a general sense than to navigate precisely. You can tune a VOR, adjust the OBI to get your bearing from (or to) the station, then quickly tune another and do the same thing, establishing your position on a sectional chart with enough precision to allow you to navigate. Even using the frequency switch button you'll have to manually re-center the needle on each station and that gets kind of tedious. It works, but without applying pilotage techniques, it's not going to let you find a specific road intersection.

Be careful of DME if you are high and close to a station - DME is slant distance to the station, so if you are low or far away it's reasonably precise. As the angle to the station diverges from the horizontal, a distance error creeps in. If you overfly a sea-level station at 15,000 feet, your DME will never register less than about three miles.

John

EDIT: Re ILS, I think I got that wrong. The localizer comes alive at about 27 NM but the glide slope doesn't get active until about 19 miles.

JDA

[Tim_A 996]

VORs have limited range. I think there are three versions in FS9 - not sure about FSX. The "High" VORs have a range of, I think, 105 NM; the Low VORs are limited to 60 NM and the Terminal VOR's to 38 NM. ILS with the DME feature is even less, maybe something like 19 NM. I suspect that FSX is similar, but not sure.

Plan-G will tell you the range of VORs & NDBs - just hover the mouse over it and it's displayed in the tooltip.

Rich: Yes you will need to rotate the OBS dial each time. Crossed bearings is a standard triangulation technique, but you'd typically only do it during every other FREDA check, unless you particularly needed a more frequent fix.