A few navigational tips for the intrepid

Highmike

Charter Member
I hope I'm not out of order posting a few tips on DR/VOR navigation but I saw Smilo's post about navigating without using the GPS in another thread and I thought it may be helpful to point out a couple of things.

Firstly the FS Flight Planner will give you most of the information you need to navigate by DR and VOR. You enter your departure point and your destination, hit the Find Route button and the crucial navigational details will be listed on the Nav Log which you can access in flight by hitting the F10 key (Shift + F10 in FSX).

Before you exit the Flight Planner hit the destination airport on the panel to the right of the map display of the Edit window. This will zoom the map into your destination where you can drag the red course line over to the VOR station nearest to your destination airport (an NDB will do in the absense of a VOR but this type of beacon will have a limited range compared to a VOR, and no DME). The important point is that the VOR frequency will be listed on your Nav Log which you can access in flight, and which you can use this to tune your NAV radio.

The most important detail listed on the Nav Log is the departure heading and, credit to Microsoft, it is a very reliable indication of where you should be going when you get off the ground.

However, because of wind strength you will have to point slightly into the wind in order to compensate, and a tedious trig calculculation will tell you by how much. Fortunately there is a useful gauge you can add to your panel called a Drift Meter. I reckon the best one is the TWiD Gauge by Glenn Copeland, and you'll find it in the AVSIM library (twidgau.zip).

Inserting the following lines into your panel.cfg will give you a popup panel with this gauge. (You'll need to add to the Window Titles section at the top of the file, but just follow the example of the other panels and then test it in the sim).

//----------------------------------------------------
[WindowXX]
BACKGROUND_COLOR=2,2,2
size_mm=100,100
window_size= 0.15, 0.20
position=8
visible=0
ident=TWiD_Gauge

gauge00=TWiDv1!TWiDv1, 0, 0, 100, 100


//-------------------------------------------------------

When you've got this gauge in the sim you hit the +/- button until the rotating pointer points at your departure heading, and when you get off the ground you adjust your heading using the AP heading bug until the rotating pointer lines up with the wind correction indicator immediately above it. You'll get the hang of it when you get going because it is fairly easy to understand.

This will work well over distances less than 500 miles or so, but with the 1000s miles these jets are capable of you'll have to factor in a great circle course correction which you'll already have a sense of since you've probably seen how your arrival heading sometimes differs vastly from your departure heading. Fortunately it is a simple matter to account for this factor.

Just as you get a departure heading when you enter your details into the flight planner you can calculate the great circle correction factor by entering the reverse course for your trip (say London to New York, rather than New York to London). Entering the reverse course will give you a heading which varies 180 degrees from the heading which you should be arriving at. You get the heading you should be arriving at by adding or subtracting 180 degrees from the heading indicated by the reverse course.

You then get the difference between your departure heading (the foward course) and the result of your reverse course calculation and divide this by the length of your trip. Since there will be no distance measuring equipment until you are in range of the VOR you will have to rely on your clock to tell you when to turn. Say the difference between your departure heading and the result of your calculation is 5 degrees. You divide the length of your trip, say 150 minutes, by the number of degrees. 150 minutes/5 degrees suggests that you should turn left or right 1 degree every 30 minutes to correct for this factor. Just hit the drift meter +/- one degree and then your heading bug until they all line up again.

There are no other factors you will need to factor into your navigational deliberations to arrive at your destination within the range of a VOR or an NDB, say 190 NM for a VOR and between 20 and 70 NM for an NDB.

The real beauty of navigating in this way is the uncertainty involved, and the challenge of finding solutions to this navigational dilemma. Good luck to us all on this endeavour.

Mike
 
many thanks, Mike for the informative post.
now all I've got to do is retain it
and put it into practice, practice, practice.
thanks again.
 
One thing that I do when flying without the GPS is to "chase" navigational beacons to get to my destination. It doesn't work well over water, but rather than just fly DR/wind drift meter most of the way, I'll pick VOR/NDB beacons enroute and just go from beacon to beacon.
 
Mike`s analysis is good for an event like this and Willy`s comment about `chasing`navaids is very relevant.
Two things I`ll add... to Mike`s post:
Firstly the FS Flight Planner will give you most of the information you need to navigate by DR and VOR. You enter your departure point and your destination, hit the Find Route button and the crucial navigational details will be listed on the Nav Log which you can access in flight by hitting the F10 key
When you plan, select VOR to VOR as the option. For most segments it should give you the best route although you can also zoom in to any point along the route and drag your course line over to enroute navaids to fill in gaps.

Planning via navaids will increase the length some but gives you the security of having something to aim at.

Also, the tried and true method - the E6-B computer. Use the section labeled Heading, Ground Speed, And Wind Correction Angle here:http://www.csgnetwork.com/e6bcalc.html
 
Great Info

Who says you can't have fun learnin' stuff?


Basically just wanted to endorse Mike's suggested wind gauge from Glenn Copeland. I used it extensively in the recent MacRobertson Race in a Boeing 247-D and it worked "scary" well.

I'm with smilo in that this whole thread should be in print just for these types of events and for each of us to have as general knowledge.

Superb input from Willy and Rob as well as Mike. Good stuff!

Good luck everybody!
 
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