• Ratty's Ramblings - Getting Around

    Ratty's Ramblings

    Ratty's Ramblings - Getting Around

    By Ian Radcliffe

    I'm a simple soul. I mostly fly general aviation aircraft and warbirds: a propeller and a wing and I'm good to go. And I love simple navigation: back when I learned to fly, although our field had a VOR, almost none of the planes there had a receiver, so I got around with just a map and a "Dalton Computer", the British E6B.

    I was mad about airplanes even as a little boy, and I had learned a lot about VFR navigation long before I ever got to do it for real. It's hard for me to appreciate the kind of challenge that navigation presents to a newcomer who wants to explore but has little idea what it takes to get around. In that situation, to just get up in the air and go places, the GPS is an incredible aid. Once you've figured out taking off and landing, and straight and level flight and autopilot operation, you're free to fly anywhere in the world.

    I guess the problem I have with that is that it skips the traditional steps that instill basic airmanship skills. As I've noted before, our simulated aircraft are too reliable, so you'll probably never suffer a total electrical failure, but if you were to lose your navaids, would you still be able to get where you're going or, for that matter, even figure out where you are?

    Navigation is a complex subject and because we fly in a dynamic medium it's almost as much art as science. But at its heart, aerial navigation is simple. As long as you can see the ground, a map and compass and a clock will do just fine: point the plane in the direction you want to go, keep track of your position on your map, and correct for drift. Let's try a little trip with just those tools, some minimal preflight planning - and no GPS.

    Go to ESMK, Kristianstad, Sweden. Set time to Day and season to Spring. Choose your weather; anything will do, as long as the clouds are higher than 1,500 feet, but if this is your first time, I recommend a selection with light winds and decent visibility. Pick a plane from your collection; the trip is only 63 miles, so something simple, with a cruise speed in the 90 - 120 knot range.

    Open Skyvector.com. Go to Kristianstad, ESMK and mark your start point. Go to Halmstad, ESMT, and mark your destination. Now right click on the line at the first lake to the north west of ESMK and set a "GPS" marker. It should be eighteen miles away on a bearing of 313 degrees. Fifteen miles further on there is a road perpendicular to your flight path, just past a fairly distinctive lake. Set another marker where the flight path crosses the road. The finished product should look like this:

    Ratty's Ramblings - Getting Around
    Full map at skyvector.com

    Do what you need to do to prepare for flight. Start up, taxi out, and take off. Circle the field, climbing to 1,500 feet. Turn onto a heading of 313 degrees and overfly the field. Note the time or start a stopwatch.

    At 90 knots, a mile and a half a minute, the lake is about 12 minutes away; at 120 knots you're going two miles a minute, so the lake is about nine minutes away. Maintain your heading of 313 degrees. You'll see the lake pretty soon. Keep going.

    When you get to the lake, or abeam the lake, pause the sim and note the time. Multiply 18 (the distance flown) by 60, and divide by the time in minutes. The result is your groundspeed for this leg. If it's more than your airspeed you have a tailwind, if less, a headwind. Armed with this information you can calculate how long the next fifteen miles should take to fly and estimate your time of arrival at the next waypoint.

    Take a look at where you are in relation to your intended flight path. If you held a steady heading of 313 degrees and finish up off to one side it's probably because the wind blew you off course (though there may be a small difference between Skyvector's magnetic north and yours). To adjust for drift, find out how many degrees off course you are. You can do this in Skyvector by pulling your course line to your actual position, thus:

    Ratty's Ramblings - Getting Around

    The E6B/Dalton Computer is a wonderful tool. With it and the information you now have - your heading, track, airspeed and groundspeed - you can calculate the direction and speed of the wind. You can then use those numbers to calculate how much to point your plane into the wind to allow for drift. Or, since this is a little 30-minute jaunt, you can just steer a bit to the right.

    From this position you have a number of options. If you turn five degrees to the right you will correct the drift, but you'll now be running parallel to your original intended track. To get back on track, you need to turn ten degrees to the right, fly that heading for the same amount of time, then turn five degrees back to the left. Alternatively, using the map, you can plot a new heading to the next waypoint and "allow for drift". Or you can plot a new heading to the destination, allowing for drift. Pick your method, make your best guess at the wind correction, unpause, make your heading change, and press on.

    Try to match your progress on this leg with features on the ground. There are roads, a railroad, and lakes to look out for. But be careful with lakes; in MSFS the programmers did a fantastic job replicating the lakes around the planet, but a few have changed shape or disappeared over time, and there can be differences between what Skyvector shows and what you see in your sim.

    The highway you're looking for as your next waypoint is a "line feature". Line features like roads, rivers, railroads, and coastlines are very useful. Following one can get you where you want to go. (Please remember, keep to the right.) Crossing one, it's usually easy to fix your position on it. Best of all, if you ever get lost, flying to intercept a line feature can get you found again.

    Whichever wind correction method you used, when you get to the highway note your time and position again. You can use this to check how well your corrections are working out, make adjustments for the last leg, and calculate the time you'll arrive at Halmstad.

    Once again, follow your progress on the map. There's a big lake about half way along, and very distinctive inlets and rivers as you near the coast. That confluence of river and railroad lines directly on your track is ten miles out from the field, a good point at which to call them up and get your landing instructions. Land and park and grab a burger. Then fly back.


    3 Comments
    1. sfgarland's Avatar
      sfgarland -
      another Great ! and informative article . . . . . thanks again
    1. Kukailimoku's Avatar
      Kukailimoku -
      great. thanks.
    1. Jezz006's Avatar
      Jezz006 -
      Thanks for the informative article and great flight :-]
  • Recent Forum Activity

    Bus Driver

    Another Newcomer

    Thread Starter: Bus Driver

    Hello: Also a newcomer. Not real good with computers; presently an FO on the EMB 145. Haven’t flown since getting type ride in March due to...

    Last Post By: Bus Driver Today, 02:40 AM Go to last post
    robasket3535

    FS2004 Won't Open in Windows 10

    Thread Starter: robasket3535

    Hi all, I've recently upgraded my SONY VAIO VPCL218FW to from WIN7 to WIN10. Like everyone else, I have trouble opening FS2004. I've read many...

    Last Post By: robasket3535 Today, 01:28 AM Go to last post
    jparnold

    Where to purchase?

    Thread Starter: jparnold

    When I go to the Microsoft web site to preorder FS2020 sometimes it displays a window stating that it has detected I am in Australia and gives me the...

    Last Post By: jparnold Yesterday, 11:49 PM Go to last post
    Downwind66

    Came to visit with you guys at the IA27 Fly-In. Nobody's here?

    Thread Starter: Downwind66

    Maybe David scared everybody off with his aerobatic demonstrations??? Oh well, guess I'll go home! Needed some time in this classic of...

    Last Post By: Downwind66 Yesterday, 10:58 PM Go to last post