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Will273

Navigation

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I'm re-learning everything since being out of the loop for awhile and have forgotten a lot. As for navigation and the autopilot...I think I understand the nav/gps switch...with autopilot engaged and switch on nav mode the autopilot will follow whatever VOR is tuned in and when switched to gps it follows the flightplan. So what happens if the flightplan is all VORs...if switched to nav mode will the autopilot follow the flightplan completely or would I need to have it in gps mode? Another thing is how is navigation done these days since they're going to phase out VORs? I've heard about gps waypoints and I guess using fixes too. This brings up another thing...I can't really rely on fixes that much because they're out of date so I use mainly VORs...or at least I used to before I took a leave of absence from simming. I've heard about updating the navdata from some websights but never tried it so I just stick with VORs to keep it simple. Can anyone give me some info on any of this please? Thanks!

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Hi Will,

Yeah - GPS navigation is really the thing today - many NDB's and some VOR's have been decommissioned - there are still plenty of VOR's out there though... Many GA aircraft still don't have a GPS although most pilots now have an iPad with some type of EFB in the cockpit... The iPad is not approved for official navigation (only for situational awareness) but I would bet many use it that way...

Yeah - in GPS mode most autopilots will follow the magenta line automatically - all the addon GPS's (F1/RXP) are WAAS (higher fidelity) models so they are fully approved for GPS RNAV approaches - this is where the GPS provides a virtual glide path where no ILS equipment exists or is used...

Being a fan of redundancy - when I fly with GPS - I'm still tuning VOR's along my route of flight on cross country flights out of my local area...

If you are in LOC mode - and using VOR's for navigation - you need to tune each subsequent VOR along your route of flight - the AP will not just follow on its own...

By 2020 - all aircraft need a new system added to them called ADS-B - this is where the aircraft knows it's GPS position and broadcasts it to ATC - which will allow ATC to phase out Radar... 

Regards,

Scott

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Ok well...if I used VORs for the flightplan and used the gps mode instead of nav mode would the autopilot follow the flightplan? Thanks Scott

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While GPS is, in reality, the navigation method now going forward, old-school VOR navigation is still good to know and practice. I personally find it much more interesting in simulation to have to actively engage in the navigation process. ...of course when the weather is VMC I still whip out my old E6B and plan using dead reckoning with no radio navigation at all.

But to answer your question, if you enter VORs as your waypoints in the GPS and switch it to GPS mode, it should automatically fly the route for you.

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Thanks very much snglecoil...that's what I wanted to know.

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Another nice thing about GPS navigation is the ability to add user-created waypoints.

I do a lot of bush plane flying into small airstrips in the sim. I always start with a flight plan created in the free/donationware Plan-G Flight Planner. After entering the departure and destination airports, I'll use the "add user waypoint" feature for things like the start of a descent profile, then another one for a final approach fix and turn towards the runway. Then I export the flight plan to my sim, load it into the GPS, and I'm good to go.

I could do the same thing by manually inputting custom waypoints in the aircraft GPS with Lat/Long coordinates, but it's so much easier with a good flight planning software.

And of course you still have to stay on top of the autopilot when running those waypoints, making sure you know where you are, and what it's doing. It's not a bad idea to have a good grasp of VOR and NDB navigation for a cross-check. There are many places in the world where VORs may be starting to phase out, but there are still many NDBs around for navigation.

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6 hours ago, scottb613 said:

Being a fan of redundancy - when I fly with GPS - I'm still tuning VOR's along my route of flight on cross country flights out of my local area...

If you are in LOC mode - and using VOR's for navigation - you need to tune each subsequent VOR along your route of flight - the AP will not just follow on its own...

I might add to the great descriptions Scott has provided.  When in VLOC mode, the autopilot (or pilot if flying without AP) is following the radial tuned on the OBI (Omni Bearing Indicator) instrument, which itself is tuned to a radio frequency beacon on a NAV radio.  The signals from the beacons extend only so far, and vary by beacon and surrounding terrain. 

Most NAV radios allow tuning of two frequencies, an active frequency, and a stand-by frequency. Pilots flying in NAV mode manage the transitions from one beacon to the next by tuning the next flight plan beacon to the standby frequency.  The pilot at that point also has to dial in the appropriate navigation radial for that next waypoint or VOR on the Omni.   The transitions usually come at approximately the halfway points between the beacons, but not always.

The transition points and to/from distances used to be marked on IFR charts, and pilots then would judge when to switch over the standby frequencies based on the distance shown on the DME (distance measuring equipment) gauge.  If you are flying in VLOC you must manage the transitions manually, even if flying on autopilot.  In other words, in VLOC mode the autopilot is not following a flight plan, it is merely following what you do as a pilot with the NAV radio and Omni.

The autopilot and GPS, in GPS mode, work differently together  Radio frequencies and navigation radials are not even used. Only flight plan navigation waypoints based on latitude/longitude.  The waypoints may be, and mostly are the same as corresponding beacon locations, but are defined by Lat/Lon not as radio frequencies.  The GPS steers the AP from point to point on a direct basis, so though the GPS may show the bearing to the next point in degrees, it is simply steering directly to that next fix.  So the GPS is able to drive the AP without need for the pilot to manage radio frequencies or transition points and radials.

Edited by fppilot
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I like flying TO and FROM VOR's by hand in single engine props while maintaining altitude, ADF is even more fun with cross winds blowing you off course, autopilot and GPS is boring, nothing like the satisfaction of arriving at your destination on your own unassisted by electronics, keeps your brain juices flowing 😎

Edited by Matthew Kane
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Hi Will,

 

You can easily update your flightsim navigation database at http://www.aero.sors.fr/  

It has an installer and backs up the original data.

Click on the Navdata tab. There is a worldwide database and a regional one for runway and ILS corrections for areas other than Europe. Fixes can also be updated on a regional basis.

The only real drawback is that it can mess up the flight planner and map functions in FS. However there are many other flightplanning tools available with easy to use maps and flight plan export functions such as Plan G, Little nav map, Vroute and Simbrief.

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