I would like to be able to use my Garmin etrex (that my wife uses for geocaching) in the air. I noticed however, when I go to Airnav.com that the coordinates for airports are listed in 3 different ways and all with way too many numbers after the decimal to fit on my GPS. I also haven't tried this gps yet in the air, but it does have WAAS. Of course, it doesn't have moving map or anything like that, but it does show direction, heading etc and distance to point or waypoint. Does anyone know anything about why the airports don't use normal coordinates? Would like to avoid buying a Garmin Aero 500, but maybe I will need to?
Cheap GPS
- Thread starter Kirbhund
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AggieMike88
Touchdown! Greaser!
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The original "I don't know it all" of aviation.
Some smart phones that have GPS chips also have apps that can do the position recording.
ziege
Pre-takeoff checklist
Airnav lists coordinates in DMS (degree, minutes, seconds e.g. 38-53-23.6989N / 090-02-45.5567W...38 degrees, 53 minutes, 23.6969 seconds north....), DM.M (e.g. 38-53.394982N / 090-02.759278W) and decimal degrees (e.g. 38.8899164 / -90.0459880).
You want the second option. In the air you aren't going to care about all that precision either. Toss the rightmost digits and you'll do fine. So 38-53.394982N becomes N38°53'. Alternatively look at the A/FD which will give you something like this: N38°53.39' W90°02.76' ... again, degrees and minutes but decimal minutes.
Your eTrex's position format is configurable. Mine (which I don't use in the air, but still) defaulted to degrees and decimal minutes (ddd°mm.mmm' or something like that). The same as the A/FD I believe. No problem to use.
If you want to use the eTrex in the air, write down the lat/lon of all checkpoints during flight planning. Then, when you are in the air, use the difference between checkpoint and GPS fix to figure out how far from the checkpoint you are. So if your checkpoint is N38°53' W90°02' and your eTrex shows N 38°52.921 W91°48.107 that says you are just a hair south of your checkpoint but west by a huge amount (about 80nm)...
I know of no reason NOT to do that, except it might distract you from using more conventional nav tools like your eyeballs or radio nav.
You want the second option. In the air you aren't going to care about all that precision either. Toss the rightmost digits and you'll do fine. So 38-53.394982N becomes N38°53'. Alternatively look at the A/FD which will give you something like this: N38°53.39' W90°02.76' ... again, degrees and minutes but decimal minutes.
Your eTrex's position format is configurable. Mine (which I don't use in the air, but still) defaulted to degrees and decimal minutes (ddd°mm.mmm' or something like that). The same as the A/FD I believe. No problem to use.
If you want to use the eTrex in the air, write down the lat/lon of all checkpoints during flight planning. Then, when you are in the air, use the difference between checkpoint and GPS fix to figure out how far from the checkpoint you are. So if your checkpoint is N38°53' W90°02' and your eTrex shows N 38°52.921 W91°48.107 that says you are just a hair south of your checkpoint but west by a huge amount (about 80nm)...
I know of no reason NOT to do that, except it might distract you from using more conventional nav tools like your eyeballs or radio nav.
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COFlyBoy
Line Up and Wait
I got the eTrex serial cable and used EasyGPS to load lists of waypoints into the GPS. Then you can use it as a VFR aviation GPS. I got the waypoints as a GPX file from here: navaid.com
I relied on my Etrex for long range navigation, but I had to be at my destination to put in the waypoint. It was good for getting there the second time, but the first time I had to find it the old fashioned way. I follow roads.
Cap'n Jack
Final Approach
Use the Mapsource program from Garmin to upload waypoints.
To get the aviation data, go to http://navaid.com/ and select the GPX link. Follow the instructions and you'll have a VFR aviation database GPX which you can import into Mapsource; depending on the amount of data, this may take awhile.
After you get the data, use the waypoints to make a route that you upload to your e-trex. You can also upload other waypoints, such as airports close to your route.
if you are an AOPA member, another way to get routes into your e-trex is to use their flight planner and export the file as GPX and pick it up in Mapsource. Use Mapsource to send the route to your GPS.
Both of these work for pretty much any Garmin GPS, even those for cars. I suggest Mapsource because you likely have the software, but anything that reads GPX and speaks to your Garmin will work.
To get the aviation data, go to http://navaid.com/ and select the GPX link. Follow the instructions and you'll have a VFR aviation database GPX which you can import into Mapsource; depending on the amount of data, this may take awhile.
After you get the data, use the waypoints to make a route that you upload to your e-trex. You can also upload other waypoints, such as airports close to your route.
if you are an AOPA member, another way to get routes into your e-trex is to use their flight planner and export the file as GPX and pick it up in Mapsource. Use Mapsource to send the route to your GPS.
Both of these work for pretty much any Garmin GPS, even those for cars. I suggest Mapsource because you likely have the software, but anything that reads GPX and speaks to your Garmin will work.
Mike_Flys
Pre-Flight
Incase you decide you want to buy an Aviation GPS:
I like Garmins but don't consider them low dollar.
Thanks to my wife I have a "Adventure Pilot iFly700" GPS.
It is a great bang for the buck.
Mike