[bobkochs]

I have a new Outback Limited with the 3.6-liter engine, Eyesight, etc.
I love it, but I'd like to display the car's elevation, which I was able to do on my prior car, a 2015 Legacy Limited.
Any ideas? Thanks!

 

[johnre]

Speaking as a mountain climber - GPS is pretty good for latitude and longitude, but is weaker on elevation accuracy. I think that's why many units don't support an elevation readout.

Even though I carry a handheld GPS unit climbing, I also carry a wristwatch barometric altimeter because of this.

More here: Altitude Accuracy

 

[CoreyMac]

I agree. Vertical GPS has not been nearly as accurate in my experience as the GPS units themselves seem to believe. Proof of that is to note the range of vertical heights presented by a GPS when not moving at all. When stationary, I have seen several of them vary by +/-150 feet even though they declare their vertical certainty to be +/- 50 ft or less. Their averaged values are pretty good, but taking that many samples while stationary can take a while.

Many dedicated hiking/sporting GPS units have barometers to help with altitude data management and collection.

 

[Trip Enroute]

Wishing for an elevation readout... Me too.

I too was hoping someone had found a way to show elevation on the Navi. My 2018 Premium OB is the first vehicle that has a built in GPS. The Navi is (mostly) what I expected but for a vehicle targeted to "outdoor" folks, I would think the elevation readout would be a given. It has to be part of the GPS chip.

We are hikers/backpackers and kayakers. Having the elevation on the screen would be wonderful as we wander around in the backcountry. For years I have had my handheld GPS mounted to the dash so I could see the elevation. I need to find a way to mount the handheld again. While the Navi is fine for paved roads, what I probably really need is some version of a portable GPS with a large screen an topo maps. Anyone have any suggestions?

 

[Brucey]

The 2017 GPS has elevation displayed if you hit the location button.

Does the 2018 not have this feature?

 

[atc98092]

...
Many dedicated hiking/sporting GPS units have barometers to help with altitude data management and collection.

How would a barometer assist a GPS with accuracy? GPS uses radio signal triangulation for a three dimensional position fix. Atmospheric pressure would have zero impact on that calculation. we have to use 1000' (or more) vertical separation between aircraft because of the less than accurate altitude reported by traditional barometric altimeters.

On my 2018 I don't see a location button. I can touch the label at the screen bottom (believe it shows the street currently on), and it offers the lat/long and the ability to save the location, but there's no altitude shown.

 

[ammcinnis]

How would a barometer assist a GPS with accuracy?

Not to mention that barometric altitude indication varies with local atmospheric pressure ("altimeter setting"). At low altitude/elevation, a 0.5 inch-Hg difference in atmospheric pressure corresponds to roughly 500 foot error in indicated altitude. (There is a big difference between an altimeter setting of 30.05 and 30.50. Don't ask me how I know. )

 

[johnre]

How would a barometer assist a GPS with accuracy?

I'm not sure how they integrate the software to combine GPS with barometer.

Not to mention that barometric altitude indication varies with local atmospheric pressure ("altimeter setting").

No system is perfect, and you have to be aware of the limitations in each case. Note that hikers and climbers are moving much slower than aircraft, and they get many points of correction if they are carrying topos, such as mountain passes, stream crossings, trail crossings, summits, etc. That may not be possible if aircraft aren't assisted by ground-based radar.

Anecdotally, my wrist barometer seems quite a bit more accurate than my Garmin GPS.

 

[donaldedwards]

I am horrified by the terrible TomTom navigation in my '18 Outback.

It appears to be worse than useless and I will use smartphone nav apps.

My Honda had a built-in Garmin unit that was intuitive.

Subaru.

 

[ammcinnis]

No system is perfect, and you have to be aware of the limitations in each case.

Agreed.

Anecdotally, my wrist barometer seems quite a bit more accurate than my Garmin GPS.

Fake proverb: "A man with one watch knows what time it is. A man with two watches is never sure."

 

[AvidHiker]

The 2015 nav displays the name of the road you're currently on (but only if you're on a road) in a box at the bottom of the screen. If you tap that box, it brings up a screen showing elevation and approximate numbered addresses for each side of the road. Under good conditions, I've observed an accuracy of roughly +/- 100 feet. Don't use it much so not sure how reliable it really is.

I've always found my little analog barometer to be sufficiently accurate when hiking (comparing with a topo). The only thing that could throw it off would be a significant weather event, but not likely more than a few hundred feet over the course of a day, and a typical hike offers multiple opportunities to re-calibrate at known locations. I don't generally use GPS, but have observed them struggling for just a 2D position in certain types of terrain and/or vegetation.

 

[crazyfingers1]

The barometer build into hiking GPS's won't accurately get you the correct starting point altitude. What they are good at is detecting a change in altitude. Were I to really care about altitude on my hand-held, it would want me to enter my known starting elevation that can be next to zero if you hike starting at the seashore. Or look on the topo and enter in the elevation you are on the map. But once you start going up, (or down) the change in pressure will help the GPS estimate altitude better - assuming your weather doesn't change much.

 

[Trip Enroute]

The 2017 GPS has elevation displayed if you hit the location button.

Does the 2018 not have this feature?

No. Not on my 2018 Premium.

To clarify... what I want (which it doesn't have) is a continuous elevation readout of where I am. I find that entertaining especially on a backroad trip through the mountains to say...Dolly Sods or Seneca Rocks.

 

[Brucey]

No. Not on my 2018 Premium.

To clarify... what I want (which it doesn't have) is a continuous elevation readout of where I am. I find that entertaining especially on a backroad trip through the mountains to say...Dolly Sods or Seneca Rocks.

Dolly sods is lovely. We backpacked for 4 days there last summer.

On the 2017 if you click the road name / location it shows GPS Co-ordinates and Altitude.

It's strange that they would remove that feature.

 

[atc98092]

Not to mention that barometric altitude indication varies with local atmospheric pressure ("altimeter setting"). At low altitude/elevation, a 0.5 inch-Hg difference in atmospheric pressure corresponds to roughly 500 foot error in indicated altitude. (There is a big difference between an altimeter setting of 30.05 and 30.50. Don't ask me how I know. )

We can always tell if someone has their altimeter set wrong, because they won't be at the altitude they are supposed to be at. In level flight, our scopes allow +/- 200 feet before showing high or low. Plus, our display is rounded to the nearest hundred foot.

 

[atc98092]

I... Note that hikers and climbers are moving much slower than aircraft, and they get many points of correction if they are carrying topos, such as mountain passes, stream crossings, trail crossings, summits, etc. That may not be possible if aircraft aren't assisted by ground-based radar.

...

Radar has nothing to do with their ability to maintain altitude. All it does is provide a data path (via the transponder) between the aircraft and the ATC computers to display their altitude. They've used altimeters since long before radar and GPS. But in the aircraft there is no interaction between the GPS system and the altimeter.

 

[crazyfingers1]

No. Not on my 2018 Premium.

To clarify... what I want (which it doesn't have) is a continuous elevation readout of where I am. I find that entertaining especially on a backroad trip through the mountains to say...Dolly Sods or Seneca Rocks.

The Garmin on my dash does that or will do that if I set one of the data fields to show that instead of some other item. But mainly I use the data field for other things like distance to destination or something.

 

[Tishers]

To get a 2D fix the GPS system needs to be able to reliably lock on to at least three satellites. For a 3D fix that includes elevation it needs to be able to lock on to at least four.

If you look at where the GPS antenna is mounted on a late model it is under the dashboard, approximately where your right hand would be if you extended it outward and set it down on top of the dash.

The satellites are transmitting a signal at 1.575 GHz (microwave) and although the signal still gets through it is attenuated by the windshield glass and the plastic on the dashboard. Additionally the little antenna does not have a totally clear view of the sky, the roof of the car shields almost 1/2 of its visibility to the sky.

I do not know if the nav system is WAAS enabled (for more precise location services) where it also can support earth-transmitters for precision location. More expensive systems (like aircraft equipped with approved GPS systems) do use WAAS and some even use other frequencies that the GPS satellites transmit so they can pinpoint location down to centimeters.

Have you ever noticed how sometimes your map location will jump or you will sometimes be tracking parallel to the road? That is the kinds of things that happen when the system is not locking on to enough satellites, the precision can drop down to +/- hundreds of feet. Also, if the nav system puts you a hundred feet off to the side it may just decide that you are "offroad" and the nav system just stops providing directions as it recalculates and recalculates and finally says "no route found". Then a few minutes later or miles down the road it jumps on to some side street and gives you something completely wacky.

If a pilot was completely irresponsible they could depend upon GPS to practically put them down on a particular white stripe on the center of the runway every time. Thank goodness they use their common-sense and a pair of mark-I calibrated eyeballs.

 

[johnre]

If a pilot was completely irresponsible they could depend upon GPS to practically put them down on a particular white stripe on the center of the runway every time. Thank goodness they use their common-sense and a pair of mark-I calibrated eyeballs.

There are GPS jammers and signal spoofers out there that can render GPS ineffective or worse. So yes, it pays to know how to navigate the old fashioned way.

Mountaineering courses still teach navigation with a compass and topo map for this reason.

 

[AvidHiker]

No. Not on my 2018 Premium.

To clarify... what I want (which it doesn't have) is a continuous elevation readout of where I am. I find that entertaining especially on a backroad trip through the mountains to say...Dolly Sods or Seneca Rocks.

So, while it may not be ideal, we've now established that both the 2015 and 2017 navs will give a continuous readout of elevation by tapping the road name at the bottom of the screen, but no specific response from you as to whether or not you've tried this on your nav. Are you saying this method doesn't work on the 2018 unit?