[Borns]

Hey guys,

In my 2008 3-series I could see my current altitude in navigation menu. I don't see it anymore in my new X3 (with navi professional)...

Is there a way to see it? It's quite important for me as I live in the mountains!

Cheers

[Le Chef]

I would buy a Tissot T-Touch which doubles as watch, compass, altimeter, etc.

[Borns]

I have Suunto, thanks Strange that they deleted this option...

[datrobmw]

In my 2012 X3 28i, I see latitude, longitude, and altitude when I enable "Display Current Location" in the Navigation menus.

[Harv_NC]

While I enjoy my Tissot as much as the next guy, you can get Altitude on your X3: On the split screen, change the information option. Can't recall the exact name, but its something like "Current Position". Gives Lat/Lon and Altitude

[April1]

Even 2011 X3 shows Altitude in split mode when set to position. Accuracy of altitudeay be low ~30' or more based on the satellite fixes.

[96_Impreza]

Elevation, unless the car is in an aircraft.

[Dr Stig 2]

Easy to calculate.

Get a sikorsky helicopter to lift your X3 up to 5,000 metres, then, using your Tissot, time the descent as it falls until it splatters on the ground.

From the time in seconds, simply do the following maths.

Elevation = 5000 - 0.5 x 9.8 x t^2



Note: This is not a long term solution. Might be easier to use the innacurate elevation measure from the GPS.

[Radioactive]

Originally Posted by Dr Stig 2

Easy to calculate.

Get a sikorsky helicopter to lift your X3 up to 5,000 metres, then, using your Tissot, time the descent as it falls until it splatters on the ground.

From the time in seconds, simply do the following maths.

Elevation = 5000 - 0.5 x 9.8 x t^2



Note: This is not a long term solution. Might be easier to use the innacurate elevation measure from the GPS.

I have a B-17 altimeter. Will that work on my wrist?

[Dr Stig 2]

Originally Posted by Radioactive

I have a B-17 altimeter. Will that work on my wrist?

In theory yes, but remember to check your calibration at sea level prior to departure.

[April1]

Originally Posted by Dr Stig 2

Easy to calculate.

Get a sikorsky helicopter to lift your X3 up to 5,000 metres, then, using your Tissot, time the descent as it falls until it splatters on the ground.

From the time in seconds, simply do the following maths.

Elevation = 5000 - 0.5 x 9.8 x t^2



Note: This is not a long term solution. Might be easier to use the innacurate elevation measure from the GPS.

If I have a way to measure 5000 m height, I don't need to lift my car.

[Borns]

Thanks for all the "relevant" replies! Will check it later...

[Borns]

Hmmm....Still can't figure out how to check altitude. Could someone, please, post step by step instructions? Step 1 - press navigation, step 2 - press options, etc, etc...

Thanks

[Borns]

Anyone?

[Harv_NC]

Yes...toggle over to the smaller screen (right hand side in US), choose split screen options, then choose Display Current Location. That should get you what you are after.

[Borns]

Of course! Very easy...
Thanks

[Valerio]

Originally Posted by Harv_NC

Yes...toggle over to the smaller screen (right hand side in US), choose split screen options, then choose Display Current Location. That should get you what you are after.

Harv NC. you state to chose Display Current Location. Is this on the same screen where you split screen. I don't see this phrase .

Valerio

[BMWrules7]

Originally Posted by Borns

Hey guys,

In my 2008 3-series I could see my current altitude in navigation menu. I don't see it anymore in my new X3 (with navi professional)...

Is there a way to see it? It's quite important for me as I live in the mountains!

Cheers

Just keep in mind that the altitude is probably based upon map data. In other words, your GPS provided your longitudinal and latitudinal coordinates. In turn, these coordinates are used to obtain the map data to reflect your location. It is from this relatively static location data that is used to obtain your altitude.

So, the quality and accuracy of your altitude data relies upon your accuracy (or inaccuracy) of your actual location obtained from GPS plus the accuracy of the altitudinal information stored within the map database.

Please correct me if I am wrong. But, your your GPS does not determine your altitude. It is the cross reference to the map data, based on location, that is used to provide your altitude.

[Chariotrider]

GPS devices triangulate in 3 dimensions. So they can calculate altitude as well as direction of travel and velocity.

[noka]

Originally Posted by Chariotrider

GPS devices triangulate in 3 dimensions. So they can calculate altitude as well as direction of travel and velocity.

Mine calculates in 4 dimensions, since it also tells me when I will arrive .

[MrFargo13]

Originally Posted by Dr Stig 2

Easy to calculate.

Get a sikorsky helicopter to lift your X3 up to 5,000 metres, then, using your Tissot, time the descent as it falls until it splatters on the ground.

From the time in seconds, simply do the following maths.

Elevation = 5000 - 0.5 x 9.8 x t^2



Note: This is not a long term solution. Might be easier to use the innacurate elevation measure from the GPS.

Excellent suggestion, Sheldon!

[RhoXS]

Originally Posted by BMWrules7

Just keep in mind that the altitude is probably based upon map data.

A GPS displays calculated altitude and does not use (if it even exists) stored data.

An altitude fix is not as accurate as a positional fix. It has been my observation over the years, with different GPS devices and automotive nav systems, that displayed altitude can rapidly vary upwards of a 100 or more feet while being stationary.

From the following link:

http://gpsinformation.net/main/altitude.htm


"New GPS buyers are frequently concerned about the accuracy (or lack of it) of the altitude readout on their newly purchased GPS. Many suspect their equipment may even be defective when they see the altitude readout at a fixed point vary by many hundreds of feet. This is NORMAL.

With most low cost GPS receivers, the horizontal error (without SA now that it is off) is specified to be within about +/- 15 meters (50 feet) 95% of the time. Most users find this is a conservative specification and that their modern GPS receivers routinely perform better than this worst case specification. But.. Users should expect that SOMETIMES they may see the error approach the specification limits. AND.. 5% of the time, the error may be "any value" from zero to whatever". Note: Unless you have a CLEAR AND UNOBSTRUCTED view of the sky (on your dash or looking out of an airplane window with no externally mounted antenna, or similar obstructed view does not count!) you can count on your error excursions to be much greater than the above numbers. Your GPS <depends> on this clear and unobstructed view or it cannot make accurate range measurements to the satellites.

Generally, Altitude error is specified to be 1.5 x Horizontal error specification. This means that the user of standard consumer GPS receivers should consider +/-23meters (75ft) with a DOP of 1 for 95% confidence. Altitude error is always considerably worse than the horizontal (position error). Much of this is a matter of geometry. If we (simplistically) consider just four satellites, the "optimum" configuration for best overall accuracy is having the four SVs at 40 to 55 degrees above the horizon and one (for instance) in each general direction N, E, W, and S. (Note: You will get a very BAD DOP if the SVs are at the exact same elevation. Luckily, this is a rare occurrence.) See: DOP demonstration site by Norris Weimer> How SV geometry affects GPS accuracy(Java Required).. The similar "best" arrangement for vertical position is with one SV overhead and the others at the horizon and 120 degrees in azimuth apart. Obviously, this arrangement is very poor from a signal standpoint. As a result, of this geometry the calculated solution for altitude is not as accurate as it is for horizontal position. Almost any calibrated altimeter will be more stable at reading altitude than a GPS.

GPS altitude measures the users' distance from the center of the SVs orbits. These measurements are referenced to geodetic altitude or ellipsoidal altitude in some GPS equipment. Garmin and most equipment manufacturers utilize a mathematical model in the GPS software which roughly approximates the geodetic model of the earth and reference altitude to this model. As with any model, there will be errors as the earth is not a simple mathematical shape to represent. What this means is that if you are walking on the seashore, and see your altitude as -15 meters, you should not be concerned. First, the geodetic model of the earth can have much more than this amount of error at any specific point and Second, you have the GPS error itself to add in. As a result of this combined error, I am not surprised to be at the seashore and see -40 meter errors in some spots. "