Elevation not working on Apple Watch Ultra 2

This is consistent with what I am seeing. I too will contact Apple Support and see what can be done. I will mention that others are seeing the same problem and that for those who want to use this watch for trail running, mountain scrambling and ultras as I do, it is currently not working and could even be unsafe.

Runs are tracked using altimeter, GPS and cell tower information. But cell tower requires triangulation and GPS requires 4 satellites to determine altitude. This leaves altimeter which may not be accurate at times. Various environmental conditions may cause inaccurate or no measurements at all.

The altimeter 'should be able to work on its own' without cell info in the meantime. That's how all garmins etc work (before the advent of cell reception on watches). The vertical error of the gps is also greater than horizontal errow so by right it should defer to data obtained from the altimeter? What is problematic in the 'old days' is the need to continuously calibrate it due to the inherent changes in air pressure. By right a watch like a cellular apple watch can solve this by pinging pressure info as the run progresses (though I'm not sure the algorithm actually uses something like this.)

Anyway the built in altimeter of the apple watch is actually very accurate. That's why one can go up and down the stairs indoors and see the numbers actually changing, to the meter. (The gps is not used in this sort of elevation gain.) My particular issue is that my elevation is correct for around 30 minutes. But after that, it just goes haywire and goes up and down a lot even on flat terrain. In the end the accumulative 'elevation gain' is totally wrong for a say 30km run; something like 1000m which should actually be around 100m.

My understanding is when a running workout is started the altimeter takes a reading and another reading at the end. Cell tower information is used the majority of the time with GPS to determine location on run and altitude. Conditions can change and satellite reception be lost. Cell towers can go in and out of range. This produces less than desirable results.

Your reference to climbing stairs, which does use altimeter and arm motion and time measurements is also problematic indoors because of controlled climate, which fails to register the necessary change in altitude to trigger a flight of stairs climbed. The forums have many more posts about climbing stairs than inaccurate running measurements.

Try running with the compass app and see if the altimeter is changing while you run. Several third party altimeter apps also provide the means to calibrate the altimeter for more accurate readings.

No, the altimeter continuously monitors air pressure and I assume there may be GPS corrections. I use my watch where there is typically no cellular or internet. The altimeter works. Where do you get your information? Have you ever used the watch in the wilderness?

Yes, I frequently backpack in Yellowstone P and the surrounding National Forests. Altitude measurements happen fairly accurately, but not all the time.

I suspect small particles, sweat or outwear may at times interfere with accurate readings. I also notice people wearing protective cases that may interfere with accurate readings.

I did not inquire whether Apple is monitoring these posts. You have routinely provided incorrect and misleading information regarding how altitude is determined stating cell towers are required, etc. I am a field tester for Suunto watches, similar to Garmin. I have a fairly deep understanding of how altitude and elevation changes are determined on Suunto watches. Apple Watches with built in altimeters use similar or the same hardware. The major issue for pressure-based altimeters is determining whether changes in pressure are due to changes in weather or altitude. Various calculations are used for this including how fast the pressure is changing. Correction of absolute altitude can use GPS, which requires a very good fix and accuracy as GPS for consumers may not be accurate (this is intended as military has much better accuracy). The L1 and L5 dual band on the Ultra should allow better GPS correction for absolute altitude and Apple may use cell towers for this as well. However, the elevation changes while exercising will likely rely solely on changes in air pressure. Many of us reported here dropouts that should not occur and are most likely due to a software issue. My dropouts seem to have been corrected by beta firmware.

Interesting, several white papers on GPS and SA (selective availability) state the system was turned off in 2000 or 2001 as I recall. The errors are now, in most cases, reduced to a few feet. Errors now are more related to weather, atmospheric conditions and multipath issues.

Cell towers however have exact altitude measurements and with three or more towers both location and altitude can be determined.

Yes, software and firmware can resolve issues. But the majority of users don’t seem to have issues with altimeter. I know multiple pilots that state their watches are very accurate when the third party apps are calibrated, but Apple altimeter less so, because of lack of proper calibration.

What I find interesting is the Apple Compass app will show continuous altitude readings that appear quite accurate when I compare them to a USGS topographic map and a benchmark. Yet, at the same time the hiking workout is much less accurate. Why? Perhaps lack of cellular signals? You tell me.

I once used WorkOutDoors to measure my run and the altitude never dropped but in places it was off by 300-400 feet which I have not seen with any of my other watches. Other places it was accurate. I will emphasize that I have used two Garmin watches, one Coros watch, one non-cellular Apple Watch 9, and two cellular Apple Watch Ultra 2 watches. I always used Ultra 2 and another watch at the same time. The only watches that dropped elevation were the two Ultra 2s. No other watch has ever had any problems including the Apple Watch 9.

They use different sensors, different algorithms and different methods of calculating altitude. Let’s compare Apples to oranges.

I agree one may be more accurate than the other. Use the one that best suits your needs. I’ve been on other watches forums. I find the same discussions. Watch X isn’t as accurate as Watch Y. Go to another forum and it’s the opposite.

No one Watch is perfect or best choice for every user. Reading and watching reviews and forums will drive anyone insane. Pick you watch and try it. If you’re not happy, return it during the merchant’s return period and then try a different watch.

Today using a different app elevation never dropped out. I will contact Apple but I seriously doubt a hardware issue. I had a different issue where the app paused. Not a watch problem.

Understood. Let us know. Thanks.

Axel F.