No flight mode???

No, it is not there. I don't understand it either. It is on almost every Garmin FR and Fenix but not on their lifestyle watches. Something really small with big impact. 

I am with you 100%, also use airplane mode all the time when not needing BT, Wifi or ANT+. 

Garmin, where ist it? This, and pausing an activity for longer time "save for later", are two big missing features which no one can explain really why. 

Zange said:

two big missing features which no one can explain really why. 

It's called product differential. If a customer wants a specific feature, they have to upgrade and pay a little more.  It makes perfect sense from a business point of view.  Now I know there will be people who'll say "it's really not something that big that will cut into sales of other watches".  My response would be to what end?  Who decides what features are added to each watch other than Garmin?  If it were the customer's choice, every Garmin device would share the same features and we wouldn't have an option of an outdoor, multisport, or lifestyle watch.  They'd all be the same. 

I am totally with you when it comes to features like training metrics, I even understand recovery time even though that is essential for more than runners etc. I understand, the more you pay, the more you get. But sorry, airplane mode and save for later has nothing to do with metrics or anything really sport related besides pausing it during a hike f.e.. Airplane mode not even with anything related to sport. And it is available on most watches much less expensive the Venu, so it has nothing to do with upgrading any paying more. And nothing with training specifically either. 

So normally yes but with these specific stuff it has nothing to do with upselling. 

I don't have a Venu 2 device or a Venu but so simple thing should be possible I think.

WLAN is always off as long as you don't have an activity waiting to be synced and even if auto sync via WiFi is disabled.

There is a help manual page for Venu that says how to turn off Bluetooth connection with the watch. https://www8.garmin.com/manuals/webhelp/venu/EN-US/GUID-139CD52F-B25F-4002-B13D-ACF7FEA70A04.html

So isn't it the same or similar in Venu 2?

I have a Venu 2 and the setting that sis651 just mentioned is also there on the Venu 2 to turn off the Bluetooth.  Also the Wifi is normally off, also as sis651 wrote above. 

Of course I know how to turn off Bluetooth but I didn‘t know that WLAN is off if there isn‘t an activity to be synced.

Then I assume that I only have to deactivate Bluetooth because WLAN is off anyway and GPS is on only during an activity...

Well, you were right though. ANT+ and others are not turned off completely only because BT is off. Of course normally WiFi is not syncing but it is on standby. And ANT+ the same. Those ANT+ sensors can only be turned off by airplane mode. And I don't believe there is no radiation or similar around the device when BT is off. I don't understand why airplane mode is in almost every Garmin watch but not Venu or Vivoactive line. 

No worries and no big necessities for the airplane mode.

Ant+ sensors won't be turned off just because you put your watch in some airplane mode. Almost all ANT+ sensors are transmit only and works in receive mode in special conditions like firmware update etc. Other than that, they only transmit data. So even if you put your watch in airplane mode or even if you switch it off, your chest heart rate sensor will continue to broadcast your heart rate inside the plane, if you wear it. Tempe sensor will continue to broadcast the temperature almost continuously unless you take its battery off. Even, you can stick it somewhere outside the plane and you'll be able to track outside temperature in your watch. :D I know people flying to bicycle races with Tempe sensors in their bags. Nobody even realizes there are actively broadcasting sensors inside. No plane has gone down yet.

So to summerize.

You can easily disable Bluetooth connection.

Headphones etc. are disconnected and watch won't be looking for them unless you search them inside the sensors menu or you want to play some music.

WiFi connection works only if you set some WiFi networks in your watch and you have some data to be synced and at the same time if WiFi auto sync is ON. If WiFi auto sync is disabled, it won't enable WiFi yet. Some apps may want to enable WiFi to transfer some data. However, you'll probably know these when they want to.

All ANT or BLE sensors are disabled when you're not in an activity. If you initialise an activity inside the plane, the watch will look for the sensors it's paired to. However, it'll just listen if they're ANT+ sensors. BLE sensors will require some traffic.

GPS and other GNSS is only enabled when you launch an activity and this happens in listening mode too. It doesn't transmit any data.

So basically, you're good if you switch Bluetooth off and don't try to run inside the plane and recorded. These watches are built around many power saving capabilities, so they won't be transmitting any unnecessary signal unless it's needed.

It maybe true that sensors are still sending but not the watch in airplane mode and it isn't receiving. When I turn on airplane mode on a FR or Fenix, sensors can't connect to the watch anymore. It is off.

And it isn't about airplanes, it is about radiation etc. And Wifi f.e. can't be turned off. So are you saying it has no radiation just because it may not sync at that very moment? Sorry, but Wifi sensors to my knowledge always send some kind of radiation. And airplane mode is not just BT off, it cuts many sensors completely off and reduces radiation by a lot more. And why should it be on FR and Fenix but not on Venu and VA series? What is the reason behind it?

And why was it a thing first in the Instinct tactical to cut everything off, at least so Garmin said back then in marketing, to make "you" aka the watch invisible when in hiding mode etc. outside? F.e. army use etc.? 

And you should say, sorry, that it is unnecessary. It may be for you, also of false reasons, as your answer is not all true and reality. But to others it is important.