I've just received my brand new Mavic Air!!! After fully charging all of the batteries and remote controller, I've begun the firmware update. However, how long should this take. It's been updating for over an hour! The battery still has two remaining green lights and the remote controller 3. Is this normal? What happens if the batter fails before the firmware update is complete?

It's not normal. It only took me 10-20min total. Is the progress bar stuck? If so, is it stuck at downloading or updating?

15-20 mins max for download and installation is typical. Are you using DJI Assistant 2?

I have the same problem.  Mine gets stuck on the updating portion.  Tried many many many times.....  

This is how I fixed it.  Contrary to what the software instructions tell you... turn everything off and reconnect and it will work like a charm

I also have the same problem. Tried many many times. The progress bar doesn't show any progress, it stays at 0% progress.

I'm updating right now and has failed the firmware update multiple times at 20%.  I believe I'm on my 5th or 6th attempt.  I'm updating from the DJI GO 4 App.   Wait....I'm at 58% now...this time it may work.  Crossing my fingers......

At 86% still crossing my fingers....

Aircraft now rebooting......restarted.....

This update also includes:
Dated 1-27-2018
Aircraft Firmware :  v.1.0.1.0
Remote Controller Firmware update (vs 1.0.0.0)
DJI GO 4 App iOS:  v4.2.5 (which I'm using)
DJI Go 4 App Android:  v4.2.4

At 93% now.......

At 99% now....Aircraft rebooted a 2nd time...

Still at 99% after reboot

UPDATE COMPLETE!  Nice!! Finally worked...but took several attempts...Full firmware update took about 10-15 minutes when it didn't time out.

RGMGFitness Posted at 2018-2-8 19:49
I'm updating right now and has failed the firmware update multiple times at 20%.  I believe I'm on my 5th or 6th attempt.  I'm updating from the DJI GO 4 App.   Wait....I'm at 58% now...this time it may work.  Crossing my fingers......

At 86% still crossing my fingers....

Hi there, are you trying to update the aircraft/controller via DJI GO 4 or DJI Assistant 2? I'll attach the tutorial videos for double check. If both fail, please refer below and export the update log for analysis, thanks!
Assisstant 2(Windows) C: /Users/XXXXXX/AppData/Roaming/DJI Assistant 2/upgrade_log
Assisstant 2(MAC): ~/Library/Application Support/DJI Assistant 2/upgrade_log
APP(IOS): Click the DJI logo on the left upper corner more than 10 times, you will see the log and copy it to us
APP(Android): dji/dji.go.v4/log/cache/up_new_all
       

So my firmware update stopped at 30% too.  Waited about 30 minutes and then after reading this post I decided to just stop and restart my DJI Go 4 app on my smartphone.  After restarting the app I started the firmware update again and this time it completed in like 10 minutes!  

I updated using phone connected to RC everything works fine.

My advice: Dont  give up. When you finally get up in the air, you will love it.

Hi Mavic owners, when I connect my Air controller to my laptop and power on the controller, it won't connect to Laptop so I cannot update the controller firmware........any advice would be appreciated.

Just experience stock at installing at 99% on my RC update until I notice that during progress the RC usually turn off/on  connection for updating process.. also the cellphone usb connections sometimes it resets its data connection to charger instead of file transfer so I manage it to set my micro usb connection from my cellphone to data file transfer then... Oh Good GOD it was fast and completed! PTL!