I flew my Mavic Air 2 tonight for the first time at night. I sent it up to about 150 feet, flew it around my neighborhood for about six minutes with no problems, and then hit the Return To Home button.
Every time I fly in the daytime it returns exactly where it lands but on this night flight it deviated from it's take-off spot by ten feet.
A window popped up on the screen  saying two things:

1) The drone reached it's maximum potential. Descend and fly with caution. If the problem persists, land immediately.

2) The surroundings are too dark. Vision System not available. Fly with caution.

The drone almost clipped the eaves of my house as it landed but I caught it in time and maneuvered the levers to get it down. My patio light was on, so it was not pitch dark.
I thought that the Return To Home feature used technology that enables it to land in light or dark. Every video on YouTube I've seen about flying the Mavic Air 2 at night made flying at night seem to be no different than the day as far as RTH and landing it goes.

Does something special need to be done for night flying in relation to bringing it back in with RTH?

RTH still requires a good GPS signal, and there are times when few satellites will be visible in the sky or when environmental factors like sun activity degrade the precision. When that occurs, the location that the drone may return to a spot that is some distance away from the takeoff location.

I don’t think the Precision Landing feature really works in low light, the small LED simply doesn’t have enough output to provide enough light to illuminate the ground from several yards up. That would be especially true for dark surfaces like grass. The light isn’t just used for gauging elevation, but also for matching the area against an image taken during takeoff. Last but not least, there needs to be something distinctive for the drone to latch onto, like a drone landing pad. A patch of grass that looks like every other patch of grass nearby doesn’t help the precision.
I'm not saying the Precision Landing feature can't work in low light, but it requires a good GPS fix and a distinct surface to work.

Agreed - GPS will obviously be unaffected but the OA will not work effectively. You will need to know the flight area

Hi. I am sorry for the trouble this has caused. With regards to this matter. Please fly with caution during night time since the Precision Landing needs enough lighting to scan and match the terrain from the HomePoint's terrain for a safe landing. For reference for the Precision Landing please refer to the image posted below. Thank you.

I'm actually impressed to hear it returns to the same exact spot every time you fly it during the day. For me, precision landing works rarely, maybe 1/10 flights. I am always taking off straight up to at least 30ft but it's almost never finding the landing pad on its own. The issue doesn't seem to be with the precision landing feature itself, but with GPS positioning. Precision landing only seems to work if GPS brings it up within a reasonable distance of the landing pad, like 5 feet. If the GPS was not that accurate on takeoff (although I always wait for at least 9 satellites and good reception before taking off) and it brings it back like 15ft from the landing pad, then precision landing won't work and this is how it is for me most times.  

Does something special need to be done for night flying in relation to bringing it back in with RTH?

Yes, all drone flyers should be in full control of their drones at all times even when RTH automatically.  Precision landing is a bonus but who needs it when always have VLOS and control of your drone as you are required to do.  Never fully trust your drone at night in the pitch dark, it is unpredictable.

Ice_2k Posted at 7-23 04:55
I'm actually impressed to hear it returns to the same exact spot every time you fly it during the day. For me, precision landing works rarely, maybe 1/10 flights. I am always taking off straight up to at least 30ft but it's almost never finding the landing pad on its own. The issue doesn't seem to be with the precision landing feature itself, but with GPS positioning. Precision landing only seems to work if GPS brings it up within a reasonable distance of the landing pad, like 5 feet. If the GPS was not that accurate on takeoff (although I always wait for at least 9 satellites and good reception before taking off) and it brings it back like 15ft from the landing pad, then precision landing won't work and this is how it is for me most times.

Really? It works for me almost every time. I use a 30" landing pad and it almost always comes down on it in the center. The only time it did not quite make it was when I had hovered only about 15 feet up (instead of 35') and there were large trees all around that were probably not recorded.

Ice_2k Posted at 7-23 04:55
I'm actually impressed to hear it returns to the same exact spot every time you fly it during the day. For me, precision landing works rarely, maybe 1/10 flights. I am always taking off straight up to at least 30ft but it's almost never finding the landing pad on its own. The issue doesn't seem to be with the precision landing feature itself, but with GPS positioning. Precision landing only seems to work if GPS brings it up within a reasonable distance of the landing pad, like 5 feet. If the GPS was not that accurate on takeoff (although I always wait for at least 9 satellites and good reception before taking off) and it brings it back like 15ft from the landing pad, then precision landing won't work and this is how it is for me most times.

According to page 15 of the User Manual,

During takeoff, the aircraft must ascend vertically 7 m before moving horizontally for precision landing to be activated.

fans2dfd5118 Posted at 10-12 10:50
According to page 15 of the User Manual,

During takeoff, the aircraft must ascend vertically 7 m before moving horizontally for precision landing to be activated.

Thats not the only variable needed too - correct lighting conditions, clean sensors, home point on the map before take off, not changing the home point in flight, not altering the take off point and having a clearly distinguishable feature for the home point such as a landing pad that is a different tone to the surrounding area i.e. an orange pad on green grass - all of these variables affect the effectiveness of the precision. I also find it to be more on point/accurate when not recording video on the return.

A J Posted at 10-12 10:56
Thats not the only variable needed too - correct lighting conditions, clean sensors, home point on the map before take off, not changing the home point in flight, not altering the take off point and having a clearly distinguishable feature for the home point such as a landing pad that is a different tone to the surrounding area i.e. an orange pad on green grass - all of these variables affect the effectiveness of the precision. I also find it to be more on point/accurate when not recording video on the return.

In Europe flying during the night is forbidden!

dirkbertie Posted at 10-12 11:29
In Europe flying during the night is forbidden!

Not if you have permission to do so

fans2dfd5118 Posted at 10-12 10:50
According to page 15 of the User Manual,

During takeoff, the aircraft must ascend vertically 7 m before moving horizontally for precision landing to be activated.

yeah, I'm doing all that but it's still a bit hit & miss. The visual positioning part works fine, it's just that sometimes, even if I take off with 14-15 locked satellites, the GPS location is not yet that accurately determined and it's actually something like 5m away. When coming back from landing, if it's that far off from the landing pad, it won't be able to correct itself. If the initial GPS-based approach is 2-3m max from the HP then yes, it will land spot on the landing pad, dead center. Anyway, not that important tbh, it's just cool but not that useful

fans2dfd5118 Posted at 10-12 10:50
According to page 15 of the User Manual,

During takeoff, the aircraft must ascend vertically 7 m before moving horizontally for precision landing to be activated.

I think the actual wording should read "...must ascend vertically AT LEAST 7 m...". Seven meters rarely works for me because of surrounding higher objects. Ten meters works fine.

GaryDoug Posted at 2020-7-23 18:18
Really? It works for me almost every time. I use a 30" landing pad and it almost always comes down on it in the center. The only time it did not quite make it was when I had hovered only about 15 feet up (instead of 35') and there were large trees all around that were probably not recorded.

I bought a landing pad with lights.
Its a circle landing pad with red light around the outside circumference of the circle.  Do you think this would help for auto return at night?

Paul Trombley Posted at 3-10 19:58
I bought a landing pad with lights.
Its a circle landing pad with red light around the outside circumference of the circle.  Do you think this would help for auto return at night?

Maybe. Let us know if it works better.

GaryDoug Posted at 3-10 20:02
Maybe. Let us know if it works better.

From my take off spot I created a little airport. 20ft perimeter surrounded by LED spot lights . . 4 cheap ones I got on Amazon. Battery powered. Works like a charm. I try not to not fly in pure darkness. Lost 1 drone (eaten by a tree) and crashed one with little damage. Since then I setup my night airport. But... there are still many risks. Seems like Trees have longer arms at night and they love drones.

I would simply cancel the RTH once the drone is overhead, then manually land it.

dirkbertie Posted at 2020-10-12 11:29
In Europe flying during the night is forbidden!

In Belgium it’s allowed. You need to respect the rules as always. And just need an extra green strobe light.  

Have you followed any instructions or did you just tried to spot a drone yourself?
I guess your RTH just needs a better GPS signal. It may not work also because of the low light, which is obvious because you tried it in the middle of the night. I recommend you to check this article on how to spot a drone at night and see if it’s fine. I believe that something might have gone wrong when you tried to do it yourself the first time.

Can the auxiliary LED be damaged when used during whole flight? I know high-powered LED's can become pretty hot and could burn-up pretty easy if not cooled properly. Since the aux LED does not have a heatsink, can it be damaged when used for long periods of time? Or it's not that high-powered?

Landing precisely at night isn't as foolproof as it is in daylight. That's because our drone's eyes, so to speak, rely on light to function their best. But don't worry, there are a few tricks up your sleeve to up your odds of nailing that nighttime landing:  1. Find yourself a landing spot that's well-lit. 2. Double-check there's nothing blocking your drone's path to the landing zone. 3. Always take off and touch down from the same place. 4. Utilize a nifty drone landing pad for added stability.  Now, if our drone can't quite see in the dark, it'll default to its GPS for the journey home. Mind you, this backup plan might not be as spot-on, especially when the lights are low. To make your night flights a breeze, here are some bonus tips:  - Keep your peepers peeled and fly within sight (VLOS). - Steer clear of gusty winds for a smoother ride. - Consider using a battery warmer to keep things toasty. - Take it slow and steady when you're setting her down. You can also read this article if you want to get more information: https://skbestgadgets.com/can-you-fly-dji-air-2s-at-night/