Since the MM is a prodigious little marvel (when it works) and because flying inside abandoned buildings is one of the things I've thought of doing when I've bought my Mini I quickly stumbled onto the reality of the possible loss of signal scenario.
Despite not planning to stay very far from the Mini sometimes the need to inspect a building completely out LoS may arise. For What I've seen walls should offer enough reflectance for part of the Wi-Fi signal to be bounced off, and part of it being passed through. But what will it happen if the remote signal is lost ?

The manual isn't very clear about RTH while GPS is not available, Smart RTH shouldn't take place, but what about Failsafe RTH or Low battery RTH ? Besides who can't exclude the Mini will have a good GPS lock even inside a building ? The routes to the unknown are yet to be explored... but before going any further, it would be very nice to have a feature implemented.

I'd like a way to disable Failsafe RTH and Low battery RTH and possibly having a Smart RTH traceback, using the IMU sensors alone to bring back the Mini to the point it started from. Since I have experience with the kind of precision an IMU logics can have on a mobile device I am 100% positive such logic could be implemented on the Mavic Mini to aid pilots explore more comfortably confined spaces without the risk of losing the drone if a normal RTH scenario happens.

Whether DJI would even consider this options is just speculation... I think it's a bit irrealistic thinking they'd start doing it for the Mini, but it would be nice and possible to have this option and I feel something that could save many Minis from smashing into something when flown in confined spaces.

I think a much more realistic possibility is for them to add the failsafe options the GO4 app have, meaning you would be able to tell the Mini to simply hover in place once signal is lost instead of trying to RTH.

Hover is definitely the solution for indoor flying.

DAFlys Posted at 1-28 01:52
Hover is definitely the solution for indoor flying.

Surely land would be the better option, if you hover and can’t  regain signal you will have to wait for low battery. With mini if you can keep within 20m 60ft in any building it will just land .

It is a good remark @hallmark007 but providing you're under GPS coverage. I am wondering whether it would still happen in ATTI mode w/out GPS lock or outside the 20m radium w/ GPS lock.

I'm not sure I would prefer my Mini to just land, especially in the context of exploring abandoned buildings. It might land on a flight of stairs and tumble down, it might land in a puddle or a turd. Either way, having the option to set this behavior in advanced like in the Go4 app seems like the best choice.

m80116 Posted at 1-28 03:04
It is a good remark @hallmark007 but providing you're under GPS coverage. I am wondering if would still happen in ATTI mode w/out GPS lock or outside the 20m radium w/ GPS lock.

Yes it will land, with weak gps ie atti mode, the biggest problem with old buildings is they are usually devoid of light so first no gps and no optical vision so your left with atti mode. For Ice your drone will not land in a puddle or muck or on uneven ground that’s what your sensors are for and if there not working you will be glad it lands in a puddle instead of banging into a wall, because if optical sensors are not working then that’s exactly what will happen if you lose signal .

hallmark007 Posted at 1-28 02:58
Surely land would be the better option, if you hover and can’t  regain signal you will have to wait for low battery. With mini if you can keep within 20m 60ft in any building it will just land .

Depends what your flying over I think,  if you were over water or a stair well landing could be very bad.

DAFlys Posted at 1-28 05:56
Depends what your flying over I think,  if you were over water or a stair well landing could be very bad.

Your craft has sensors that are used to find safe place to land these include water, so if they’re working your craft shouldn’t land in water or on uneven surface .We don't have hover as an option on mini but landing is not a bad option.

Hello and good day m80116. Thank you for sharing your insights with regards to this matter and for sharing these information with us. These information will be cascaded to the designated DJI department for further attention and evaluation. Thank you for your support.

Ice_2k Posted at 1-28 01:08
I think a much more realistic possibility is for them to add the failsafe options the GO4 app have, meaning you would be able to tell the Mini to simply hover in place once signal is lost instead of trying to RTH.

Traceback without GPS seems rather difficult, not sure if any DJI drone has that capability.
Having the option to hover in place when signal is lost seems an easier and more realistic option, especially in situations where you are not far from the AC and can hopefully change position until you regain signal. In the particular scenario envisioned by the OP (flying inside abandoned buildings), I personally would not want the MM to try and land when it loses signal, as I think the risk of hitting something would be quite high. Better stay where it is, and let the pilot get closer and back in control. If that doesn't happen, then of course land.

are we asking to have this drone copy some of the features found in other drones?