What happens if you lose connection under a bridge?

[black_magic100]

Will the RTH function kick in and the drone just fly up and smack the bottom of the bridge since it doesn't have any sensors on the top? Is it a good idea to keep RTH altitude lower than the bridge itself in case this happens?

 

[dirkclod]

I believe hover would be best . The ones I go under I have it in LOS so I just go for it but that's me .

 

[Pathogen]

Generally speaking, the safety features like RTH and obstacle avoidance should be considered just as dangerous turned on as they are turned off, depending on pilot skill and type of activity. Flying beneath structures is particularly risky because GPS lock can fail. Being in ATTI mode with all other safety features disabled may be appropriate. Forcing ATTI mode requires directly editing parameters, and may be something an operator should consider learning before attempting dangerous flight operations.

 

[rfc]

. Forcing ATTI mode requires directly editing parameters, and may be something an operator should consider learning before attempting dangerous flight operations.

I wish DJI provided a way to put the Mavic into ATTI mode, as with the Phantoms, so one could practice flying with it enabled.

 

[Pathogen]

I wish DJI provided a way to put the Mavic into ATTI mode, as with the Phantoms, so one could practice flying with it enabled.

They did, but it seems the pinheads in the policy dept didn't call for the option to be built into the GO app. You can control the modes of the 'sport' switch using a parameter change using the Assistant software running in developer mode. More info can be found here: howto:parameterhacks [dji.retroroms.info]

 

[charliesRig]

Turn off your sensor while fling under bridge short bridge Usualy not issue
Long dark bridges...NO BEUNO

 

[rfc]

They did; More info can be howto:parameterhacks [dji.retroroms.info]

Thank you. Great info.

 

[black_magic100]

Turn off your sensor while fling under bridge short bridge Usualy not issue
Long dark bridges...NO BEUNO

But it doesn't matter if you have your sensors on or not. If you lose connection you are ******

 

[charliesRig]

If there is "water" under that bridge and your flying with in 30 ft of said water
With DPS on you better hope your Mavic shows you love and doesn't go rouge freak out end in the drink.

I never had that problem but a read others post and think about my chances of a safe landing before I do a bridge fly/ under and always turn my sesors off before

 

[JoostGT3]

Will the RTH function kick in and the drone just fly up and smack the bottom of the bridge since it doesn't have any sensors on the top? Is it a good idea to keep RTH altitude lower than the bridge itself in case this happens?

Haha I had the same question when I was planning a flight under a bridge over a river.

What I did is to set the RTH to "Hover" rather than "Rertun to Home", for exactly the same reasons:
In the area where I was filming, I was able to get quite close to the location of the bridge, so I figured if the connection would get lost, I would make my way to the bridge, hope for re-connection and fly the Mav out of there, rather than have it ascend and crash into the underside of the bridge, then falling into the river...

 

[black_magic100]

Haha I had the same question when I was planning a flight under a bridge over a river.

What I did is to set the RTH to "Hover" rather than "Rertun to Home", for exactly the same reasons:
In the area where I was filming, I was able to get quite close to the location of the bridge, so I figured if the connection would get lost, I would make my way to the bridge, hope for re-connection and fly the Mav out of there, rather than have it ascend and crash into the underside of the bridge, then falling into the river...

Oh ****. This was the answer I was looking for lol. Didn't even realize you could do that. Just for curiosity's sake... What if you weren't close to the bridge? Would it hover until the battery died or is their another setting where it will only hover and then RTH once the battery reaches a certain %?

 

[JoostGT3]

Oh ****. This was the answer I was looking for lol. Didn't even realize you could do that. Just for curiosity's sake... What if you weren't close to the bridge? Would it hover until the battery died or is their another setting where it will only hover and then RTH once the battery reaches a certain %?

Hmm, I would have to check whether you can separately set a "loss of connection RTH" setting and a "battery critically low RTH" setting. I think you can't. I think you can only set a "Smart RTH" setting, which will be triggered both by loss of connection and battery critically low, but not sure.

Also, I don't know if the behavior will be different between an RTH triggered by the user pushing the button or the smart RTH... Maybe one of the other users can chime in here?

 

[GlenT]

If setting the RTH to hover isn't a go for you, then set the RTH altitude somewhere above ground level but below bridge height. There are many options with the autonomous flight modes on the Mavic.
Have a read through this page from DJI for more RTH info, as one of the modes behaves differently when the Mavic is less than 20 meters away from you for example.
How to use DJI’s Return to Home (RTH) Safely