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Flying under bridges...eek!


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What about if you use Litchi waypoint to fly under? Is this any safer?

I do not recommend using way point missions unless you are really careful. The mission height is based on the height you initially take off from. So if you charge where you take off from and use the mission you could hit the bridge. Granted if the Mavic air (or any drone) sees the charge as minor you may not hit the bridge. But this is a real possibility. Also you could run into issue with wind making enough of a change to where the position is calculated that you could also strike the bridge. Not to mention if you have a curved path, that increases the chance of a strike too.

Overall, it can be done, but you have to plan for all the things that could change like the examples I provided. But half the fun is learning these things I guess, so long as the biggest risk is the props and a dent or scratch feel free to experiment a bit!
 
What if you switch the RTH to Hover just before you pass under the bridge so if you lose the signal instead of the drone climbing up in a certain altitude it will just stop & hover until you get closer to the aircraft & retrieve back the signal. Some shots just way look better under the bridge.[emoji1]

This sounds logical, but I can see where flying under a bridge is not enough to disturb the compass or GPS signal enough for a fault or collision to result. But sitting under the bridge for enough time could result in the GPS signal echo and a drift in the position and collision with the structure.

[I should note that GPS satellites are not stationary, they make a revolution around the planet once about every 12 hours, which means that in some positions under that bridge you can have a blocked view, loose line of sight to a satellite it was using to calculate its position, or a new one become visible. All these things effected how the craft may perceive it location under a bridge that has a blocked view to the sky above]

Flying through for a couple of seconds general is fine, but that hover on lost signal may bring you down depending on how long it takes you to reconnect to the craft.

My advise is if your going to fly through a structure like that, its best to be much closer and not risk that signal connection.
 
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How does she handle with those on? I was thinking of floats a s a safety measure for water flying, but those look like they would wreck handling and flight times.

You are thinking correctly.
While I fly my Air on floats sometimes it really does affect handling and flight times.

My float kit I made for my Mavic pro works really really well. Well it did after several revisions anyway. I have been flying on it over a year.
The Mavic Air just doesn't have the reserve power the pro does. Of course the floats are about half the size as the ones for the pro but they still bog it down more than I would like.
Unlike my Pro In 10mph plus winds the air can't hold its position with the floats on.
Also the floats cut the flight time on the air much more than the pro.

I will probably print some even lighter than what I have, and am considering Styrofoam floats. Playing around with modifications is what I do. The floats for me are mostly about flying my drones from my kayak when my wife and i paddle.
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So, for Air users specifically; before I try it, only to watch my pride and joy fall into a river, what has been people's real-life experience of flying under bridges in terms of potential or actual signal loss?

How close did you get to the bridge to control the drone, did you lose signal, even if just momentarily, and what sort of bridge was it? Large, small, metal, stone etc..?

Thanks!
A few months back some guy flew his MP under the Golden Gate Bridge--well he flew it half way or so and then he lost the signal and the bird dropped into the water never to be seen again. You see, bridges have this stuff called Steel and Concrete, both of which make signal reception (either from the RC or from GPS) very difficult. So if you want to fly under the bridge please be sure to video record the flight on your phone or pad so we can all watch your bird take a dunk.
 
So, for Air users specifically; before I try it, only to watch my pride and joy fall into a river, what has been people's real-life experience of flying under bridges in terms of potential or actual signal loss?

How close did you get to the bridge to control the drone, did you lose signal, even if just momentarily, and what sort of bridge was it? Large, small, metal, stone etc..?

Thanks!
I lost my first Mavic flying under Marine Park Bridge in Rockaway Beach New York.
I was pretty far away, actually the mavic was over a small berm from me, so the signal was already getting weak. First mistake. Second mistake was that it lost signal under the bridge, and went to return home, and I think it may have gone up and hit bridge from beneath.

You really have to look out for obstacles, and make sure return to home is configured so it won't
bash itself into bottom of bridge if it loses signal amongst all that metal.
 
Not long ago here in Australia I tried to fly under a railway bridge next to a road bridge with my new Mavic Air. The Air was flying fairly steadily under the railway bridge and then seemed to drop quickly towards the water. Luckily I was quick enough on the controls to back out from underneath the bridge and start to regain altitude at the same time. It happened very quickly and I was lucky to respond in time to save my new Air from impending disaster. Better luck than judgement I would say!!!!
Dont know whether it was a loss of satellite, VPS or altitude hold or something else. All I know is that I will think twice before I fly my expensive camera under another bridge again.
 
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No problems here. The Mavic Pro dipped a bit in altitude when flying through the covered bridge but i was able to recover it. You can see it on the video.

 
So, for Air users specifically; before I try it, only to watch my pride and joy fall into a river, what has been people's real-life experience of flying under bridges in terms of potential or actual signal loss?

How close did you get to the bridge to control the drone, did you lose signal, even if just momentarily, and what sort of bridge was it? Large, small, metal, stone etc..?

Thanks!
I’m new to this but have been experimenting with MVA. Maybe turn off GPS ? As you fly near/around or under structures you run the risk of loosing a gps satellite signal (or more), the Mavic looses its orientation and may try to “correct” its position, then you run the risk of “bye-bye Birdie” . Just my $ .02
 
I've flown under large bridges in urban and rural areas, as well as smaller bridges in rural areas, usually over the water. Had no issues flying 1800 ft away under a large I-90 bridge carrying 6 or 8 lanes. On the other hand, I lost the signal within LOS less than 200 feet flying under a small steel bridge over the river. You'll just have to try it. Make sure it is within LOS.
 
I read on one of the Facebook forums (DJI Mavic Air Owners Group) about a guy that flew under a rock bridge in Indonesia and watched it fall into the water..... Drone gone. I like these forums as I like to learn from other people's mistakes.
 
I have seen a few videos of crashes while going under bridges.
I think the common thing that happens is first you lose connection to the drone because it is blocked by the bridge. Compass and GPS errors insue. When the mavic cant see the remote anymore, it hovers for a bit, then RTH is initiated. If you are under a bridge when this happens the mavic attempts to climb to the RTH altitude and crashes into the bridge. The uneducated Mavic owner will say "it was out of control flying on its own"

For the following months you will have to argue with DJI about not replacing your drone for free.

I wouldnt risk it unless your OK with the potential loss of your investment.
If the bridge is big enough there would be no GPS so no effective RTH either. So what will it do when there are no signals from anything? I guess hover and drift in atti?
 
Have you thought about putting the .stl files out on a site like Thingiverse?

I have a few files I have put on thingiverse. I may put the Mavic air files there if I don't sell the float kits.

Mike
 
I've flown under quite a few with no issues. One from about a mile away. Plan on doing more.!!
 
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