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Mavic Air 2s crashed while trying to launch off balcony

Yeah ... that's good, but a yaw error isn't created at "take-off".

When you power on your drone the IMU know nothing about the cardinal directions & how the craft is pointing in relation to those ... and it's the IMU that's primarily used airborne, not the compass.

A yaw error is created in the moment when you power on your craft ... in that moment the compass will tell the IMU the cardinal directions. If the compass is deflected in that moment the IMU will be wrongly initialized & cause it to believe that the craft is pointing in another direction than the correct one. The compass will quickly be corrected once leaving the disturbed area ... but the IMU will remain wrong.

So if you accidentally power on your craft too near magnetic interference ... & then put it down for take off far away from magnetic objects the damage is already done.

Then regarding landings ... or general flying near or in a magnetic disturbed area. It's correct that the compass will slooowly feed in corrections to the IMU over time, so leaving the craft in magnetic disturbance will eventually cause problems but it will take time, both due to that you rarely are that near magnetic objects during flight (like a drone foot/leg distance from it) & due to that the compass isn't the only one that feed in corrections to the IMU, both the gyro & the VIO sensor (a turning measurement created from the bottom VPS sensor) does that also. I wouldn't be particular afraid of magnetic disturbance induced problems neither during flight or during normal landings.

Power on your craft in your out stretched hand (no watches, bracelets or rings near that hand) ... then your craft is around 1,5m above ground & away from your body/clothes with perhaps zippers & buckles. Once the live view have been activated in the app the IMU have been properly initialized. After that you can place it on ground for take off. Before getting airborne you ALWAYS check the drone icon on the map in the app & confirm that it's pointing equal to the map objects (roads, houses etc.) as the craft does in reality.

Do this & you have massively minimized the risk for a yaw error ...
Superb answer, stunning! so you say you should be almost sure you avoid yaw error this way, but how to be fully sure? If the craft wont show any compass error or any error, can It still be having one compass error? thanks a lot.
 
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Superb answer, stunning! so you say you should be almost sure you avoid yaw error this way, but how to be fully sure? If the craft wont show any compass error or any error, can It still be having one compass error? thanks a lot.
In alot of cases no compass error have been thrown even though the compass was deflected during the power on (when the IMU becomes initializes) ... so no error isn't a guarantee that you've avoided a wrongly initialized IMU at all.

You ALWAYS do according to below before getting airborne ... if the drone icon point wrongly you know that you have a yaw error & you need then POWER DOWN the drone, move away to another launch place far away from the first & try again.

"Before getting airborne you ALWAYS check the drone icon on the map in the app & confirm that it's pointing equal to the map objects (roads, houses etc.) as the craft does in reality".
 
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In alot of cases no compass error have been thrown even though the compass was deflected during the power on (when the IMU becomes initializes) ... so no error isn't a guarantee that you've avoided a wrongly initialized IMU at all.

You ALWAYS do according to below before getting airborne ... if the drone icon point wrongly you know that you have a yaw error & you need then POWER DOWN the drone, move away to another launch place far away from the first & try again.

"Before getting airborne you ALWAYS check the drone icon on the map in the app & confirm that it's pointing equal to the map objects (roads, houses etc.) as the craft does in reality".
A real privilege to receive a reply from you sir, big respect from Panamá! I want you to be the supervisor of my first mavic mini third floor balcony flight. Ive flown a couple of years ago with a Spark and in one ocassion almost lost it but was able to get it back, nowadays i am studying much more this special flight scenario as the normal open field are really too easy to accomplish. and feel more confident with your help.
1. Mavic Mini in the floor of the balcony shows no problems at all with any errors or callibrations asked to be performed. Is it they dont use rebar for this building? LOL.
2. In the floor it wont get more than six satellites so the drone map point shows in black, but if I place it atop the side wall it gets the Home Point Recorded Message and I am able to verifiy the heading is correct, using Compass apps and moving the drone the arrow is where it needs to be pointing. Good symptom... as you instructed us.
3. Once the Home Point is set its strange that a blue straight line comes from the back of the building to where the H appears as if it moved.... and also that home point is a house beside my building.... but that dont bothers me as RTH will be cancelled if needed and fly manually.
4. No winds, open blue sky, good to go on UAV Forecast, my question is AM I READY FOR TAKEOFF? and a big thanks and take care bro.
 

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1. Mavic Mini in the floor of the balcony shows no problems at all with any errors or callibrations asked to be performed. Is it they dont use rebar for this building? LOL.
You mean that you up til now have been lucky & managed to avoid placing your drone on top or close enough to a rebar in the concrete ...
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2. In the floor it wont get more than six satellites ..., but if I place it atop the side wall it gets the Home Point Recorded Message...
3. Once the Home Point is set its strange that a blue straight line comes from the back of the building to where the H appears as if it moved.... and also that home point is a house beside my building.... but that dont bothers me as RTH will be cancelled if needed and fly manually.
If you for a sec try to recall what the lady voice says when the HP have been recorded ... "-please check it on the map". That means that you should make sure it's recorded in the correct spot.

This will not give you any problems if you're able to maneuver the drone back manually ... but what if you lose the connection & the failsafe RTH kicks in & you can't regain the connection before it lands ... in the wrong spot?

...my question is AM I READY FOR TAKEOFF?
Taking off & land drones from balcony's is really a risky business, especially if you don't have a deep understanding about how these drones work & where the risks are and what the consequences could be if not "bothering" about crucial thing's.

My advice is that you try to find an open launch spot on ground level, free of everything that could cause magnetic interference & make sure that the HP is recorded in the right place.
 
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Launching through a window or off a balcony, you also have to be very aware of the take off procedure for manual or hand launching.
The drone will rise X distance under auto take off, so if using that watch it won't hit the balcony overhang if hand launching.

Practice on the ground outside to try and replicate those scenarios and watch how the drone behaves.
It might be with reduced sats it may be less stable until well outside in clear skies too, really fraught with danger as a new pilot.
First flights, pilot or drone, I would recommend only doing it outside safely.
As you become competent in both flying and understanding all the behaviours of your drone, start flying through things, under things, big gaps at first of course.

RTH functions, and obstacle avoidance are 2 other things you must be aware of the consequences when taking off and landing.
 
Launching through a window or off a balcony, you also have to be very aware of the take off procedure for manual or hand launching.
The drone will rise X distance under auto take off, so if using that watch it won't hit the balcony overhang if hand launching.

Practice on the ground outside to try and replicate those scenarios and watch how the drone behaves.
It might be with reduced sats it may be less stable until well outside in clear skies too, really fraught with danger as a new pilot.
First flights, pilot or drone, I would recommend only doing it outside safely.
As you become competent in both flying and understanding all the behaviours of your drone, start flying through things, under things, big gaps at first of course.

RTH functions, and obstacle avoidance are 2 other things you must be aware of the consequences when taking off and landing.
Thanks a lot for your comments, but they are basic, for new under 500 hundred flights hour pilots, still they are really true! and thanks again. Now completed 24 full time flights from balcony, 6 batteries per day, no problems. No rocket science, technology deserves its respect.
 
You mean that you up til now have been lucky & managed to avoid placing your drone on top or close enough to a rebar in the concrete ...
View attachment 134657


If you for a sec try to recall what the lady voice says when the HP have been recorded ... "-please check it on the map". That means that you should make sure it's recorded in the correct spot.

This will not give you any problems if you're able to maneuver the drone back manually ... but what if you lose the connection & the failsafe RTH kicks in & you can't regain the connection before it lands ... in the wrong spot?


Taking off & land drones from balcony's is really a risky business, especially if you don't have a deep understanding about how these drones work & where the risks are and what the consequences could be if not "bothering" about crucial thing's.

My advice is that you try to find an open launch spot on ground level, free of everything that could cause magnetic interference & make sure that the HP is recorded in the right place.
Many thanks as always for your replies! probably some unnecesary roughness dou, but you are kind of right. I will only ask if according to your knowledge theres no one ready for takeoff from a balcony? Many years on this, many many flight hours, no problems yet.... Being at ground level dont means theres no rebar or EMI there neither. Off course on a balcony the amount of satellites wont comply with the density of them and the needed separation of them, but it works. You said that even no compass error wont mean theres a clean compass at takeoff and we must check the arrow and orientation, etc. Even then you still wont have for sure a clean compass initialization according to your experience?
 
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