From the manual, RTH will detect the obstacle and go up 5 meters to over it.
Today I flew too far away and lost signal so Mavic pro went to RTH mode without vision.
When I came back home and checked the video, it is very scary - it just missed a high buiding at the right side which is higher than the maximum RTH altitude - I set to 80 meters.

What will happen if Mavic pro in RTH mode detected a high building but it is taller than 120m?
Will it hit the building? Or stay still as don't know what to do? Then too low battery will force RTH again, then land directly or hit the building? Or exceed the 120m limit?
I guess Mavic Pro doesn't know move left/right to avoid obstacle, right?

Anyone knows?

Thanks!


https://www.skypixel.com/videos/31de756f-2c7c-4f48-acf2-8be31bc58bec?utm_source=url&utm_medium=copied&utm_campaign=share

One thing to bear in mind is that the 120m is relative to ground based objects - so that could be 120m above buildings that end up along the RTH route. But presumably what (according the line 3.) the MPro does not do is, after flying over an object, then descend back to 120m relative to the 'new' distance to ground.

This is what makes me think the MP is capable of APAS...

I do not know for sure but offer my best guess. I think that the aircraft will ascend to whatever the max altitude you have set. if the obsticle is higher than 120m then i think the drone will hover in place until the battery gets to critical and then it will execute a landing going straight down - if there are obsticles on the way down i believe it will and on them either resulting in a lucky safe landing or an unlucky crash.

Bekaru Tree Posted at 2018-2-22 05:45
I do not know for sure but offer my best guess. I think that the aircraft will ascend to whatever the max altitude you have set. if the obsticle is higher than 120m then i think the drone will hover in place until the battery gets to critical and then it will execute a landing going straight down - if there are obsticles on the way down i believe it will and on them either resulting in a lucky safe landing or an unlucky crash.

Thanks Bekaru!
You are so smart - that's exactly the same as official answer I heard from DJI - best chance to protect the drone.
In future release, if DJI can add the AIR "turn left/right" to avoid obstacle to Pro, that will be smarter.

flybirdpro Posted at 2018-2-22 12:48
Thanks Bekaru!
You are so smart - that's exactly the same as official answer I heard from DJI - best chance to protect the drone.
In future release, if DJI can add the AIR "turn left/right" to avoid obstacle to Pro, that will be smarter.

thats good to know. and i must say that you too are smart for being able to get an official answer from dji - i do not see it posted in your thread, how did they reply to you.
I cant get them to answer anything:-(
Anyway i guess it follows then that if you suspect your drone might encounter a high obsticle on return, you could reset your altitude to higher than 120m.
so for example if you are in a valley and you fly over a hill that is say 110m high with some 30m high trees on the ridge and you are concerned the rth might not make it over the trees - you could reset your height and increase the odds that safe rth will be affected.

flybirdpro Posted at 2018-2-22 12:48
Thanks Bekaru!
You are so smart - that's exactly the same as official answer I heard from DJI - best chance to protect the drone.
In future release, if DJI can add the AIR "turn left/right" to avoid obstacle to Pro, that will be smarter.

Best way is to plan out your flights so you don't snooker yourself behind a hill/structure.

Aardvark Posted at 2018-2-22 15:11
Best way is to plan out your flights so you don't snooker yourself behind a hill/structure.

Thanks, that's true, nothing is better than a good planning and use normal features only.

Interesting thread - thanks for sharing.

You probably broke most of CASA's regulations to make this video so might be a good idea to delete it before they notice it.

* hex *

Hexacopter Posted at 2018-2-23 02:04
You probably broke most of CASA's regulations to make this video so might be a good idea to delete it before they notice it.

* hex *

Drone police always vigilant....

Lol. I have a licence RePL for Australia so each time some d**khead breaks the rules then CASA puts the screws on all other operators.

If somebody is so dumb to ask the OP's question then the safety word is not getting through.  

Any moron can purchase a drone but it takes a bit of intelligence to operate one, something that is sometimes lacking in these threads.

* hex *

There are a lot places to fly legally . The RTH is not controlled by the pilot.

I apology that I fall to moron's level when I self-defence against a moron.

flybirdpro Posted at 2018-2-23 13:24
There are a lot places to fly legally . The RTH is not controlled by the pilot.
Most of the people are nice to share, but some m*** f*** just be rude.
If someone is not try to help, please shut up, or at least don't be rude. Otherwise go and f*** yourself.

i totally agree.
Sarcasm and smart ass know it all remarks are not welcome here.

This forum provides a platform for people to learn from other pilots by posting questions videos and potential case scenarios.
When people are learning there are no stupid questions.

if you already know it all and do not wish to explain nicely then do not say anything.
Does not mean you will not have strong opinions but voice them maturely if you must say something.

if you are just commenting for the 2 points you will get, you only need to post 10 characters.
to whoever wants to just be effing rude - go find another forum.

What surprises me most in this partly very academic and partly less academic thread is one very gentle question that has not been asked yet ;-): If you fly your AC behind an obstacle higher than 120 meters and then wonder why it doesn't come back when connection is lost, what should such pilot action be qualified in terms of common sense?

Bekaru Tree Posted at 2018-2-22 05:45
I do not know for sure but offer my best guess. I think that the aircraft will ascend to whatever the max altitude you have set. if the obsticle is higher than 120m then i think the drone will hover in place until the battery gets to critical and then it will execute a landing going straight down - if there are obsticles on the way down i believe it will and on them either resulting in a lucky safe landing or an unlucky crash.

Manusl says it will climb over an obstacle and RTH at that altitude. Gotta remember as well that a sudden gust of wind from the side during an autonomous RTH could blow you off course into an obstacle. As said Pre-flight planning prevails.

QuadKid Posted at 2018-2-23 14:39
Manusl says it will climb over an obstacle and RTH at that altitude. Gotta remember as well that a sudden gust of wind from the side during an autonomous RTH could blow you off course into an obstacle. As said Pre-flight planning prevails.

preflight planning is 'best practice' and certainly reduces risk tremendously but not entirely because unforeseen things happen all to frequently.
Therefore discussing this question i consider to be well valid to helping new users understand certain dynamics so that they can either understand why to avoid them or what to do if they get caught up in an unforeseen situation.
Here is my real life scenario; i was flying from a valley up to the top of a hill about 110m height. it was a bright day and during the time i was struggling to see my devise screen and moving around trying to get the glare off it, i lost track of my drone and then i lost connection.
i pressed RTH and looked to see if i could spot my drone comming back. At this point i realised that i could not say where along the ridge my drone was and at a certain point there was a line of +/- 30 m high trees.
Fearing the possibility that it might encounter the trees on the way home i canceled the rth - reset my max alt and pressed RTH again - shortly after my device connected again and i flew home manually.

Bekaru Tree Posted at 2018-2-23 15:07
preflight planning is 'best practice' and certainly reduces risk tremendously but not entirely because unforeseen things happen all to frequently.
Therefore discussing this question i consider to be well valid to helping new users understand certain dynamics so that they can either understand why to avoid them or what to do if they get caught up in an unforeseen situation.
Here is my real life scenario; i was flying from a valley up to the top of a hill about 110m height. it was a bright day and during the time i was struggling to see my devise screen and moving around trying to get the glare off it, i lost track of my drone and then i lost connection.

Nothing more heart pounding than not knowing where your drone is (well maybe one thing;) ). I fly along the beach here in Daytona a lot, out flying one day around 80' AGL parallel to the beach when near the line of high rises along the shore. Probably 60-70' off the buildings when a sudden gust created a vortex between the building and just sucked my MP between the buildings loosing signal, I had reset the RTH altitude set to 300' AGL because of the buildings, good thing I did, when I lost the signal the MP went into a climb and ended up across the street above the roof of a supermarket before it regained signal and started coming home at 300' AGL.


A thorough Pre-flight is required before every flight as every flight is different, I normaly have the RTH altitude set at 48 meters just to avoid the trees when I fly locally. Below is a rough map if the instance.

flybirdpro Posted at 2018-2-23 13:24
There are a lot places to fly legally . The RTH is not controlled by the pilot.
Most of the people are nice to share, but some m*** f*** just be rude.
If someone is not try to help, please shut up, or at least don't be rude. Otherwise go and f*** yourself.

So, you're not helping AND you're being rude, meaning you just told yourself to go F yourself.

The irony.

Bekaru Tree Posted at 2018-2-23 14:23
i totally agree.
Sarcasm and smart ass know it all remarks are not welcome here.

Thanks mate! You are always helpful, share your experiences with others, so nice.
We learn from each other, especially other's mistakes - to avoid it happen again.
I asked this question and you said you don't know the answer because we are honest, someone said they know the answer just because they don't know what they are talking about.
There is no best practice or common sense here.
Like your mom asked you to turn left, your dad ask asked you to turn right, what will you do?
You can stay still, you can turn left/right, you can do other direction.
What is the best practice or common sense here?
It is just a decision, this decision was not made by any of us, or any government, just a programmer sit in DJI. How can others know their logic if it is not clearly documented?

Hexacopter Posted at 2018-2-23 02:50
Lol. I have a licence RePL for Australia so each time some d**khead breaks the rules then CASA puts the screws on all other operators.

If somebody is so dumb to ask the OP's question then the safety word is not getting through.  

Hi mate, I don't know why you behave in this way. You can criticize but don't attach people.
Apparently the education to teach you be a gentleman failed.
I can teach you again for free: think before you make an action, what will be consequence?

I draw this graph for you, hope you can learn how to talk to people.

BTW, after you got your license, did you ever break the rules?
If yes, please take all your dirty words to yourself.

Cheers,

djiuser_iGJqCoTNTQSa Posted at 2018-2-23 16:47
So, you're not helping AND you're being rude, meaning you just told yourself to go F yourself.

The irony.

I helped to raise question (it is valuable who understand it), I am doing self-defense.

What's your point here?
The irony of irony, right? So please take your words to yourself.

Don't get too antsy, you broke a few rules so I tend to get p*ssed off when people post photos that break the current laws here in Oz. Like the basic 30m separation rule.

I gave you a a nice and blunt unofficial warning.

For your education here is a copy CASA Rules (Australia) of the current rules.
You broke a few of them. I commented because when somebody breaks the rules the media howl and the laws get tighter and my RPA insurance skyrockets.

Putting your violations online is just evidence.

Feel free to come and discuss them at [url=Contacts  CASA (local call cost) 131 757 Sydney  Level 2 Centennial Plaza (Tower A), 260 Elizabeth Street, Sydney Fax: 02 8651 3072 Email: sydneyregion@casa.gov.au]CASA NSW[/url].

* hex *  

Hexacopter Posted at 2018-2-24 02:33
Don't get too antsy, you broke a few rules so I tend to get p*ssed off when people post photos that break the current laws here in Oz. Like the basic 30m separation rule.

I gave you a a nice and blunt unofficial warning.

All your criticize is accepted, I didn't argue with you. Can you tell how many rules I break from the video? I showed you the map.

Take all your dirty words to yourself, it just showed your education background, whatever your occupation or your certificate.

You didn't answer the question yet: after you got your certificate, did you ever break any of them?

In the forum, plenty of discussion, I will check Can I fly here before take off, but definitely sometimes it will be too small to see. Can you admit you never fly your drone out of view? So save your time.

You are not welcomed here. You can post a new topic to say what ever you want to say, how many dirty word you like, but please don't be rude in other people's post. This is basic manner.

Thanks!

Why have you set max altitude to 120 mtr? Mavic goes 500. Leave it at 500 and obtain the rules of your country but in case of a rth you don't have to worry about that. Before flight check highest building and set your rth height.

Jos A Posted at 2018-2-24 03:01
Why have you set max altitude to 120 mtr? Mavic goes 500. Leave it at 500 and obtain the rules of your country but in case of a rth you don't have to worry about that. Before flight check highest building and set your rth height.

In Australia, 120m is the max.

Ah but there's the thing 120M relative AGL - 'relative' can change as the ground under the drone including attached objects (buildings etc) changes. So it would seem prudent to set the max height up to a few metres about the highest likely object you will be flying in the vicinity of - so the RTH altitude will always be a bit higher than any intervening objects. Besides once the drone is on its way back to the Home point you can and probably should take back control and bring it back down to the correct relative AGL height (no more than 120m).