CSC motor stop during flight?

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So I'm rereading the full manual for my P3P and I got to the section of stopping the motors. We all know there's 2 methods, holding the throttle stick down after landing. Or using the CSC method (which also starts the motors). Oddly, the manual specifically states to NOT do a CSC motor stop during flight as it will stop the motors mid air. That can't be right!!! Is that actually possible (I doubt any one has tried lol)??? And would you be able to restart them during free fall? I can only think of one flight situation where this might actually be useful but I cant believe the app will actually allow a full motor stop midflight. Can anyone confirm this?
 
So I'm rereading the full manual for my P3P and I got to the section of stopping the motors. We all know there's 2 methods, holding the throttle stick down after landing. Or using the CSC method (which also starts the motors). Oddly, the manual specifically states to NOT do a CSC motor stop during flight as it will stop the motors mid air. That can't be right!!! Is that actually possible (I doubt any one has tried lol)??? And would you be able to restart them during free fall? I can only think of one flight situation where this might actually be useful but I cant believe the app will actually allow a full motor stop midflight. Can anyone confirm this?
Yes, a CSC will stop the motors in flight. You'd be amazed with how many very long and sometimes argumentative threads there are on this topic.
 
Oddly, the manual specifically states to NOT do a CSC motor stop during flight as it will stop the motors mid air.
That is correct, however there was a change in firmware to lengthen the CSC time for shutdown if I am not mistaken.
 
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Thats crazy!!! Altho in a situation where the winds are so strong that GPS mode wont allow a descent as it's already using full power trying just to maintain position, you have only 2 options, a controlled drifting descent with the wind in Atti mode and hope the AC gets below the wind and has enough battery to get home, OR, do CSC motor stop and let it free fall. Next question is, if you restart the motors during freefall, will the AC reorientate itself and come under control again?
 
Next question is, if you restart the motors during freefall, will the AC reorientate itself and come under control again?
Not sure that you can re-start. I fly with very old firmware, and at least in my case I know for a fact that after landing and stopping the motors, they will not re-start without an aircraft re-boot. So that tells me that the same applies for a mid-air CSC. Again, at least in my case. Newer firmware may be different.
 
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Im using the latest FW and i can land, stop the motors, restart them and take off again without a restart so I'd assume I could do the same during free fall. Question is, what happens if the motors start and the AC has tumbled and is upside down? Would the Imu know this and correct?
 
I fully realize this entire conversation is moot as no one in their right mind is gonna test what would happen under this scenario but nonetheless, I do wonder if the P3 could actually recover from such a series of events.
 
Im using the latest FW and i can land, stop the motors, restart them and take off again without a restart so I'd assume I could do the same during free fall. Question is, what happens if the motors start and the AC has tumbled and is upside down? Would the Imu know this and correct?
I can also routinely restart the motors after stopping them on the ground without requiring a full reboot.

As for surviving a free fall by restarting, that is another one asked so many times that I added it to my list of tips a couple of years ago. That was at a time when people were regularly losing their P3's with accidental CSC commands in the air. This was the reason for so many arguments as some insisted that it was impossible to accidentally do a CSC in flight while others were actually doing it accidentally a few times per month. After a while, assuming an accidental CSC when a crash was reported became a routine diagnosis and people started selling 3D printed devices to attach to the sticks which prevented a CSC. Mike Singer even printed and generously gave away many of these to members here.

DJI changed the command as noted earlier to add a delay when before it was instant. I think with the P4 they even changed the command in 2016 to require a button and a stick rather than just two sticks.

I seem to recall an effort in maybe 2015 to group fund a P3 so that someone could test if a P3 could recover from a CSC since they could do it in the simulator. Others have said that they've seen videos of success with a P3 similar to the recent videos showing a Mavic recovering.

What I always tell people when they ask is that a P3 won't recover unless by some unusual and rare accidental recovery, but if someone wants to try it to please capture a video of the attempt so we can see the crash. :)
 
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I fully realize this entire conversation is moot as no one in their right mind is gonna test what would happen under this scenario

People do claim to use that, but only for record breaking and showing off.
You have to modify the firmware to allow starting motors when the drone is at angle, otherwise you won't be able to restart.

@Oso summarized that well - there is clear video evidence for doing this only for Mavic.
 
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People do claim to use that, but only for record breaking and showing off.
You have to modify the firmware to allow starting motors when the drone is at angle, otherwise you won't be able to restart.

@Oso summarized that well - there is clear video evidence for doing this only for Mavic.
Very interesting!
 
Ok youve all got me curious. Im gonna hookup my system. Power on the AC while its level. Point it face down and try and do a motor start (with no props obvs) and see what happens. Will report back soon.
 
@quaddamage Yes you are absolutely correct as shown here:
Screenshot_20181104-104356_DJI GO.jpg
 
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Thats crazy!!! Altho in a situation where the winds are so strong that GPS mode wont allow a descent as it's already using full power trying just to maintain position, you have only 2 options, a controlled drifting descent with the wind in Atti mode and hope the AC gets below the wind and has enough battery to get home, OR, do CSC motor stop and let it free fall. Next question is, if you restart the motors during freefall, will the AC reorientate itself and come under control again?
I can't imagine weather that would your drone would not be able to descend unless you are flying inside a tornado and then stopping the motors won't get you down.
A strong wind might prevent the drone from going forward but it would never prevent you descending.
 
I can't imagine weather that would your drone would not be able to descend
Thunderstorm thermal updrafts would prevent decent. Other than what you mentioned, that is the only other way that I can think of. And at times these can occur far before the storm, which in some cases we do fly in for distant lightning filming.
 
I fully realize this entire conversation is moot as no one in their right mind is gonna test what would happen under this scenario but nonetheless, I do wonder if the P3 could actually recover from such a series of events.
This has been done with a Mavic Pro.
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I see no reason why it couldn't work with a Phantom. But I sure as hell am not going to try it!

And the reason DJI incorporated this feature is to be able to shut off the motors in the extreme circumstance where the AC is likely going to collide with someone. I don't think most operators could react that quickly, but it is a CYA effort on the part of DJI.
 
I can't imagine weather that would your drone would not be able to descend unless you are flying inside a tornado and then stopping the motors won't get you down.
A strong wind might prevent the drone from going forward but it would never prevent you descending.
@Meta4 here is a link to a video which, in my opinion, shows exactly the situation where trying to descend would do nothing. If "PGPS" is active and the AC is fighting to hold position with full thrust, and you try to slow the props down to descend and the AC starts drifting, GPS will take over and not allow the descend. You would have to enter Atti mode and do a descent while drifting away to lower the AC. Watch and see what you think.
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[/QUOTE]
 
This has been done with a Mavic Pro.
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I see no reason why it couldn't work with a Phantom. But I sure as hell am not going to try it!

And the reason DJI incorporated this feature is to be able to shut off the motors in the extreme circumstance where the AC is likely going to collide with someone. I don't think most operators could react that quickly, but it is a CYA effort on the part of DJI.
Wow so it can be done!!!!
 
@Meta4 here is a link to a video which, in my opinion, shows exactly the situation where trying to descend would do nothing. If "PGPS" is active and the AC is fighting to hold position with full thrust, and you try to slow the props down to descend and the AC starts drifting, GPS will take over and not allow the descend. You would have to enter Atti mode and do a descent while drifting away to lower the AC. Watch and see what you think.
I'm not certain that a modern Phantom would behave the same way (I'm not going to be testing to find out if it is).
The video pilot said his flight controller was using all power to maintain position against a headwind but if you are telling it to go down and forward, it shouldn't be trying to maintain position at all.
I've seen flight records where people flew too high in the mountains and got into a situation where the drone was being flown back but going backwards.
That one responded properly to the left stick being pulled back.

That's flying in conditions that are far from normal and I would think it fits into the same category as flying in thunderstorm updrafts or tornados.
Not something anyone is going to do in normal flight and if you did, you are going to have more problems than descending.
 
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