Rapid descent, how?

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While it may be a matter of preference, experience or skill, backwards motion poses no different aerodynamic ‘threat’ to your flight.
Hi, not flying backwards whilst having the throttle shut off is not a concern about aerodynmaics, it's solely about tempting fate with an inadvertent CSC.

Andy there is a youtube video of a successful phantom mid air CSC stop and restart and I have wondered about it but it's a scary thought, I think it would be an absolute last resort.
I think the video is ....https://www.youtube.com/watch?v=P20jEzQ5eU0
the beginning seems a bit ......odd!


Re Terns
I seem to remember a BBC nature programme presenter getting dive bombed, maybe even David Attenborough


 
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Fly-Dawg that's looks more like a mosquito to me, midges = https://www.google.com/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&ved=2ahUKEwjhmI7m1KvjAhU3D2MBHVKLCicQjRx6BAgBEAU&url=https://www.youtube.com/watch?v=Ox8SwZCvugE&psig=AOvVaw2c2oMMi_VLpX5IdWJTNmCY&ust=1562893141001803
and yes I have seen it nearly that bad

Teccer I have quite often come down with the 'throttle' fully 'closed', and when this is purely vertical and nearby it is evident that the drone wobbles a bit, I assume because it is encountering turbulent air etc. However I have not encountered a motor stop problem and the longest throttle fully closed descent session would probably have been 30sec or more, I had been highish and was getting nervous about the time it was taking to come down. Given open space I will however try to avoid 'fast' purely vertical descents by adding a little sideways or forward travel but try to avoid backwards travel, no point in tempting fate.

glad to hear that you've done the fully back on L stick for up to 30 seconds, now I'll have no problem doing it next time I need to plus a bit of right stick forward,
as for NO17RWs comments that it's ok to use right stick back as well as the left, I won't be doing that because you /I might have a bit of center in as well, result, complete switch off and as you said, no point in tempting fate
 
Teccer, you can always be daft and do what I have just done.
Start the drone with the CSC then pick it up by one of the back legs near the top of that leg with your thumb low down on the arm. Then, holding tight, give it just enough throttle to feel its weight lessen. Then shut the throttle off and keep it off whilst waggling the drone about enough that you can feel the motors changing speed as the control system tries to keep it level. I am deaf so sound variations do not register. I think you will find the props will not stop until you hold the drone still.

KEEP YOUR THUMB/FINGERS AWAY FROM THE PROPS
 
CSC takes 4 channels to be fully deflected.
 
Taking "4 channels" to mean 4 distinct stick movements (fully down and then fully across ) x 2, agreed. But I'd still rather not tempt fate.
Ultimately, for vertical descents, I'd like to be able to forward-spiral down but my stick control isn't there yet.
If I recollect correctly did not DJI change the P4 stop motors CSC, possibly because of inadvertent mid air CSC's, to a simultaneous button press and single joystick movement via a firmware update? If I am correct I wonder if they could do the same for P3 pilots?
 
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Whatever works for you but it’s not fate.
Sounds more like misunderstandings.
 
One aims to please :)
It worked as a demonstration/experiment though. :) :) :)
 
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Don't try that with an African Bee Swarm.....although I have encountered black bird swarms.....Now that is scary stuff to fly in.

Sounds like a second person not reading the post correctly. The OP was not flying in the swarm of midges. He was surrounded by them while the drone was flying elsewhere.

My own thought was...if in doubt RTH. As mentioned, running for cover and letting the drone land itself seems preferable.
 
The OP was not flying in the swarm of midges. He was surrounded by them while the drone was flying elsewhere.
As was I as shown in Post#8. I was not flying in the swarm, just avoiding them while landing.
 
Just bring it overhead, point camera down & make sure it'll land clear, that Auto Land & set your controller down. Wait in the car until the Eagle Has Landed.....
 
Hi, not flying backwards whilst having the throttle shut off is not a concern about aerodynmaics, it's solely about tempting fate with an inadvertent CSC.

Andy there is a youtube video of a successful phantom mid air CSC stop and restart and I have wondered about it but it's a scary thought, I think it would be an absolute last resort.
I think the video is ....https://www.youtube.com/watch?v=P20jEzQ5eU0
the beginning seems a bit ......odd!


Re Terns
I seem to remember a BBC nature programme presenter getting dive bombed, maybe even David Attenborough

Has anyone tried to operate fly from in side car? That might work I might try and see if that works!
 
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in the case of the P3adv, "manual" translates to "A-mode" (mode switch in the middle position)?
Correct. "Manual" mode is ATTI. (aka...switch in the A position) for a P3. But also be aware that the aircraft can and will auto switch to that mode in the event of a GPS and/or Compass related issue.
 
It might be possible to engineer into a drone a mode of descent that consumes battery power at a minimal rate. The idea would be to let the props spin in the opposite direction (with a little resistance) during much of the descent. This would help to slow and stabilize the descent. The props could be restarted when the drone gets close to the ground.
 
Well......I finally tried a mid air CSC, terminal velocity 15 to 16m/s, and restart, interesting experience.
It raised two points I think might be worth drawing to people's attention.
1) The motors restart and settle to idle, I had presumed they'd 'spin up' to stop the descent but they didn't. That was a "oh sugar I am going to lose it" moment, once I realised what was happening and throttled up the descent stopped. The motors do however stop the drone's spin as soon as they restart.
2) The restart resets the home point, as it should, but I hadn't thought of that and as I had lost sight of the drone during its freefall I initiated an RTH. Another "oh sugar" moment as it asked if I wanted to land (over the sea). It would therefore be advisable to reset the home point yourself to the CONTROLLER's location after such a restart.
Looking at the video the drone showed no inclination to tumble but continued to spin through out the freefall.

Point 1) makes me wonder if, if such a manoeuvre is necessary, the safest thing to do would be to restart the motors as soon as the freefall started and let the drone fall with the motors at idle then throttle up once you were clear of the danger?
 
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Well......I finally tried a mid air CSC, terminal velocity 15 to 16m/s, and restart, interesting experience.
It raised two points I think might be worth drawing to people's attention.
1) The motors restart and settle to idle, I had presumed they'd 'spin up' to stop the descent but they didn't. That was a "oh sugar I am going to lose it" moment, once I realised what was happening and throttled up the descent stopped. The motors do however stop the drone's spin as soon as they restart.
2) The restart resets the home point, as it should, but I hadn't thought of that and as I had lost sight of the drone during its freefall I initiated an RTH. Another "oh sugar" moment as it asked if I wanted to land (over the sea). It would therefore be advisable to reset the home point yourself to the CONTROLLER's location after such a restart.
Looking at the video the drone showed no inclination to tumble but continued to spin through out the freefall.

Point 1) makes me wonder if, if such a manoeuvre is necessary, the safest thing to do would be to restart the motors as soon as the freefall started and let the drone fall with the motors at idle then throttle up once you were clear of the danger?


Surely you're going to share that video :)
 
I think some are missing the OP problem. It was not the AC that was under threat but himself being eaten alive by midges and he wanted to get the AC down ASAP so that he could get away from the swarm - I think???
AS for "Blackbirds" swarming, in the UK Blackbirds are solitary creatures, they don't swarm (flock) The only bird here that flocks, called a murmuration, are Starlings, usually in the late evening coming in to roost.
murmuration.jpg
 

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