Stopping motors in the air

[FlyHighUSA]

are you serious????? you think I hadn't thought of that!!!! The same failure can be reproduced with a 100 percent charged battery time after time. I sent my data logs to DJI and they verified what I was saying. The battery only matters because it caused me to put a lot more throw than normally is needed for normal flying. The battery is circumstantial, I have been flying for over 30 years and I am a pilot so I have a little experience in the matter. If it were the battery then I could not duplicate the same issue with a 100 percent charged battery over 3 different drones. Thanks for the inservice

 

[Kilrah]

Well, should you have given that info straight away it would have been more clear. The way you worded it didn't suggest you considered it.

But...

If it were the battery then I could not duplicate the same issue with a 100 percent charged battery over 3 different drones.

Again, bad wording - what do you mean there? Are you talking of using the same battery that caused the issue, but charged and on different machines? Or different batteries on the same machine?
This sounds like "I tried the same battery on 3 machines after fully charging it and also had the problem", which to me points again to that battery being faulty.
Try to be clear with what troubleshooting steps you took if you want input...

 

[FlyHighUSA]

Different batteries I would never put a battery back in a drone that was faulty, That would be stupid and I am not stupid! It's really just common sense. I was actually just letting everyone know there could be a potential issue. I'm not really looking for imput on this one as I have DJI looking at this for me. I don't think my wording is bad!

 

[lake_flyer]

Here we go again....

This discussion is useless. It's not going to change.
The CSC is ONLY to start the motors. And ONLY to kill them in flight in an emergency.
Don't use it to stop your engines after landing, just keep the throttle down until full stop. With a CSC the Inspire could tip over while already on the ground.

A CSC full stop is immediate, not 1.5 or 2 seconds later! As soon as you have the second stick in the inner corner it stops the engines immediately, there's no delay, so don't think you can correct yourself after a CSC. To restart the engines you need to let the sticks go back to neutral and perform the CSC again. Engines will start immediately but take 1 to 2 seconds to spool up to hover power. At terminal velocity that means it will drop at least 50m or 150ft before it starts to hover again. Due to the lack of drag of the Inspire airframe terminal velocity is reached within seconds.

There is no way that any pilot to pull both sticks down and inward for any kind of flight with a multirotor.

I would encourage everyone to try this out in the simulator. It helps to know and feel what it's like to do CSC mid air.

I would not want a switch for this. A switch can malfunction and switched for whatever reason. CSC is a very deliberate action for any trained pilot. In the hands of a child or a total noob anything can happen of course.
We will learn soon after christmas, I'm afraid.

 

[FlyHighUSA]

Well, should you have given that info straight away it would have been more clear. The way you worded it didn't suggest you considered it.

But...


Again, bad wording - what do you mean there? Are you talking of using the same battery that caused the issue, but charged and on different machines? Or different batteries on the same machine?
This sounds like "I tried the same battery on 3 machines after fully charging it and also had the problem", which to me points again to that battery being faulty.
Try to be clear with what troubleshooting steps you took if you want input...

Also,

Here we go again....

This discussion is useless. It's not going to change.
The CSC is ONLY to start the motors. And ONLY to kill them in flight in an emergency.
Don't use it to stop your engines after landing, just keep the throttle down until full stop. With a CSC the Inspire could tip over while already on the ground.

A CSC full stop is immediate, not 1.5 or 2 seconds later! As soon as you have the second stick in the inner corner it stops the engines immediately, there's no delay, so don't think you can correct yourself after a CSC. To restart the engines you need to let the sticks go back to neutral and perform the CSC again. Engines will start immediately but take 1 to 2 seconds to spool up to hover power. At terminal velocity that means it will drop at least 50m or 150ft before it starts to hover again. Due to the lack of drag of the Inspire airframe terminal velocity is reached within seconds.

There is no way that any pilot to pull both sticks down and inward for any kind of flight with a multirotor.

I would encourage everyone to try this out in the simulator. It helps to know and feel what it's like to do CSC mid air.

I would not want a switch for this. A switch can malfunction and switched for whatever reason. CSC is a very deliberate action for any trained pilot. In the hands of a child or a total noob anything can happen of course.
We will learn soon after christmas, I'm afraid.

you are absolutely correct in everything you just said. The CSC is a very deliberate act. I was referring to a malfunction that I was having with my bird. I have been flying for many years and this is my first experience with this. Mine is cutting off simply by lowering the throttle stick to a low position. Am I correct that this should not turn it off? I appreciate your input.

 

[lake_flyer]

Also,

you are absolutely correct in everything you just said. The CSC is a very deliberate act. I was referring to a malfunction that I was having with my bird. I have been flying for many years and this is my first experience with this. Mine is cutting off simply by lowering the throttle stick to a low position. Am I correct that this should not turn it off? I appreciate your input.

It should not cut off unless you totally have both sticks down and inwards. It should kick in as soon as the second stick has reached the end of travel (whatever stick is last).
If that's not the way it works in your case, it must be a calibration or transmitter fault. Have you tested it in the simulator (the sim uses your live stick calibration so you can check what would happen in a live situation)

 

[FlyHighUSA]

It should not cut off unless you totally have both sticks down and inwards. It should kick in as soon as the second stick has reached the end of travel (whatever stick is last).
If that's not the way it works in your case, it must be a calibration or transmitter fault. Have you tested it in the simulator (the sim uses your live stick calibration so you can check what would happen in a live situation)

Yes I have done the sim and it is the same result. I sent my data log to DJI and they are looking at them now. It's disarming by just lowering the throttle stick. I have done stick Cali etc... Same thing. I will wait to see what DJI says. I have another Inspire Pro coming Monday. I will see how it goes. Thanks for not being rude to me. I appreciate the advice

 

[Meta4]

Will it shut them off on full throttle down when it is in the air?

I know the csc will, but I am wondering because a full throttle down is how I stop the props once it is on the ground, and I am afraid to test this while descending. I usually descend at 3mph, but I notice when testing the RTH it was dropping much quicker

I was referring to a malfunction that I was having with my bird. I have been flying for many years and this is my first experience with this. Mine is cutting off simply by lowering the throttle stick to a low position. Am I correct that this should not turn it off? I appreciate your input.

I'm paranoid when it comes to long descents. I'll pulse the controls on the way down instead of holding down. Supposingly holding down on the controls while flying won't kill the motors. I believe the vps needs to see or sonically hear the ground to enable this feature. The simulator verifies this. But I'm not testing it myself. I'll just keep to my paranoid pulsing.

Left stick down should not kill your motors in flight - if it's happening, you have a serious malfunction.
It's amazing how many people believe that DJI design engineers could be smart enough to create the Inspire but have the normal descent procedure kill the motors in flight.

Left stick down is the normal descent procedure and you can descend at full speed with no need to pulse the controls.
Left stick down will kill the motors when the input from the barometer to the flight controller indicates that the Inspire has not descended for 3 seconds despite the throttle being in the full down position ie. the Inspire has landed.

 

[lake_flyer]

but I notice when testing the RTH it was dropping much quicker

Your right. RTH is not the ideal way to land. It comes down with landing arms down (less stability) at maximum descend speed of 4m/sec, and vertical. The classic recipe for VRS (google that if you don't know what it means, a ton of discussions on the web about that).
Always descend in a slope preferably with the nose in the wind.

Different discussion but worth to mention I think.

 

[FlyHighUSA]

Left stick down should not kill your motors in flight - if it's happening, you have a serious malfunction.
It's amazing how many people believe that DJI design engineers could be smart enough to create the Inspire but have the normal descent procedure kill the motors in flight.

Left stick down is the normal descent procedure and you can descend at full speed with no need to pulse the controls.
Left stick down will kill the motors when the input from the barometer to the flight controller indicates that the Inspire has not descended for 3 seconds despite the throttle being in the full down position ie. the Inspire has landed.

Left stick down should not kill your motors in flight - if it's happening, you have a serious malfunction.
It's amazing how many people believe that DJI design engineers could be smart enough to create the Inspire but have the normal descent procedure kill the motors in flight.

Left stick down is the normal descent procedure and you can descend at full speed with no need to pulse the controls.
Left stick down will kill the motors when the input from the barometer to the flight controller indicates that the Inspire has not descended for 3 seconds despite the throttle being in the full down position ie. the Inspire has landed.

Like you said it sounds like a faulty barometer.

 

[FlyHighUSA]

Like you said it sounds like a faulty barometer.

That would make sense.

 

[Meta4]

There is little point in shutting down the rotors in all but the very rarest of cases. If the rotors are still turning the drone is not in free-fall there is a degree of retardation to the descent and you always have the possibility to recover. If you crash and hit something with the rotors running they stop themselves WAY faster than the three seconds it takes for you to shut them down, they may spin quickly but they don't have enough power to have inertia and significantly damage anything

This is correct. The concept of using CSC in mid-flight to avoid catastrophe is fanciful and extremely unlikely to ever be used.
CSC is the emergency stop feature and is generally for use when the Inspire is on the ground or in a tree or some other situation where it is important to stop the spinning props quickly..

 

[lake_flyer]

Like you said it sounds like a faulty barometer.

clever thinking, you might be right.

 

[lake_flyer]

CSC is the emergency stop feature and is generally for use when the Inspire is on the ground or in a tree or some other situation where it is important to stop the spinning props quickly..

Totally right!
And when on the ground, IF you need to CSC, do it very quickly. If you do it with any hesitation it will respond to the stick input and go nuts in front of your feet, until you complete the CSC.
Once again, use it only as an emergency shutdown. Not to stop the motors after every landing.

 

[ringolong]

It's amazing how many people believe that DJI design engineers could be smart enough to create the Inspire but have the normal descent procedure kill the motors in flight.

Thanks for the information!

I had to ask to make sure after reading all the horror stories. I think this is why so many people are asking about this information, so there is nothing that should amaze you

 

[SanCap]

This is what a CSC maneuver looks like from a go pro on a Phantom 1. I did it because I had an uncommanded full power takeoff. You can hear the motor restart just before the Phantom hit the ground.

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[ringolong]

Your right. RTH is not the ideal way to land. It comes down with landing arms down (less stability) at maximum descend speed of 4m/sec, and vertical. The classic recipe for VRS (google that if you don't know what it means, a ton of discussions on the web about that).
Always descend in a slope preferably with the nose in the wind.

Different discussion but worth to mention I think.

I never use RTH to land. That was the first and hopefully the last time to execute it on this machine

I usually descend in a forward and then backward motion to keep things as stable as possible. I still need to adjust the vertical gains correctly for a smooth descend.

 

[lake_flyer]

I never use RTH to land. That was the first and hopefully the last time to execute it on this machine

I usually descend in a forward and then backward motion to keep things as stable as possible. I still need to adjust the vertical gains correctly for a smooth descend.

Well, I do use RTH quite a lot. Maybe because I like the ride back on the backseat. The return home procedure is bullet proof as long as there are sats and homepoint is locked.
But as soon as it's near I switch to normal and land myself, in an upwind slope. And lower the gear at 10 feet AGL, not sooner.

No harm in letting the bird fly back itself. It's only 1 waypoint

 

[The Editor]

That would make sense.

It can't be a faulty barometer if the same behaviour is replicated on the SIM. The Inspire doesn't move when using the SIM so no barometric data is changing.
Something else is afoot.

 

[Chris Hursey]

I descend with 100% down-stick often and for long periods and it NEVER turns off the motors.


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