Sudden Disconnection without RTH - Can anyone tell me what happened?

[RokkoRokko]

I flew to capture a ferry passing at breaker bay
then sudden disconnection from RC & no RTH - was allgood then gone
Now I have no drone

Can someone analyze my flight & tell me what happened

 

[iamcostas]

Battery Cell Deviation: How much is too much?

I was out flying my MP a few weeks back, using Litchi, when the controller showed a BATT ERROR (I don't remember the exact text). A little red balloon popped up in Litchi at the same time, but wasn't on the screen long enough to read it. I just figured I would check the logs to see what...

mavicpilots.com

 

[iamcostas]

 

[iamcostas]

Not so experienced, just guessing...

 

[slup]

I flew to capture a ferry passing at breaker bay
then sudden disconnection from RC & no RTH - was allgood then gone
Now I have no drone

Can someone analyze my flight & tell me what happened

Nah ... that cell deviation was way to small to have caused this ... the cells behaved until the bitter end & the log don't show a sudden death of a cell.

This flight was pretty straight forward, besides that you started it with only 62% battery ... perhaps earlier flights just before?

You quickly ascended up to 67m height & then pinned both aileron & elevator stick making you flying in a 45 degree angle compared to the yaw direction ... just in the end you fed in some rudder also.

Below show the red flight path together with the AC position when the log ends ... green bar = yaw direction & yellow tilt direction.



The battery info from the log doesn't show anything abnormal ... the log just ends at 67m height with a battery on 60% going with a heading speed just above 14m/s ... then nothing.



So ... nothing in the .TXT log give a reason for this, all very typical to either a electrical fault or a ejected battery that cuts the power making the motors stop & the RC connection being terminated.

Maybe some more can be discovered from the mobile device .DAT log ending with FLY063. Read up here how to retrieve --> Mavic Flight Log Retrieval and Analysis Guide (read under section 3.) Attach it then in a new post here.

 

[Deleted member 103366]

Can I ask why you lauched 2km from Wellington airport runway?

From New Zealand Airspace Maps for Drone Pilots | AirShare NZ hub for drones and UAVs

 

[tlswift58]

Can I ask why you lauched 2km from Wellington airport runway?

From New Zealand Airspace Maps for Drone Pilots | AirShare NZ hub for drones and UAVs

Looks to be outside any restricted zone, so what would be the issue?

 

[Meta4]

Looks to be outside any restricted zone, so what would be the issue?

That looks to be much too close to a large airport.
It doesn't explain the loss of signal but the error message earlier in the flight should be considered if looking for no RTH explanation.
Current RTH route will pass a no-fly zone. Pay attention to the aircraft's position to avoid RTH failure.
It might or might not be the explanation.

 

[Deleted member 103366]

Looks to be outside any restricted zone, so what would be the issue?

Look again

New Zealand Airspace Maps for Drone Pilots | AirShare NZ hub for drones and UAVs

Wondering where you can and can't fly your drone in New Zealand? Low Flying Zones UAVs are not permitted to fly in any Low Flying Zones, which are coloured orange. Military Operating Areas Permission from the administering authority is requested to fly in the green zones.

www.airshare.co.nz

 

[RokkoRokko]

Look again

New Zealand Airspace Maps for Drone Pilots | AirShare NZ hub for drones and UAVs

Wondering where you can and can't fly your drone in New Zealand? Low Flying Zones UAVs are not permitted to fly in any Low Flying Zones, which are coloured orange. Military Operating Areas Permission from the administering authority is requested to fly in the green zones.

www.airshare.co.nz

Blue Zone was unlocked - nowhere near a red zone

 

[RokkoRokko]

That looks to be much too close to a large airport.
It doesn't explain the loss of signal but the error message earlier in the flight should be considered if looking for no RTH explanation.
Current RTH route will pass a no-fly zone. Pay attention to the aircraft's position to avoid RTH failure.
It might or might not be the explanation.

If I had intercepted a no fly zone I woulda got a vocal warning & drone stop flying forward / into zone & hover at edge of it as it usually does - would still have had control

 

[slup]

Even though the restricted zone in the area could come into play in this case ... I doubt it due to a couple reasons.

First looking at the disconnect ... this was a Mavic 2, which haven't been prone to strangely & suddenly loose the connection as other AC like the MA2 & Mini2 . This at only 191m distance & totally without any signal disturbance at all before the log ends.


If then looking into the possible flight restrictions there out from the DJI FLY Safe ... which is what could prohibit a take off or induce a auto landing ...

Already at 4.4sec the HP is recorded, so it isn't like the AC is well on it's way when the position becomes apparent due to a lack of position fix at take off & the DJI FLY Safe kicks in. Instead this flight must have been authorized through the GO4 app as it's a blue zone which gives that possibility.


Still think's that a power loss in the most likely conclusion ... but as the log doesn't reveal the cause everything that remains is guesswork unfortunately.

@RokkoRokko ... have you tried to retrieve the mobile device DAT log yet?

 

[iamcostas]

Whatever it happened to your drone, how much confident will you feel with your next drone flight in the future?

 

[Deleted member 103366]

I am not suggesting the location had anything to do with the loss of the drone but I am questioning whether the flight should have been flown at all.

What do you mean by "unlocked"? I have seen mention of that in posts in here but get the impression it relates to DJI, which does seem odd to me.
So, to avoid doubt, who did you contact to "unlock" the flight?
If air traffic control than my concerns are groundless.

The two
"Current RTH route will pass a no-fly zone. Pay attention to the aircraft's position to avoid RTH failure."

messages started it, then a quick skim through NZ regs all mention staying more than 4km away from airports.

Intro to Part 101 rules for unmanned aircraft | aviation.govt.nz

www.aviation.govt.nz

states
"Stay 4km’s away from all aerodromes - unless you’ve got clearance from the aerodrome operator. See Aerodromes section for other conditions."
and the aerodrome section begins
"Under Part 101 Gyrogliders and Parasails, Unmanned Aircraft (including Balloons), Kites, and Rockets - Operating Rules, you must get an agreement from the aerodrome operator before flying your unmanned aircraft within 4 km of their aerodrome. This includes the helipads at hospitals, and also those used by helicopters conducting scenic flights.

Contact details for aerodrome operators can be found on the AirShare website."

There is a NZ CAA publication fly-the-right-way which states

"Know the no-fly zones It’s dangerous to fly drones anywhere other aircraft are operating. • Stay 4 km away from any airport – including helipads at hospitals and those used by sight-seeing aircraft.• Be aware that controlled airspace around airports extends well beyond the 4km limit – you must have clearance from Air Traffic Control to operate in that area.• "

 

[RokkoRokko]

Nah ... that cell deviation was way to small to have caused this ... the cells behaved until the bitter end & the log don't show a sudden death of a cell.

This flight was pretty straight forward, besides that you started it with only 62% battery ... perhaps earlier flights just before?

You quickly ascended up to 67m height & then pinned both aileron & elevator stick making you flying in a 45 degree angle compared to the yaw direction ... just in the end you fed in some rudder also.

Below show the red flight path together with the AC position when the log ends ... green bar = yaw direction & yellow tilt direction.

View attachment 123458

The battery info from the log doesn't show anything abnormal ... the log just ends at 67m height with a battery on 60% going with a heading speed just above 14m/s ... then nothing.

View attachment 123460

So ... nothing in the .TXT log give a reason for this, all very typical to either a electrical fault or a ejected battery that cuts the power making the motors stop & the RC connection being terminated.

Maybe some more can be discovered from the mobile device .DAT log ending with FLY063. Read up here how to retrieve --> Mavic Flight Log Retrieval and Analysis Guide (read under section 3.) Attach it then in a new post here.

It is like the battery ejected, aye... but I am sure it was secure - it was a Mavic 2 pro - warns if battery not secure

But I was maneuvering at the moment of disconnection

I wondered if I had pushed both sticks to centre by accident cutting the engines....

but that wouldn't have killed the connection as battery would be still active & I would been warned motors stopped & I could have restarted... surely

It does look like battery died suddenly or became disconnected as I maneuvered

Day was perfect - no wind

Another annoying thing was cache wasn't recording so no videos from flight

 

[RokkoRokko]

Even though the restricted zone in the area could come into play in this case ... I doubt it due to a couple reasons.

First looking at the disconnect ... this was a Mavic 2, which haven't been prone to strangely & suddenly loose the connection as other AC like the MA2 & Mini2 . This at only 191m distance & totally without any signal disturbance at all before the log ends.

View attachment 123498
If then looking into the possible flight restrictions there out from the DJI FLY Safe ... which is what could prohibit a take off or induce a auto landing ...

Already at 4.4sec the HP is recorded, so it isn't like the AC is well on it's way when the position becomes apparent due to a lack of position fix at take off & the DJI FLY Safe kicks in. Instead this flight must have been authorized through the GO4 app as it's a blue zone which gives that possibility.

View attachment 123499
Still think's that a power loss in the most likely conclusion ... but as the log doesn't reveal the cause everything that remains is guesswork unfortunately.

@RokkoRokko ... have you tried to retrieve the mobile device DAT log yet?

been looking, can't find it

 

[Deleted member 103366]

The CSC stick position will not stop the motors in mid air unless the drone thinks it has encountered an emergency or you changed the respone from "breakdown" to "Always" .

 

[RokkoRokko]

Whatever it happened to your drone, how much confident will you feel with your next drone flight in the future?

I have flown hundreds of flights - this the first issue like this - I will still be confident flying

I was rushing to get the ferry in right place so I may have slipped up securing the battery possibly, but then the Mav 2 Pro warns if battery is not secure before takeoff

 

[RokkoRokko]

The CSC stick position will not stop the motors in mid air unless the drone thinks it has encountered an emergency or you changed the respones from "breakdown" to "Always" .

didn't think this was issue, just something I considered

everything I am picking up suggests sudden battery failure

 

[iamcostas]

Just a new post maybe relative...

Battery from 94% to 0% Forced Landing (with flight log)

I had 100% charged 3 batteries last night and flew fine with 2 batteries. When I put the 3rd battery in it was at 98% and I flew for about 2 minutes and got forced landing message and battery indicator said 0%. Luckily I was able to land on the side of the road. A really scary situation as I was...

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