Really Strange Flight - Any Ideas?

[Zeke]

I planned doing some practice flights yesterday, but the first flight of the day went really sideways and I'm not quite sure why. Anytime I fly I always manually update the home position, and on this flight I didn't even get that far away (885') when suddenly the radio signal dropped from 81% to 8%. Clear LOS, no obstructions. When I realized I no longer had control I hit RTH a few times and finally the drone started coming home - or so I thought. The drone actually flew right over me and kept going, totally freaked me out. At this point on the screen I switched over to map mode so I could track it. The controller was reading 0' to home, but it was well behind me at this point. I hit the pause button and thankfully the flight stopped. I tried to manually turn the drone and fly back to me, but I couldn't get a response. I tried moving backwards since it was pointing away, but nothing (on the map). Then suddenly I could hear it overhead, and it was back within sight. From that point on I managed to bring it back safely. I've never had anything like this happen before, and the only difference in this flight was that I'd attached a Marco Polo transmitter to the rear of the drone, just trying something new. Early in the flight as I was panning the gimbal down I had some sort of warning flash across the controller, all I caught was the word "wheel" then it was gone and never showed again. I can't find this event anywhere in the logs, I hoped I might. I stopped immediately and panned up and down a few times, and everything was fine. I've attached the .txt file, but for some reason this site won't allow me to upload the CSV? if anyone has any thoughts I'd love to hear them!

 

[sar104]

The aircraft did return to the home point correctly under RTH, but you cancelled RTH and flew it away by applying forward elevator. It re-engaged failsafe RTH after losing signal, as you mentioned, and it returned a second time:

 

[Zeke]

Thank you! When you say "elevator" this means gaining altitude? Or moving forward?

Do you have any thoughts on why I lost signal so close to the controller? When I fired the drone up I didn't get any interference warnings, just the airport one (although I was outside the airspace).

 

[Thomas B]

Thank you! When you say "elevator" this means gaining altitude? Or moving forward?

The stick command to gain altitude.

 

[Zeke]

The stick command to gain altitude.

Thank you. Slowly learning... ;-)

 

[slup]

Thank you! When you say "elevator" this means gaining altitude? Or moving forward?

Do you have any thoughts on why I lost signal so close to the controller? When I fired the drone up I didn't get any interference warnings, just the airport one (although I was outside the airspace).

The stick command to gain altitude.

No ... throttle is used to change altitude. Elevator is used for horizontal forward/backward speed... if on stick mod 2

 

[slup]

The aircraft did return to the home point correctly under RTH, but you cancelled RTH and flew it away by applying forward elevator. It re-engaged failsafe RTH after losing signal, as you mentioned, and it returned a second time:

View attachment 95607

View attachment 95606

Agree with you @sar104 ... only 2 things that puzzles me but those might have to do with that connection glitch just over the HP when returning.

Usually when cancelling RTH a DropGohome command is shown ... then it was a half negative throttle during 3sec without any height change ???

 

[Thomas B]

No ... throttle is used to change altitude. Elevator is used for horizontal forward/backward speed... if on stick mod 2

My statement is correct. I think we just have a semantics problem... here’s the manual on control stick commands and what they do. Default is mode 2.

 

[Old Cajun]

The antennas are directional, max signal off the side of the antenna. There is no signal off the ends of the antennas. If the ends of the antennas are pointed up, a drone overhead will not get a good signal. Never point the ends of the antennas toward your drone.

 

[slup]

My statement is correct. I think we just have a semantics problem... here’s the manual on control stick commands and what they do. Default is mode 2.
View attachment 95610

It can be that I'm not native English speaking & misunderstand you Thomas then I stand corrected, but ...

It's established that the OP applied Elevator above the HP & started to fly away from the HP at the same height as the AC arrived.
Right stick Elevator is used for forward & backwards movement & that match up with the log.

 

[Thomas B]

It can be that I'm not native English speaking & misunderstand you Thomas then I stand corrected, but ...

It's established that the OP applied Elevator above the HP & started to fly away from the HP at the same height as the AC arrived.
Right stick Elevator is used for forward & backwards movement & that match up with the log.

View attachment 95611

Agree.
We are saying the same thing.
Recommend Op refer to the diagrams we both posted. They are in complete agreement.

 

[sar104]

It can be that I'm not native English speaking & misunderstand you Thomas then I stand corrected, but ...

It's established that the OP applied Elevator above the HP & started to fly away from the HP at the same height as the AC arrived.
Right stick Elevator is used for forward & backwards movement & that match up with the log.

View attachment 95611

No - your understanding is correct. The elevator controls the pitch - i.e. moves the aircraft fowards/backwards. The throttle controls ascent/descent.

 

[Zeke]

The aircraft did return to the home point correctly under RTH, but you cancelled RTH and flew it away by applying forward elevator. It re-engaged failsafe RTH after losing signal, as you mentioned, and it returned a second time:

View attachment 95607

View attachment 95606

Disregarding the whole "elevator" question for the moment, I recall specifically at some point in the middle of all of this, the controller said the aircraft was home, but it was nowhere in sight - which is what started amping up my concern level. Thoughts?

 

[sar104]

No ... throttle is used to change altitude. Elevator is used for horizontal forward/backward speed... if on stick mod 2

The term elevator applies to the control that affects pitch - it's independent of which stick is doing it.

 

[sar104]

Disregarding the whole "elevator" question for the moment, I recall specifically at some point in the middle of all of this, the controller said the aircraft was home, but it was nowhere in sight - which is what started amping up my concern level. Thoughts?

It was home, directly above you at a height of 230 ft. Presumably you simply couldn't see or hear it.

 

[Zeke]

The antennas are directional, max signal off the side of the antenna. There is no signal off the ends of the antennas. If the ends of the antennas are pointed up, a drone overhead will not get a good signal. Never point the ends of the antennas toward your drone.

I believe the antennas on the controller have an indent at about the 45 degree mark to ensure the wide flat face (not the sides) are aimed at the drone. You are correct that no signal emanates from the ends/tips.

 

[slup]

Disregarding the whole "elevator" question for the moment, I recall specifically at some point in the middle of all of this, the controller said the aircraft was home, but it was nowhere in sight - which is what started amping up my concern level. Thoughts?

Did you in that moment push the RTH button again ..?

 

[Thomas B]

No - your understanding is correct. The elevator controls the pitch - i.e. moves the aircraft fowards/backwards. The throttle controls ascent/descent.

For the drone likely best for OP to understand what motions of the drone are to be expected with stick movements.

 

[sar104]

Agree with you @sar104 ... only 2 things that puzzles me but those might have to do with that connection glitch just over the HP when returning.

Usually when cancelling RTH a DropGohome command is shown ... then it was a half negative throttle during 3sec without any height change ???

I think that some of the command data was lost during the periods of signal loss that you can see in the status trace in the graph above.

 

[slup]

The term elevator applies to the control that affects pitch - it's independent of which stick is doing it.

Yep correct & agreed ... I'm only to much into the CsvView point of presenting it, there you have to figure out which stick mode it is as for instance the signal RC:throttle is the left stick forward/backwards but if in mode 1 or 3 that signal show elevator inputs.