Mavic Pro Controller Communication Limits?

[Reelman67]

I am a relative newbie to the forum but my question is this....having a Mavic Pro....what constitutes an obstruction to the controller, such that communication would cease? I am referring to a video I just posted this morning where a respondent wished that I had overflown the Satsop cooling tower for a look downwards into the interior. I did not due to my concern that I would loose sight of the Mavic totally due to the massive concrete and steel structure itself, and perhaps lose control. I do not want to purposefully have the Mavic return on automated responses due to lack of controller communication. I was close to the tower (within 200'), and looking up, it is a gargantuan structure, and once reaching the top, to fly over the opening, would totally remove the drone from my view. It was a chance I did not want to take. Was I correct in my assessment of the situation? Comment?

 

[Former Member]

Obstructions can be structures, but a similar concern could be radio interference. You exercised good judgment by not flying outside VLOS, and not taking the risk.

 

[Meta4]

what constitutes an obstruction to the controller, such that communication would cease? I am referring to a video I just posted this morning where a respondent wished that I had overflown the Satsop cooling tower for a look downwards into the interior. I did not due to my concern that I would loose sight of the Mavic totally due to the massive concrete and steel structure itself, and perhaps lose control. I do not want to purposefully have the Mavic return on automated responses due to lack of controller communication. I was close to the tower (within 200'), and looking up, it is a gargantuan structure, and once reaching the top, to fly over the opening, would totally remove the drone from my view. It was a chance I did not want to take. Was I correct in my assessment of the situation?

If you fly behind the concrete and steel structure or to a position where it blocks the signal, you would lose signal.
But if it's a standard giant salt shaker type cooling tower, you should be able to fly above it and maintain an unobstructed line of sight if you are standing back from the base of the tower.

You should have practised RTH in controlled circumstances to understand how it works.
If you did fly to a position where the signal was blocked, the drone would initiate RTH after three seconds and retrace its path to regain signal.
You would not "lose control" except that control would have already been lost by flying to a point where the control signal was blocked.

 

[Reelman67]

Thanks for the response. It confirmed what I surmised. To get a good overflight of the tower, I needed to be further out to keep in VLOS. I've never had an auto-return to date, but have used the RTH feature. Been too careful. Had I flown the Mavic out of VLOS and lost contact, I believe the drone, as you stated, would have maintained the same altitude and reversed course to a point above me and descended to the point of beginning.

 

[Meta4]

I've never had an auto-return to date, but have used the RTH feature. Been too careful. Had I flown the Mavic out of VLOS and lost contact, I believe the drone, as you stated, would have maintained the same altitude and reversed course to a point above me and descended to the point of beginning.

It's a really good isea to do some experimenting with RTH to get a good understanding of what it does and how it does it so that when you need it or when it happens, it won't be a surprise.
Go to a large open area and fly out 100 feet and try activating RTH and cancelling to resume control.
Also try switching the controller off to simulate a lost control signal and watch what happens.
The day you need RTH is the worst day to start learning how it works.

 

[brett8883]

I am a relative newbie to the forum but my question is this....having a Mavic Pro....what constitutes an obstruction to the controller, such that communication would cease? I am referring to a video I just posted this morning where a respondent wished that I had overflown the Satsop cooling tower for a look downwards into the interior. I did not due to my concern that I would loose sight of the Mavic totally due to the massive concrete and steel structure itself, and perhaps lose control. I do not want to purposefully have the Mavic return on automated responses due to lack of controller communication. I was close to the tower (within 200'), and looking up, it is a gargantuan structure, and once reaching the top, to fly over the opening, would totally remove the drone from my view. It was a chance I did not want to take. Was I correct in my assessment of the situation? Comment?

@Reelman67 I don’t think you would have lost radio communication. I push the drone to its outer most limits on a daily basis and it’s remarkable how resilient the radio signal is.

Having said that you made the correct decision not to proceed due the fact that the drone would be outside of your visual line of sight if you did. Not only is it wise to keep the drone within your sight from an operational stand point it’s is also a requirement here in the US.

It would be a much better idea to position yourself in a a way that you could still see the drone when it overflew the cooling tower. This could also mean raising the altitude of the drone during overflight if that enabled you to see the drone. The FAAs 400 ft altitude limit does not apply if your drone is within 400 feet of a structure, however, you would still need to be able to maintain VLOS.

 

[Former Member]

@Reelman67 I don’t think you would have lost radio communication. I push the drone to its outer most limits on a daily basis and it’s remarkable how resilient the radio signal is.

Having said that you made the correct decision not to proceed due the fact that the drone would be outside of your visual line of sight if you did. Not only is it wise to keep the drone within your sight from an operational stand point it’s is also a requirement here in the US.

It would be a much better idea to position yourself in a a way that you could still see the drone when it overflew the cooling tower. This could also mean raising the altitude of the drone during overflight if that enabled you to see the drone. The FAAs 400 ft altitude limit does not apply if your drone is within 400 feet of a structure, however, you would still need to be able to maintain VLOS.

Remember to take into account Murphys Law.

 

[brett8883]

Remember to take into account Murphys Law.

That's true too!

 

[BobDoLe]

also.. i don't know about everyone else, but i've flown a few different mavic pros/platinums and they ALL drift into the concrete/steel structures once you get close enough. However, it is possible to get your shots without too much risk.
if i were you, i'd drive over onto keys rd s and try to get as much elevation as you can on that hill back there. it would seem that from there you could even put the mavic pro into the tower (not that you'd even need to get that close).
be sure to set to RTH on disconnect, but with a good amount of altitude so that it goes away from the tower. unfortunately, if it does disconnect, it will sit there and drift around a bit before RTH and so relying on RTH while disconnected within that kind of structure is not advisable IMO.

someone who isn't me has flown a mavic platinum over/around a much tighter coal burning stack (defunct, closed for years) as well as a chimney full of pigeons. he's a real weird guy, don't ask me what his problem is...

 

[Reelman67]

It's a really good isea to do some experimenting with RTH to get a good understanding of what it does and how it does it so that when you need it or when it happens, it won't be a surprise.
Go to a large open area and fly out 100 feet and try activating RTH and cancelling to resume control.
Also try switching the controller off to simulate a lost control signal and watch what happens.
The day you need RTH is the worst day to start learning how it works.

Yes, on a number of occasions, I have initiated RTH and have cancelled it prior to landing. I have never had an auto-return where I did not initiate it i.e. loss of signal, etc. I think I gave some respondents the impression I had never used RTH, which is not the case. I do have an excellent test area to try out features, and will have to implement the "loss of control signal" scenario.

 

[Reelman67]

@Reelman67 I don’t think you would have lost radio communication. I push the drone to its outer most limits on a daily basis and it’s remarkable how resilient the radio signal is.

Having said that you made the correct decision not to proceed due the fact that the drone would be outside of your visual line of sight if you did. Not only is it wise to keep the drone within your sight from an operational stand point it’s is also a requirement here in the US.

It would be a much better idea to position yourself in a a way that you could still see the drone when it overflew the cooling tower. This could also mean raising the altitude of the drone during overflight if that enabled you to see the drone. The FAAs 400 ft altitude limit does not apply if your drone is within 400 feet of a structure, however, you would still need to be able to maintain VLOS.

I agree with you, but I do have a question. It appears that VLOS is somewhat subjective. I have what I believe to be good visual acuity, but I have problems seeing my Mavic Pro after it travels several hundred feet from me, especially under various light conditions. I have considered this and have ordered a strobe light kit which should increase visibility of my drone at longer distances. I think to some, VLOS means an unobstructed view without trees, buildings, etc. at virtually any distance the signal can be transmitted (I am guilty of this, and so are many, many others). My understanding of the law is that the drone be within eyesight at all times, without aids. Am I correct?

 

[FoxhallGH]

Here's an interesting exploration of an abandoned Cooling Tower ...

 

[Meta4]

I think to some, VLOS means an unobstructed view without trees, buildings, etc. at virtually any distance the signal can be transmitted.

VLOS and LOS are two different things.
Regulations require VLOS and LOS is required by the laws of physics.
You could fly all the way to the moon and maintain LOS even though you lost VLOS at a few hundred feet.

 

[Thomas B]

VLOS and LOS are two different things.
Regulations require VLOS and LOS is required by the laws of physics.
You could fly all the way to the moon and maintain LOS even though you lost VLOS at a few hundred feet.

Well said.
Add strobes to add distance to VLOS and maintain enough altitude to see them.

 

[BobDoLe]

a heavy strobe would help add some distance, but i bet some mirrors or chrome/mirror tape would shine rrreal far away and weigh less.

 

[Thomas B]

a heavy strobe would help add some distance, but i bet some mirrors or chrome/mirror tape would shine rrreal far away and weigh less.

Strobes are light... I use 4 ARC2s in Aerial Pixel mounts Easy on, easy off. No performance differences noted on Spark, MPP, or M2P but ease of visualization and reacquisition are better by a long distance. Try the tape, but it will be out of VLOS quickly and also you depend on the angle of incidence with the sun in all instances.

 

[BobDoLe]

Strobes are light... I use 4 ARC2s in Aerial Pixel mounts Easy on, easy off. No performance differences noted on Spark, MPP, or M2P but ease of visualization and reacquisition are better by a long distance. Try the tape, but it will be out of VLOS quickly and also you depend on the angle of incidence with the sun in all instances.

i stand corrected - those strobes are 4 grams!