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Line of sight or visual range terminology
1085 14 2017-8-18
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Fingers
Second Officer
Flight distance : 1321293 ft
United Kingdom
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I certainly don't want to be a geek or preacher on here, but are we all getting our terminology wrong with regards to 'line of sight'?
I work in communications / radars world and, for me, I think we might be. Line of sight LOS doesn't mean you have to be able to visually see (resolve) the target with the naked eye. It just means you've got an unobstructed view; obstructions could be buildings, wood lines, mountains or (as if often the case in the comms radar world) the curvature of the earth (theoretically you could lose sight of a Mavic due to curvature of the earth as the horizon is only around 5km away for a 6 foot bloke or lady; one for another discussion).  Terminology for this would be BLOS, beyond line of sight.

When we can see a target / object visually, we call this visual range.   Visual range can be increased with the use of vision aids (binos for example).   

A decent analogy would be - Me and my Mavic have LOS with GPS sats, giving me my GPS signal. Some GPS sats are BLOS (due to curvature of the earth). None are within my visual range. My television aerial has LOS with the transmitter station, but when I stand on my roof I can't see it visually...you get the picture.

I'm a cautious Mavic pilot. Yet, I often fly my Mavic beyond my visual range (for my eyes probably 250meters). I consider this safe though, as I always maintain LOS. Becasue I maintain LOS, I can see larger items that my Mavic my be hazardous towards; people, vehicles, power cables, emergency aircraft etc and I can respond ackordingly.   

So my question is, should I be flying my Mavic within Visual range, or maintain Line of Sight or both?
2017-8-18
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Lucas775
Captain
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United States
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I would say both if you want to stay safe then again after 500 ft or so it is hard to see the Mavic.  Maybe have a spotter with binoculars
2017-8-19
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Jenee 2
Captain
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Australia
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I think most people should abide by the rules of the country they are flying in as that will determine what they should do.
Here in Australia, it is clearly stated in our rules:

You must only fly by visual line of sight (VLOS)-close enough to see, maintain orientation and achieve accurate flight and tracking.
2017-8-19
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DroneFlying
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Flight distance : 10774613 ft
United States
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The phrase you're looking for is "visual line of sight" (VLOS), and yes that's technically different from (simple) "line of sight" (LOS). I believe that in the U.K. (as in the U.S. and many other countries) you're supposed to only fly within VLOS: Recreational Drone Flights

Yes, LOS and VLOS are used somewhat interchangeably on forums like this one, but I believe most of the time people are aware of the difference. The bigger problem with "LOS" is that sometimes newbies interpret that as a reference to "loss of signal", which is somewhat relevant to flying drones but obviously a completely different thing.
2017-8-20
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DroneFlying
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United States
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Lucas775 Posted at 2017-8-19 06:55
I would say both if you want to stay safe then again after 500 ft or so it is hard to see the Mavic.  Maybe have a spotter with binoculars

In the U.S., at least, using a visual observer (VO) only keeps the FAA happy when it's a non-recreational (107) flight, and even then the only visual aids they allow to maintain VLOS are corrective lenses (glasses and contacts).
2017-8-20
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hallmark007
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Ireland
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You are expected not to fly BVLOS (beyond), the term LOS is what most use as to explain LOS from radio to Aircraft, in order to fly BVLOS you would need a spotter, some countries don't allow a spotter unless you are in direct communication and have permission.
I don't think loosing VLOS for a couple of seconds will be that serious but it is expected that you try to regain VLOS asap .

While it seems a bit harsh it is the general rule in most countries.
2017-8-20
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calmari
lvl.4
Flight distance : 64944 ft
United Kingdom
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In the UK you must legally keep your device within your 'visual line of sight' at all times. The law is based on the clear premise that if you can't see your drone, you can't control your drone. 500m is the max distance CAA puts on it.
2017-8-20
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Fingers
Second Officer
Flight distance : 1321293 ft
United Kingdom
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I wish I could see my Mavic at 500m, with these old eyeballs!   
2017-8-20
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calmari
lvl.4
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Fingers Posted at 2017-8-20 07:08
I wish I could see my Mavic at 500m, with these old eyeballs!

I know, me too
2017-8-20
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Maveriksam
Second Officer
Flight distance : 417500 ft
United Kingdom
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I'm lucky to see my MP 10mtrs away with these on.
2017-8-20
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QuadKid
Captain
Flight distance : 482349 ft
United States
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May find this useful for Acronyms

https://www.rcgroups.com/forums/ ... n%21-%28GLOSSARY%29
2017-8-20
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Bekaru Tree
Captain
Flight distance : 15513100 ft
South Africa
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Strictly speaking - both LOS and VLOS. If in VLOS you can/should always see the drone which means it can see you/RC and therefore LOS is ipsofacto maintained. At the least though you must have LOS. Many of do fly beyond visual ability because mavic has the potential and camera feed allows safe flying beyond actual eye on visibility of drone - but risk of losing drone goes up if a bunch of bad circumstance comes into play; Stictly speaking - both : in reality - at least LOS. ensure RTH is set if radio signal is lost.
2017-8-20
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Fingers
Second Officer
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United Kingdom
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Maveriksam Posted at 2017-8-20 09:01
I'm lucky to see my MP 10mtrs away with these on.
https://contactsadvice.com/wp-content/uploads/2017/05/Misight-Contact-Lens-thick-glasses.jpg[/img]

Brilliant.
2017-8-20
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DJI Susan
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The above discussion make sense. Flight safety is always top priority. Take care.
2017-8-27
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RobDownUnder
Second Officer
Flight distance : 103609 ft
Australia
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Mavic is little more than a spot at 50mtrs altitude and 400 mtrs  horizontally. This is also subject to background. The tree line across the valley reduces the lateral distance substantially.
2017-8-28
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