Primarily for general aviation discussion, but other aviation topics are also welcome.
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By MattL
#1803713
Drones aren’t going to go away any time soon (and I think you’ll see increasing investment and government support) so as a community we should focus on lobbying for them to see and avoid us; for that we need cooperating EC. The alternative is increasing swathes of restricted airspace and more exclusions I fear.
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By JAFO
#1803716
GrahamB wrote:
JAFO wrote:I did know what BVLOS stood for but it begs the question, can you have a line of sight which is anything other than visual?

Radio waves.


Not line of sight then, is it, Graham? The term line of sight is used to describe the distance where radio waves of certain frequencies may be reasonably expected to be received but the fact that it's line of sight quite obviously relates to what would also, given the right conditions, be visual.
#1803718
JAFO wrote:Not line of sight then, is it, Graham? The time line of sight is used to describe the distance where radio waves of certain frequencies may be reasonably expected to be received but the fact that it's line of i]sight[/i] quite obviously relates to what would also, given the right conditions, be visual.

Read up any description of how VORs work, and they are described as relying on 'line-of'sight', because VHF can't propagate along the ground, as lower frequency NDBs can, for example.
Wikipedia wrote:VOR stations rely on "line of sight" because they operate in the VHF band—if the transmitting antenna cannot be seen on a perfectly clear day from the receiving antenna, a useful signal can still be received. This limits VOR (and DME) range to the horizon—or closer if mountains intervene.

BoldMethod wrote:5) Line Of Sight
VORs are based on line-of-sight. If terrain or the horizon obscures a direct path between your airplane and the VOR, it will be unusable.

etc.
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By JAFO
#1803719
@GrahamB, I know how VORs work, I know how radios work, the Royal Air Force was kind enough to train me as a radio, radar and electronic warfare specialist, so they did mention how these things work.

My point is the word SIGHT - that cannot be anything other than visual regardless of what it is then later applied to.
By johnm
#1803720
"Line of sight" typically applies to the whole spectrum of electromagnetic radiation and is describing one aspect of its propagation. [/pedant]
#1803723
Line of sight does not mean that literally the generator must be seen: It does not take into account the receiver’s ‘visual acuity ‘; it merely means there must not be any physical object between transmitter and receiver that would impede the passage of the particular radiated signal.
Right up to a DOC in the case of VORs of 50 NM or more.
That would require seriously sharp visual acuity if the phrase ‘line of sight’ were to be taken literally .
#1803726
JAFO wrote:@GrahamB, I know how VORs work, I know how radios work, the Royal Air Force was kind enough to train me as a radio, radar and electronic warfare specialist, so they did mention how these things work.

In that case you should know that the term is applied in its non-literal sense to radio waves. :roll: :)
#1803734
My understanding of BVLOS in the context of controlling a drone is when it disappears over the horizon.

For takeoff/landing, an operator controls the craft in the same sort of way a modeller does. You know that bit where when it’s flying towards you control inputs are opposite for roll.

The transit is then autonomous BVLOS.
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By JAFO
#1803754
GrahamB wrote:
JAFO wrote:@GrahamB, I know how VORs work, I know how radios work, the Royal Air Force was kind enough to train me as a radio, radar and electronic warfare specialist, so they did mention how these things work.

In that case you should know that the term is applied in its non-literal sense to radio waves. :roll: :)


Of course I know that, Graham. :roll: My point was that the term "visual line of sight" is a tautology. I sincerely wish I hadn't bothered making it.
#1803775
Just to point out that the term "Line of sight" in droneland relates to the restriction on hobby and work drones that the operator must be able to see the craft at all times with the naked eye unless they apply for and receive a dispensation for that flight.

Rob P
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By JAFO
#1803793
Rob P wrote:Just to point out that the term "Line of sight" in droneland relates to the restriction on hobby and work drones that the operator must be able to see the craft at all times with the naked eye unless they apply for and receive a dispensation for that flight.

Rob P


Do they have to see it visually, Rob? :wink: :D
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