FAR 107.31 Visual line of sight aircraft operation. Conflicting language?

slats · Mar 3, 2019

I'm interested your thoughts about FAR 107.31 which reads as follows:

§107.31 Visual line of sight aircraft operation.
(a) With vision that is unaided by any device other than corrective lenses, the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system must be able to see the unmanned aircraft throughout the entire flight in order to:
(1) Know the unmanned aircraft's location;
(2) Determine the unmanned aircraft's attitude, altitude, and direction of flight;
(3) Observe the airspace for other air traffic or hazards; and
(4) Determine that the unmanned aircraft does not endanger the life or property of another.
(b) Throughout the entire flight of the small unmanned aircraft, the ability described in paragraph (a) of this section must be exercised by either:
(1) The remote pilot in command and the person manipulating the flight controls of the small unmanned aircraft system; or
(2) A visual observer.

It seems that paragraph (a) conflicts with paragraph (b). Here's why I think so:

Paragraph (a) is inclusive of all 3 possible roles when flying - "...the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system...".

Paragraph (b) states - "...(1) The remote pilot in command and the person manipulating the flight controls of the small unmanned aircraft system; or (2) A visual observer.

I'm not suggesting that its ever acceptable to not have a visual contact on your aircraft. I'm just wondering if others see the same conflict in the regulation that I do.

shooter · Mar 4, 2019

slats said:
I'm interested your thoughts about FAR 107.31 which reads as follows:

§107.31 Visual line of sight aircraft operation.
(a) With vision that is unaided by any device other than corrective lenses, the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system must be able to see the unmanned aircraft throughout the entire flight in order to:
(1) Know the unmanned aircraft's location;
(2) Determine the unmanned aircraft's attitude, altitude, and direction of flight;
(3) Observe the airspace for other air traffic or hazards; and
(4) Determine that the unmanned aircraft does not endanger the life or property of another.
(b) Throughout the entire flight of the small unmanned aircraft, the ability described in paragraph (a) of this section must be exercised by either:
(1) The remote pilot in command and the person manipulating the flight controls of the small unmanned aircraft system; or
(2) A visual observer.

It seems that paragraph (a) conflicts with paragraph (b). Here's why I think so:

Paragraph (a) is inclusive of all 3 possible roles when flying - "...the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system...".

Paragraph (b) states - "...(1) The remote pilot in command and the person manipulating the flight controls of the small unmanned aircraft system; or (2) A visual observer.

I'm not suggesting that its ever acceptable to not have a visual contact on your aircraft. I'm just wondering if others see the same conflict in the regulation that I do.

Typical government inelegant wording.

Here's how I see it:

Solo PIC is flying: PIC must maintain VLOS

Person manipulating the flight controls is flying, PIC is also present: Both maintain VLOS

PIC is flying, but has a visual observer: Either can maintain VLOS

But, I could be wrong...I've been wrong before...like, when I got married the first time...ya know? ;-)

slats · Mar 4, 2019

shooter said:
Typical government inelegant wording.

Here's how I see it:

Solo PIC is flying: PIC must maintain VLOS

Person manipulating the flight controls is flying, PIC is also present: Both maintain VLOS

PIC is flying, but has a visual observer: Either can maintain VLOS

But, I could be wrong...I've been wrong before...like, when I got married the first time...ya know? ;-)

I made that same mistake ;-)

That aside, I've been in aviation for a long time and I'm usually pretty good at deciphering the legalese contained in the regs. This one does seem to conflict with itself though. The bottom line here is that the Remote Pilot is ultimately responsible for everything that happens on any given flight and it would be prudent to maintain VLOS at all times to avoid having to debate the language in that particular FAR with the "Administrator".

drone Pilot · Mar 4, 2019

OR A VISUAL OBSERVER " is the loophole in this regulation, that allows the interpretation for the PIC to fly FPV.

slats · Mar 4, 2019

drone Pilot said:
OR A VISUAL OBSERVER " is the loophole in this regulation, that allows the interpretation for the PIC to fly FPV.

That may be the case but the wording in para (a) and (b) still seems to conflict. I would even take this one step further and suggest that both paragraphs (a) and (b) are not required. One paragraph is sufficient here unless there is some difference in meaning between the two paragraphs that the FAA is trying to convey. I don't see it though.
Maybe I'm too focused on what I perceive to be a wording conflict and I'm missing something.

You bring up an interesting point though about FPV which brings a couple of questions to mind: 1) What percentage of the operations conducted by Part 107 certificate holders are actually commercial in nature? 2) For those Part 107 certificate holders that are conducting commercial flights, how often are FPV goggles used during those flights? Maybe these questions should be part of a new thread...

R Martin · Mar 4, 2019

slats said:
You bring up an interesting point though about FPV which brings a couple of questions to mind: 1) What percentage of the operations conducted by Part 107 certificate holders are actually commercial in nature? 2) For those Part 107 certificate holders that are conducting commercial flights, how often are FPV goggles used during those flights? Maybe these questions should be part of a new thread...

§107.31 Visual line of sight aircraft operation.
(a) With vision that is unaided by any device other than corrective lenses, the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system must be able to see the unmanned aircraft throughout the entire flight in order to:

(1) Know the unmanned aircraft's location;

(2) Determine the unmanned aircraft's attitude, altitude, and direction of flight;

(3) Observe the airspace for other air traffic or hazards; and

(4) Determine that the unmanned aircraft does not endanger the life or property of another.

(b) Throughout the entire flight of the small unmanned aircraft, the ability described in paragraph (a) of this section must be exercised by either:

(1) The remote pilot in command and the person manipulating the flight controls of the small unmanned aircraft system; or

(2) A visual observer.

The emphasis above is mine. So the way I read the regs the answer to your second question is -0-. Under Part 107, FPV goggles are not allowed. You would have to be flying recreationally to use them, or at least that is my take.

R Martin · Mar 4, 2019

drone Pilot said:
OR A VISUAL OBSERVER " is the loophole in this regulation, that allows the interpretation for the PIC to fly FPV.

The wording of the reg says that everyone involved in the flight must be able to see the aircraft at all times....

§107.31 Visual line of sight aircraft operation.
(a) With vision that is unaided by any device other than corrective lenses, the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system must be able to see the unmanned aircraft throughout the entire flight in order to...

Again, that is the way I interpret the regs. Your results may vary by mileage and testosterone levels....

Here is the link if you care to check for yourself.
§107.31 Visual line of sight aircraft operation.

slats · Mar 4, 2019

R Martin said:
The wording of the reg says that everyone involved in the flight must be able to see the aircraft at all times....

§107.31 Visual line of sight aircraft operation.
(a) With vision that is unaided by any device other than corrective lenses, the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system must be able to see the unmanned aircraft throughout the entire flight in order to...

Again, that is the way I interpret the regs. Your results may vary by mileage and testosterone levels....

Here is the link if you care to check for yourself.
§107.31 Visual line of sight aircraft operation.

I've read the reg several times - its actually part of my original post. I just see a conflict between paragraphs (a) and (b). I'm not trying to suggest that I would do anything other than maintain VLOS - I'm just curious if anyone else reads 107.31 the way I do. It's helpful to hear other perspectives on things.

RickMC · Mar 4, 2019

Paragraph b says that the ability described in Paragraph A must be exercised by the remote pilot OR the visual observer. Paragraph B is what I would go with. It says “OR”, not “BOTH”. So why wouldn’t FPV be allowed if the pilot has a visual observer?

RickMC · Mar 4, 2019

R Martin said:
The wording of the reg says that everyone involved in the flight must be able to see the aircraft at all times....

§107.31 Visual line of sight aircraft operation.
(a) With vision that is unaided by any device other than corrective lenses, the remote pilot in command, the visual observer (if one is used), and the person manipulating the flight control of the small unmanned aircraft system must be able to see the unmanned aircraft throughout the entire flight in order to...

Again, that is the way I interpret the regs. Your results may vary by mileage and testosterone levels....

Here is the link if you care to check for yourself.
§107.31 Visual line of sight aircraft operation.

Yeah but then it says in Paragraph B that the ability described in A has to be exercised by the PIC and person manipulating the flight controls OR the visual observer. It doesn’t say “ALL THREE” have to. I think paragraph A just implies that one or more of those roles has to maintain VLOS depending on what roles are actually involved in the operation. I don’t think it implies that if all of those roles are involved in an operation that they all have to maintain VLOS at the same time. What’s the point of even having a visual observer if the pilot can never fly beyond VLOS? If all of them had to maintain VLOS why would they even have Paragraph B that’s puts a big “OR” in there. I could be wrong, that’s just the way I see it.

slats · Mar 4, 2019

RickMC said:
Yeah but then it says in Paragraph B that the ability described in A has to be exercised by the pilot OR the visual observer. It doesn’t say “both” have to. I think paragraph A just implies that depending on whether or not all those roles are involved in the operation, one of them has to maintain VLOS, not all at the same time, even though it says “and” between visual observer and person manipulating flight controls. What’s the point of even having a visual observer if the pilot can never fly beyond VLOS? If all of them had to maintain VLOS why would they even have Paragraph B that’s puts a big “OR” in there. I could be wrong, that’s just the way I see it.

I'm glad you explained it that way. After your first post, I was starting to read it that way as well. Thanks for imparting your wisdom!

RickMC · Mar 4, 2019

slats said:
I'm glad you explained it that way. After your first post, I was starting to read it that way as well. Thanks for imparting your wisdom!

It’s just my interpretation. If all of them had to maintain line of site at the same time, why even bother with paragraph B? Paragraph A would be sufficient. I think that paragraph just means that if there is no visual observer then the PIC and person manipulating flight controls have to maintain VLOS. In the case that a visual observer is used then the other two roles don’t have to maintain VLOS as long as the visual observer is. If all of them had to maintain VLOS at the same time the language in paragraph B would say “AND”, not “OR”

R.Perry · Mar 4, 2019

You want to have fun, pickup a current copy of FAA regulations and you will find the same thing throughout, don't expect the government and logic to have much in common.

drone Pilot · Mar 4, 2019

language used by the FAA was probably written by attorneys, who needed to justify future income with vagueness.

Phaedrus · Mar 5, 2019

This may help:

5.7 VLOS Aircraft Operation. The remote PIC and person manipulating the controls must be able to see the small UA at all times during flight. Therefore, the small UA must be operated closely enough to the CS to ensure visibility requirements are met during small UA operations. This requirement also applies to the VO, if used during the aircraft operation. However, the person maintaining VLOS may have brief moments in which he or she is not looking directly at or cannot see the small UA, but still retains the capability to see the UA or quickly maneuver it back to VLOS. These moments can be for the safety of the operation (e.g., looking at the controller to see battery life remaining) or for operational necessity. For operational necessity, the remote PIC or person manipulating the controls may intentionally maneuver the UA so that he or she loses sight of it for brief periods of time. Should the remote PIC or person manipulating the controls lose VLOS of the small UA, he or she must regain VLOS as soon as practicable. For example, a remote PIC stationed on the ground utilizing a small UA to inspect a rooftop may lose sight of the aircraft for brief periods while inspecting the farthest point of the roof. As another example, a remote PIC conducting a search operation around a fire scene with a small UA may briefly lose sight of the aircraft while it is temporarily behind a dense column of smoke. However, it must be emphasized that even though the remote PIC may briefly lose sight of the small UA, he or she always has the see-and-avoid responsibilities set out in part 107, §§ 107.31 and 107.37. The circumstances of what would prevent a remote PIC from fulfilling those responsibilities will vary, depending on factors such as the type of UAS, the operational environment, and distance between the remote PIC and the UA. For this reason, there is no specific time interval that interruption of VLOS is permissible, as it would have the effect of potentially allowing a hazardous interruption or prohibiting a reasonable one. If VLOS cannot be regained, the remote PIC or person manipulating the controls should follow pre-determined procedures for a loss of VLOS. These procedures are determined by the capabilities of the sUAS and may include immediately landing the UA, entering hover mode, or returning to home sequence. Thus, the VLOS requirement would not prohibit actions such as scanning the airspace or briefly looking down at the small UA CS.

https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_107-2.pdf?fbclid=IwAR3bUEEhVhySjPqC9AcR8br1KeFsOCRe9TxOkyOXDhGCW3yqiq8lgCognfU

R Martin · Mar 5, 2019

slats said:
I've read the reg several times - its actually part of my original post. I just see a conflict between paragraphs (a) and (b). I'm not trying to suggest that I would do anything other than maintain VLOS - I'm just curious if anyone else reads 107.31 the way I do. It's helpful to hear other perspectives on things.

What I read in the 3D perspective is you need to know where your aircraft is and you need to know where it is going at any given time. 107.31 a1 deals with the where in the now time frame and 107.31 a2 deals in the where in the near future. The most helpful thing I learned in my original training was that we generally think in gray where if there is a loophole (or the implication of a loophole) then it is admissible to circumvent the regs. In this context, the rule are actually black and white. It is allowed or it is not. This has helped me get through a lot of the regs and understand them a little better. And again, this is just my read on things but it has made developing our program a whole lot easier when it came to the op manual and AFMs.

drone Pilot · Mar 5, 2019

'where if there is a loophole (or the implication of a loophole) then it is admissible to circumvent the regs.' The larger argument that no one has commented on, Will the courts uphold an FAA prosecution based on unclear ambiguous language ?

R Martin · Mar 5, 2019

drone Pilot said:
The larger argument that no one has commented on, Will the courts uphold an FAA prosecution based on unclear ambiguous language ?

Are you willing to bet your paycheck or personal freedom on it? Or is it just a lot more convenient to follow the regs instead of trying to find a way around it? Its the difference between being a UAS pilot or just another putz with a drone.

Phaedrus · Mar 5, 2019

Did anyone read the info I posted above. It specifically addresses the topic of this thread??

Phaedrus · Mar 5, 2019

R Martin said:
Or is it just a lot more convenient to follow the regs instead of trying to find a way around it? Its the difference between being a UAS pilot or just another putz with a drone.

Are you serious? You feel that true professional try to find ways to work around the rules? You think the folks sitting up front on your commercial airline flights have that attitude? Most would consider them professionals, or are they just "putzes with airplanes"?? for following the rules?