Droney McDroneface: Day 2 (Air Law)

Today we covered air law, and charts and classes of air space and NOTAMs (Notice to Airmen). The charts and air space are pretty simple and there is a really cool app / website (skydemon) which allows you to point and see what restrictions and notices apply where you are. That was the easy bit. The hard bit is air law!

The reason it is hard is the vagueness, and stupidity, of the laws around this whole area.

There are general requirements to ensure flight is safe and to avoid collisions and so on, but the main two clauses of the Air Navigation Order 2009 are section 166 and 167. These two rules cover, basically, drones, and drones that are equipped for surveillance.

The drone we have is a Phantom 4 which falls in the ≤7kg weight class. What is interesting is that if it did not have a camera, only clause 166 would apply, and this has some moderately flexible rules...
  • Don't drop anything from the aircraft!
  • Only fly if you think it safe, duh.
  • Fly only in visual line of sight (deemed to be 500m horizontally which you cannot really see the drone at, but can see other aircraft, which is what matters). In practice you need not to fly so high as to be unable to see it as well.
  • Don't fly commercially without a PFAW (Permission For Aerial Works) from CAA
This is quite good - there is not even a height restriction or any need to obey controlled airspace! It is sensible as a courtesy to notify ATC (Air Traffic Control) but not a requirement. There are types of air space that prohibit any flight, but the controlled space is a big issue as that covers large areas (e.g. Bracknell is within Heathrow space) so not having that issue is huge. The requirements change once over 7kg. Basically, providing you are "safe" you can fly a ≤7kg drone most places even in towns and cities, even quite high, even if near people or vehicles or property, if it does not have surveillance equipment.

Update: It is worth pointing out that there are a load of general restrictions, such as not endangering other aircraft, which effectively place some limitations on what you do even under section 166. Even so, 166 is pretty flexible.

Section 167 is where it gets odd. Bear in mind these regulations are meant to relate to safety. This section applies to drones with surveillance equipment (e.g. a camera) which my Phantom 4 has, as do many drones. Why separate safety rules apply for drones with a camera is beyond me! The rules are much more onerous, covering those in 166 (above) plus...
  • Not over, or within 150m of a congested area
  • Not over, or within 150m of an organised assembly of 1,000 or more people
  • Not within 50m of a vessel, vehicle, or structure not under your control (30m during take-off or landing)
  • Not within 50m or a person (apart from pilot of persons directly under his control)
There are big issues with the wording - for a start the "not within 30m of a person" during take off or landing does not actually stop the "not within 50m or a person" rule. That rule should have an "except for take-off of landing" and does not have it. Really bad drafting. The other issue is the "Not within 50m of a structure not in control" does not stop the "over or within 150m of a congested area". Congested area includes anywhere used residentially, so a house is a congested area if in a city, town or settlement, so even with permission and control of the home owner you still cannot be over or within 150m!

In practice it seems to be interpreted that the 30m applies for take-off and landing not the 50m, and in practice it seems the structure you have control over is allowed within the 150m, but not within 150m of a neighbour or someone you do not control! Well, we hope, but the way the rules are interpreted is not 100% clear!

There were interesting discussion of vehicles and hence roads. Being 50m from a road could be a pain, but actually the rule is 50m from a vehicle. So we think, if the road is clear of vehicles (that are not under our control) we could take off near the road and get to 50m high. The rules do not say the 50m or 150m is horizontal, so 50m high and not actually over a vehicle would seem to be OK. But to make sure you are safe you have to have some procedures to cover checking the road is clear during take off and landing near the road somehow.

Another discussion is congested areas and the definition which is: ‘Congested area’ in relation to a city, town or settlement, means any area which is substantially used for residential, industrial, commercial or recreational purposes;

This seems to cover basically everywhere and every type of "area" or land unless not actually a city, town or settlement. So I guess a house or castle in the middle of nowhere is not a congested area. Maybe a field in the middle of nowhere is not (though fields are commercial). One interesting point though was the time frame. The idea that our office, on a Sunday morning, is not at that time being used substantially for commercial or industrial use as nobody is working in any of the offices. If that is a valid interpretation then we simply have to contend with the 50m rule for structures and vehicles not in our control. I also wonder what one has to do to justify "control" of a structure! If an adjacent office is empty can I just "take control" of it (i.e. have someone to watch out for any people approaching it and tell them we have a drone over head). So could I control all of the buildings within 50m of me as they are empty? This may mean my test flight at the office on a Sunday morning, and even over the road leading to the office, may have been 100% legit even with no PFAW. If so, cool, a place (and time) to practice.

The good news is the 150m of congested area goes down to 50m if you get a PFAW and possibly lower if you get one of the extended permissions.

Apparently, one of the other extended permissions is night flying. But I have failed to find any restriction on night flying in the legislation, so I may ask that one tomorrow. Maybe some of these restrictions are included in the basic PFAW as caveats and hence why one needs extended permission for such.

But it all makes no sense - what the hell makes a drone with a camera unsafe around people, vehicles, structures, congested areas, but a drone without a camera is not inherently unsafe around such things and so not needing of such restrictions?

One idea for practice was to put a lens cap or tape over camera on Phantom 4. I would argue that as equipped, at that point, it is not capable of surveillance and so not subject to 167. Not an argument to have with a judge maybe, but not a bad argument I feel. That would allow me to practice in my back garden then as clause 167 would not apply.

Overall it is not a good mix of pedant, techie, and the law, one way or another.

It is shitty wording and shitty legislation, clearly. The good news is that the FAA (US Federal Aviation Authority) are relaxing rules and the EU are expected to make rules that will replace the UK rules next year. Hopefully these new rules will at least be sensibly drafted and hence much clearer.

There was one other useful (and cost saving) point. The PFAW is something the company obtains, having produced an operational manual. It can then engage any pilot that has passed the theory and practical tests. This is slightly odd as part of the practical test is confirming we can follow the operational manual, when in theory we may not know who we are going to work for an what operational manual they will have! It is also the company that gets the commercial drone insurance. Given we are training two pilots, this does save some money.


  1. > "The reason it is hard is the vagueness, and stupidity, of the laws around this whole area."

    I like the way in which you added "around this whole area" here, as if all other laws are clear and sensible!

  2. I urge caution re this point:
    'there is not even a height restriction or any need to obey controlled airspace! It is sensible as a courtesy to notify ATC (Air Traffic Control) but not a requirement. '

    A PFAW operate sent this to our ATC unit.

    I am just writing to inform you that this Saturday my team and I are planning to undertake a series of short unmanned aerial system flights (flying a hexacopter multi-rotor/hexacopter) within your ATZ. The location of the flights will be in and around the fields of x (about 2km north of your aerodrome) between 09:00 and 17:00.
    We are a CAA approved operator. We will not fly beyond 500m from the co-ordinates given or any higher than 400ft.

    Please let us know if you have any concerns or would like to discuss the operation further.

    Many thanks,

    Name removed

    Operations Manager & sUAS Pilot

    ATC replied

    Dear Mr ..

    I see from your email sent to the x ATC Unit that you propose to operate an unmanned aerial system at a location within the x ATZ. The Air Navigation Order requires that you obtain permission from ATC to fly within an ATZ not merely notify us that you intend to operate.

    If I understand the location correctly the land there is somewhat higher than the Aerodrome and you intend to operate up to 400ft AGL. The proposed location, as shown on the attached diagram, is in line with Runway x and aircraft overfly that location between 350ft AAL and 500ft AAL. I am unable to approve autonomous operations at that location due to the potential conflict with our traffic (Article 127 Air Navigation Order). Please also that the ATZ is notified as active H24. Permission to operate within the ATZ will not be given unless we agree visibility and cloudbase limits and on site contact details together with a flying programme.

    Also an interesting point re 167

    The provision of images or other data solely for the use of controlling or monitoring the aircraft is not considered to be applicable to the meaning of ‘Surveillance or Data Acquisition’ covered at ANO 2009 167 for SUSA.”,

    If you have a spotter and dont record the flight and fly based on the video downlink 167 doesn't apply.


    1. Interesting. 166/167 are clear that you do not need permission and article 127 relates to gliders! They are als not asking for autonomous operations which is what he says he cannot approve. There is a general requirement to avoid other aircraft (which works both ways) and be safe but that reply makes no sense and I suspect the air traffic control are confused. The information on the runway and heights are a factor for safe flying which is useful, but again not an approval matter AFAIK. We were earned about that on the course.

    2. Oh, assuming he was under 7kg, which a hexacopter might not be.

    3. I will see the senior controller tomorrow and will ask.

    4. Cool. The original email did not say it was sub 7kg, which matters.

  3. Article 127 is from the ANO 2000

    The CAA refer to 127 themselves in CAP722

    Exemption from Order

    127 The CAA may exempt from any of the provisions of this Order (other than articles 75, 77, 82, 113, 114, 115, 116 or 128 thereof) or any regulations made thereunder, any aircraft or persons or classes of aircraft or persons, either absolutely or subject to such conditions as it thinks fit.

    1. ANO 2000 was revoked by ANO 2005. ANO 2005 was revoked by ANO 2009. I find no reference to "127" in CAP722 6th edition. Even so, an exemption under 127 ANO 2000 (or 242 of ANO 2009) would mean that the aircraft was exempt from a condition such as notification to ATC, so I don't understand the reference to 127 in this context. Basically the reply is wrong in quoting a twice revoked ANO, and wrong to mention autonomous flight, and wrong in talking of exemptions issued by CAA, and wrong that they have to approve such flights (if under 7kg).

    2. Just to add, obviously, that operating safety and avoiding other aircraft, is, of course still applicable. So in line with runway is going to mean having to stay low to comply with that, but "permission" is not needed for sub 7kg, that is clear.

    3. I would say "trust me, I am a pilot" but I have yet to pass my practical :-)

    4. :-)
      I have a PPL(A) IMC & FISO but under 7kg I shall bow to satco


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