Re: [Drip] ADSB

[Robert Moskowitz <[e-mail]>]

On 7/12/23 11:52, Alexandre Petrescu wrote:
>
>
> Le 12/07/2023 à 17:31, Robert Moskowitz a écrit :
>>
>>
>> On 7/12/23 11:13, Alexandre Petrescu wrote:
>>> thanks for the clarification I must have endeavoured in
>>> unchartered lands...
>>>
>>> Just to clarify: I am not disputing.
>>>
>>> I came with this thread to say that I saw ADS-B drones on flightradar.
>>
>> I am sure people do it.  How they get an aircraft number might be 
>> interesting.  Of course some transponders are preset for this from 
>> what I have heard.
>>
>> Also I am away of code that takes "standard" Remote ID messages and 
>> feeds that into ADS-B systems.  So you see them in things like 
>> FlightAware, but they are NOT sending ADS-B.
>
> Interesting.  If so then flightradar might say so somewhere on the
> Internet.

See my draft:

https://datatracker.ietf.org/doc/draft-moskowitz-drip-crowd-sourced-rid/

For harvesting RemoteID messages to feed into UTM.  Feeding into ATC is 
probably not a good thing, IMHO.

>
>> of course you have to lie about the aircraft number,
>
> For the aircraft type, registration and country of reg.: it says 'N/A'.
> (for 'Not Available' I suppose - never knew what a dash had to do there,
> as if it were 'Not/Available').
>
> There is no 'aircraft number' in the page, but maybe you meant something
> like that.
>
> Also, even the legally carrying ADS-B aircraft sometimes dont provide
> some of these ADS-B fields, or are some times badly read, or badly
> interpreted.
>
> But I am happy to see what is there to be seen.
>
>> going from the 20 character UA ID to the 24-bit aircraft number...
>
> The 'ADS-B' drone I saw on flightradar said the 'ICAO 24-bit address'
> was '511161' decimal I suppose.  Is there a means to check the validity
> of this number?  Or to tilt to thinking it is a fake?

I do not know if there is a way for the general public to link the 
24-bit address back to anything remotely interesting.   Just have not 
spent time in that direction.

>
>> The one effort I reviewed on this I asked this question, and they 
>> said the hashed the UA ID down to 24 bits...
>
> Sure, we can do anything, put random or other crazy things in there -
> but maybe it is not very good to play like that with these numbers.  But
> I will not dispute that either.  I am just happy I could see it there.
>
> If they hashed the UA ID to 24 bit for a 'standard' Remote ID of a drone
> into ADS-B - would they do the same for a ground vehicle at the airport?
>  Do ground vehicles at airport also likely carry 'standard' Remote IDs?
> (obviously ignoring vehicles have other IDs like VINs...)

WE would like to see Trustworthy Remote ID (DRIP work) used beyond UAS!  
I am working along these paths in ICAO.  Civil Aviation is pushing a 
PKI; FAA and EUROCONTROL are doing initial testing. Aircraft and other 
moving things that participate could easily have DETs to use.  WIP.

>
> Alex
>
>>
>>>
>>> That's about it.
>>>
>>> Alex
>>>
>>> Le 12/07/2023 à 16:56, Stu Card a écrit :
>>>> The UAS RID rules are _not_ defined in this WG!
>>>>
>>>> They are defined by Civil Aviation Authorities (CAAs) in each 
>>>> jurisdiction, with coordination via the International Civil 
>>>> Aviation Organization (ICAO).
>>>>
>>>> Disputing the rules should be taken up with them, not with the DRIP 
>>>> WG or any part of IETF.
>>>>
>>>> Such rules are mentioned in DRIP docs only as background: 
>>>> motivation, context & constraints.
>>>>
>>>> Standard Means of Compliance with UAS RID rules, in turn, is mostly 
>>>> the province of SDOs other than IETF, primarily ASTM International. 
>>>> Again, disputing those standards should be taken up with those 
>>>> SDOs, not us.
>>>>
>>>> Only if some reference, in DRIP docs, to the rules or external 
>>>> standards, is factually incorrect or unclear in expression for 
>>>> understanding by DRIP protocol implementors, is it something we 
>>>> should be debating here.
>>>>
>>>>
>>>> Get Outlook for Android <https://aka.ms/AAb9ysg>
>>>>
>>>> ------------------------------------------------------------------------ 
>>>>
>>>>
>>>>
>>>>
> *From:* Alexandre Petrescu <[e-mail]>
>>>> *Sent:* Wednesday, July 12, 2023, 10:43 *To:* Stu Card 
>>>> <[e-mail]>; Robert Moskowitz 
>>>> <[e-mail]>; Carsten Bormann <[e-mail]> *Cc:* 
>>>> [e-mail] <[e-mail]> *Subject:* Re: [Drip] ADSB
>>>>
>>>>
>>>>
>>>> Le 12/07/2023 à 16:00, Stu Card a écrit :
>>>>> Very short answers (all for which I have time):
>>>>>
>>>>> The rules for RID are based not primarily on RF
>>>>> considerations, but on aviation considerations.
>>>>
>>>> hmmm... it's a principle that is reasonable and that could be debated.
>>>>
>>>> One will excuse me for not knowing precisely what are the RID 
>>>> rules. The RID rules are defined in this WG and I will need to look 
>>>> at them.
>>>>
>>>> If I look at them, one day, I will look at them from this perspective:
>>>>
>>>> For example, when RID rules say 'altitude' they should say 
>>>> 'altitude expressed in meters and not in feet as is currently
>>>> the inherited case from WWII development of aviation'.
>>>>
>>>> This kind of text could be of enormous help to implementers:
>>>> they simply would need to call less functions(), because less
>>>> need of conversions.
>>>>
>>>> It is the same when RID rules say 'heading' or 'speed', or when we 
>>>> talk about airport track orientation.  It should be made easy to 
>>>> implementer to compare a heading value in a 'heading' of a
>>>> UAS to that of a track. One should come up with a single common
>>>> way of expressing track orientation, compatible to that of RID
>>>> rules, instead of several and incompatible, as is the case in
>>>> current air flight industry.  It is because if one does that 
>>>> (interoperable defs of headings) then the programmer has an easier 
>>>> task.
>>>>
>>>> Also, about RID rules: they should say that when ASTM wants to send 
>>>> position and heading they should send the NMEA statements, without 
>>>> conversion.
>>>>
>>>> Until then, if we can not do that, we can also have a human 
>>>> listening to the radio airport and maneouvering locally or from
>>>> a distance, using an innombrable number of calculators and 
>>>> conversions, after having learned tomes of manuals about how to fly 
>>>> things.  It is basically easier.
>>>>
>>>>>
>>>>> Crewed aircraft _mostly_ fly above 500 feet, except during takeoff 
>>>>> and landing.
>>>>
>>>> I always had problems with this term 'crewed' aircraft.  I noticed 
>>>> it also in the TVR WG, in its reverse form 'uncrewed' aircraft.
>>>>
>>>> But in reality there can be uncrewed crewed aircrafts too (Unmanned 
>>>> Air Mobility device, a flying taxi, does carry a
>>>> couple of persons on board - 'crew?', yet none of them actually
>>>> drives the UAM - they just signed the insurance agreement). An
>>>> uncrewed aircraft is still crewed by the fact that a (group of)
>>>> persons on the ground is its crew (drone Reaper is such). There
>>>> can also be these devices that are not crewed, are not
>>>> continuously driven from a ground by a crew, yet there are very
>>>> many eyes of people loooking at where it is going to - they're
>>>> pre-programmed.  These would be the true 'uncrew' aircraft even
>>>> though there are many crews simply looking at them.  They fly at
>>>> more altitudes than 500 feet.
>>>>
>>>> This is why I am not sure how to use this term 'crewed aircraft'.
>>>>
>>>> But I think you meant a 200 passenger aircraft like a regular 
>>>> airline flight from a city to another.  Even that can be automated 
>>>> (crewless?) soon.
>>>>
>>>>> Small uncrewed aircraft _mostly_ fly at much lower altitudes, as 
>>>>> they are flown largely not to get from one place to
>>>>> another, but for photographing or otherwise sensing things on
>>>>> the ground (or for recreation).
>>>>
>>>> BEcause of this term 'crew' I can not say whether I agree or not 
>>>> with you.
>>>>
>>>> Instinctively, I'd say that there are so many other flying aircraft 
>>>> that it is hard to say so easily at which altitudes are they 
>>>> allowed or not, simply based on that 'crewed' qualifier.
>>>>
>>>> I think the point of view of 'crewed' vs 'uncrewed' is limited in
>>>> itself, leading to potentially missing some aspects.
>>>>
>>>>> The FAA has established an upper limit of 400 feet AGL for small 
>>>>> uncrewed aircraft flying under their rule appropriate
>>>>> for most such, to provide 100 feet of vertical separation from 
>>>>> these small UAS and where the crewed aircraft _mostly_ fly.
>>>>
>>>> I will not oppose - maybe it is sufficient for them.
>>>>
>>>> If I were to be picky, I'd say that the notion of 'AGL' itself can 
>>>> be subject to debate (there are several sea levels in this world 
>>>> and moreover they change as we speak) and if one asks why then I 
>>>> reply that if one would like to put NMEA statements in ASTM 
>>>> messages for the goal of avoiding conversions then one
>>>> might be facing such aspects of precisely what is a sea level.
>>>>
>>>> But I will not go to the respective SDO, so I leave it there.  I 
>>>> agree they set limits where they need them.
>>>>
>>>>> WRT units: yes it is a mess; no the EU does not use precisely the 
>>>>> metric equivalents of feet etc. in their rules; note my original 
>>>>> message said "EU rules are similar" not "EU rules are the same 
>>>>> except for translation of metric units".
>>>>
>>>> I agree, you did not say that.
>>>>
>>>>> IETF does not get to write rules for aviation, therefore neither 
>>>>> does IETF get to write rules for aviation communications; we can 
>>>>> only provide technical standards for interoperable network 
>>>>> protocols that _enhance_ those communications.
>>>>
>>>> It's a good thing, because enhancing communications is always good.
>>>>
>>>> Alex
>>>>
>>>>>
>>>>> -----Original Message----- From: Alexandre Petrescu 
>>>>> <[e-mail]> Sent: Wednesday, July 12, 2023 9:45 
>>>>> AM To: Robert Moskowitz <[e-mail]>; Carsten 
>>>>> Bormann <[e-mail]> Cc: Stu Card <[e-mail]>; 
>>>>> [e-mail] Subject: Re: [Drip] ADSB
>>>>>
>>>>>
>>>>>
>>>>> Le 12/07/2023 à 13:56, Robert Moskowitz a écrit :
>>>>>>
>>>>>>
>>>>>> On 7/12/23 06:45, Carsten Bormann wrote:
>>>>>>> On 2023-07-12, at 11:52, Alexandre Petrescu 
>>>>>>> <[e-mail]> wrote:
>>>>>>>> why not 400m
>>>>>>> This is not a domain where we get to invent boundaries.
>>>>>>>
>>>>>>> (Also, generally speaking, of course we should have a strong 
>>>>>>> bias to using SI units, but in a domain where regulation is 
>>>>>>> widely based on furlongs per fortnight,
>>>>>>> we’ll have to adapt.)
>>>>>>
>>>>>> And anyway it would be 125M to be a bit more than the Imperial 400'.
>>>>>
>>>>> True.
>>>>>
>>>>> And it obviously begs the question whether in Europe they also 
>>>>> have the same limit of 400' equivalent in meters.  I strongly 
>>>>> doubt that an EU document would talk about a limit of
>>>>> precisely 121.92 meters just because of being converted to the
>>>>> easy to grasp 400 feet.
>>>>>
>>>>> At that point we talk about devices that might be different in an 
>>>>> EU market than in an US market.
>>>>>
>>>>> What is the EU altitude limit for numerous drone aircraft to
>>>>> be considered flying very low, so numerous and so low such as
>>>>> to be forbidden to carry ADS-B equipment (or turn it off at
>>>>> lower than that altitude if it carries one)?
>>>>>
>>>>>> Why 400'?
>>>>>>
>>>>>> I think it was to keep general aviation some reasonable distance 
>>>>>> above people on the ground.  As the ceiling for UA that is a 
>>>>>> consequence.
>>>>>
>>>>> You see, I think there is an error.
>>>>>
>>>>> 400 feet might be a good limit in terms of separation of
>>>>> people and objects above their heads, but it is certainly not
>>>>> any limit in terms of radio communication.
>>>>>
>>>>> If there is to be a radio communication limit (use or not use 
>>>>> ADS-B) it should be based on the power levels it uses and the 
>>>>> guarantees of range. In WiFi, bluetooth and 2G..5G that's how they 
>>>>> separate.
>>>>>
>>>>> For example, an 5G-carrying UAS would be limited to 450meter 
>>>>> altitude because that is how high the ground 5G oriented towards 
>>>>> ground reaches high.
>>>>>
>>>>> A bluetooth-carrying UAS (and not carrying ADS-B) would be limited 
>>>>> to 100 meter altitude because that is how high a bluetooth device 
>>>>> is allowed to emit, by bluetooth regulation.
>>>>>
>>>>>> "They can't go any lower, you can't go any higher."
>>>>>
>>>>> Strange.  Many devices, especially those who plane or glide like 
>>>>> these UAS drones, and helicopters too, will stay stable
>>>>> at very many low altitudes.  Their power systems - more and
>>>>> more performing, allows for that.
>>>>>
>>>>> I very well see a helicopter stable 100meter above the ground, and 
>>>>> surely it carries an ADS-B device, if not several of them.
>>>>>
>>>>>>
>>>>>> It is called boundaries to keep unequal players apart.
>>>>>>
>>>>>> One of the interesting debates in this is that the 400'
>>>>>> floor is to ground obstacles like radio towers.  Thus since
>>>>>> big birds have to stay 400' from that 700' radio tower down
>>>>>> the block, you can take your UA up to 1100' right next to
>>>>>> it... Or so some claim.
>>>>>
>>>>> Right!
>>>>>
>>>>> RAdio towers, or radio towers with even higher anti-flash 
>>>>> ('paratonnerre', fr.) on them?  That adds some 10 meter to the 
>>>>> picture, to which an UAS drone would need to pay attention, just 
>>>>> like helicopters need to care about power lines above ground too.
>>>>>
>>>>>>
>>>>>> And speaking of Imperial vs Metric...
>>>>>>
>>>>>> Civil aviation separation is 1000'.
>>>>>>
>>>>>> This has already caused incidents where a lesser  Metric distance 
>>>>>> was used by one aircraft against one using the greater separation 
>>>>>> of Imperial.
>>>>>>
>>>>>> Fun!
>>>>>>
>>>>>> Not.
>>>>>
>>>>> I agree.
>>>>>
>>>>> Alex
>>>>>
>>>>>>
>>>>>> Bob
>>>>>>
>>>>
>>>
>>
>> -- Standard Robert Moskowitz Owner HTT Consulting C:248-219-2059 
>> F:248-968-2824 E:[e-mail]
>>
>> There's no limit to what can be accomplished if it doesn't matter
>> who gets the credit
>

-- 
Standard Robert Moskowitz
Owner
HTT Consulting
C:248-219-2059
F:248-968-2824
E:[e-mail]

There's no limit to what can be accomplished if it doesn't matter who 
gets the credit