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By Dave W
FLYER Club Member  FLYER Club Member
#1845104
(TL;DR: If you think there is a case for insisting under force of law that GA owners and operators must spend money on EC at the expense of other safety-related items, then please make it - logically, objectively and in suitable detail, here. I suggest that to justify any mandate, it is only fair that such a case is made to the GA community in advance.)

Yes, yes - another (yet another) EC thread. :evil: :wink:

But this one is intended specifically to break out and consider the pros and cons of mandating EC.

There are lots of other threads for the technical details and comparing one solution with another etc - that's not what I hope for us to discuss here.

All over social media, including these forums, I see people frequently calling for the CAA to mandate electronic conspicuity.

But I’m not (yet?) convinced that that an objective case for mandation has been made, and I’ll tell you why.

But first, let’s get some basics of my own position out of the way:

  • By “electronic conspicuity”, I don’t mean just Mode C/S transponders – even though that is also EC of course; here I am using the term as most others appear to mean it when they talk about "mandating EC": That is, EC = ADS-B/Mode S-ES/FLARM/PilotAware etc.
  • I am a fan of EC; I own both PilotAware and SkyEcho2 (and a Mode S transponder).
  • I think it is a Very Good Thing that the take up of EC is increasing and is as significant as it is.
  • The technology potentially delivers extras such as live in-flight weather and other useful data in the cockpit. That’s evidently also A Good Thing.

So hang on… If I think that, then why am I not convinced of a case for mandation?

Well:

  • Because “Mandated” also inevitably means in practice “Being forced to carry and maintain under penalty of law" and also perhaps “Being constrained from what can currently be done”.
  • Because there does not appear to be any (openly provided) justification made for it other than “Mid-air collisions: Scary” and “That seems like a good idea”
  • Because there is no published cost:benefit analysis on the need for mandating EC.
  • Because an effective implementation is likely not as straightforward as some appear to think.
  • Because it inevitably won’t be “just £250” to comply.

To consider those items in a little more detail:

JUSTIFICATION
If something is to be mandated (that is, people are forced to pay and/or lose existing capability, then to my mind in a democracy there needs to be a firm and objective justification for it, based on logic and not emotion.

There needs IMV to be an underpinning clear cost:benefit analysis that shows that the expense and any associated reduction in entitlements that may arise are worthwhile when considered in the round.

Which brings me to…

OPPORTUNITY COSTS
All of us have a limited flying budget (even you, Richard Branson). Spending money on one thing always means we can’t spend those funds on something else. Requiring people to spend money on EC addresses the mid-air collision (MAC) hazard, sure - but at the potential expense of other threats to GA safety.

The top 10 causes of light aircraft fatalities has been consistent for a few decades, and mid-air collision is quite a way down the list at number 8, typically representing 2-3% of all fatal accidents.

Money spent on EC is money NOT spent on AVGAS, training, upskilling etc. Given that the top two killers are Controlled Flight Into Terrain (CFIT) and Loss of Control In-Flight (LOC-I), there is – I suggest – quite a strong argument that experience, currency and recency are more cost-effective things to spend money on than a piece of electronic wizardry however good it may be in its niche.

And an installation may not be THAT good, which brings me to…

EFFECTIVE IMPLEMENTATION
There has been a lot of useful data and discussion recently on the effectiveness of the various options – including from the most helpful PilotAware VECTOR analysis tool and the limited FLYER qualitative assessment (in which I took part), later reported in the Dec 2020 magazine and a YouTube Video.

There is quite a lot to discuss from those data and analyses (see multiple other threads), but there are a couple of things that are evident: Carry-on equipment does suffer from obscuration (both transmit and receive); that the most effective installations have external antennas; an alert is only useful if it seen/heard.

In short, not all EC solutions are equal, and even identical equipment can perform quite differently depending on how it is installed.

The other very clear point is that simply having detection of others’ EC is not sufficient for an effective mid-air collision avoidance solution: You must also have a commanding ALERTING element to the installation, and that demands audio and sightline considerations to be taken into account.

Unless your installation provides you with a timely warning that you are able to assimilate then some implementations arguably may as well not be carried. (Is a tablet on your knee, with a late warning due to an internally obscured antenna and no means of immediately attracting your attention truly going to protect you?

So the above prompts the question: What, exactly, do those who call for it expect to be mandated?

An SE2 suckered to a side window, or a system with external antenna, eyeline display and plumbed into the intercom, or something in-between?

If something in-between, then what exactly?

What, if any, are the liabilities to ourselves - and the mandating authority, of course - associated with a less than perfect implementation?

My point being: This argument is not as simple as ‘Do you agree with the statement “The CAA must mandate carriage of EC?”’ – the devil as ever will be in the detail, and the detail is almost certainly going to push costs up, not down.

LIKELY ACTUAL COST
Who knows, until the issues above have been thrashed out? But are we really sure what is being asked for, or is the assumption simply “£300-£500 for a Rosetta or SkyEcho2, and jobzaguddun”?

I strongly suspect that a considered mandate will end up with rather greater costs than that. And perhaps it should - if something is to be mandated, then maybe mandate the installation as well as the baseline kit.

If I’m right (that costs will be higher than the few hundred sometimes assumed), does that change anybody’s opinion, especially given the more prevalent risks that don’t get mitigated by EC as discussed earlier?

AN ASIDE:
It seems that the conversation for most GA pilots – and also in the first part of this post - is currently based around air-to-air traffic awareness.

However, there is an undercurrent I detect from some areas that “it” (whatever it means – see above) is attractive to air traffic providers too.

And I can see the sense in that attraction – it’s likely to be much cheaper for them to move to an ADS-B reception network than it is for the current costly legacy infrastructure of primary and secondary radars to be maintained into the medium/long term. It may even be that moving away from legacy infrastructure allows the potential for more widespread use of other functions only available from ADS-B and UAT.

It is also likely to be the case that mandated EC supports the introduction of UAS (“drones”) into Class G.

Well, that’s great - both of those things: But if those are to be part of any case for mandation, then let’s be honest about it up front.

After all, what the ANSPs and UAS companies are effectively doing is moving their own costs onto the aircraft operators – so let’s have a conversation about whether everybody agree that the shift is equitable. We might agree that it is – given the potential for greater operating freedoms and functionality - but lets have an open and honest conversation about it, please.

That conversation should include how that potential will be actualised for all users, including GA – and should include what - if any – antenna performance limits are required (i.e. what, if any, obscuration is acceptable).

CONCLUSION
So, that’s my thinking. Please do disagree.

If you do, then here’s a challenge: If you believe there is a UK relevant basis for mandating EC that is detailed and convincing then please make it here.

I am willing to be convinced by a strong argument: I just haven't heard it yet.

I believe that if it is to be mandated, then it is only reasonable that a strong argument is publicly made first.

If you have an ANSP or Regulatory background, and are able to do so under your employers’ media policies, then it would be valuable to share thinking here too. But I’d be grateful if any hint of “I could tell you but I’m not allowed but trust me, there are good reasons” can be avoided – the whole point of this OP is that I want us to be able to hear and assess those reasons.

(Please note: Again, the question is explicitly about MANDATING it, not "Is EC a good idea” – I suspect we can all agree on that one. The question is about demanding people pay for it, rather than leaving it to them to make a choice.)

AFTERWORD
At some point somebody will inevitably make a comment along the lines of“Pilots being unwilling to spend £250 on EC – that’s only an hour or so’s flying”.
Let’s deal with that now: It’s a strawman fallacy. Firstly, many of us manage to fly for £30-£40 an hour variable cost. If you have to use cherry-picked data to make your case, then your case is unlikely to be strong; Secondly, it won’t be £250 since that assumes the soon-to-expire CAA subsidy and likely disregards some of the performance issues potentially required to be addressed in a mandated solution.

Also, I fully expect someone to comment along the lines of "If it saves one life, it's worth it". That's a great soundbite and I do sympathise with it having lost people I know to MAC. But I have also lost them to LOC-I and CFIT over the years. My view is that if we must choose (and realistically/unfortunately we must: Opportunity Costs) then I will tend to recommend mitigating the more prevalent hazards first.
ChampChump, Shoestring Flyer, Marvin and 19 others liked this
#1845113
@Dave W a gréât post and I’m certainly interested in how this develops.

May I add that I think there are three areas to be considered.

1. Basic Electronic Conspicuity that allows me to see you and you to see me in open airspace and provide the opportunity for us to avoid each other. The only defining principle is that it uses compatibility between systems. There is no mandate to carry as it’s purely for outside controlled airspace and provides no special privileges or access to other areas apart from it “may” offer improved situational awareness for uncontrolled areas.

2. The next level is for those wanting more from the EC simply situational awareness such as defined services, protection in areas of BVLOS, controlled airspace or even some kind of FIS service based on flight following. This will come at a prices as I think we are now in the realms of needing devices with known performance and probability of detection. That is an area that would some kind of mandate but offer in return access to areas that currently may be restricted unless you have access to radar services or devices emitting positional information that meets a defined standard and hence mandate.

3. Access to add on services such as inflight weather, NOTAM etc to a defined standard that means the data can be received and trusted. That means defined kit with standards, I suggest ICAO standards so the big boys can get involved, and will cost and provide the confidence to access areas NOTAMEd as active/not active at short notice.
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By johnm
FLYER Club Member  FLYER Club Member
#1845116
IMHO the issue revolves around the introduction of UAS. There is serious pressure to let UAS loose and that means Class G co-existence. So as a long term systems designer this would be my take:

Let's start by being clear about the requirements and that means a good deal of discussion about how UAS will be deployed and the implications of the different scales and capabilities and usage of UAS.

Once we understand the requirements we can start looking at how those requirements might be satisfied and what the costs, risks, constraints and opportunities look like.

At that point we face the practicalities and what those look like we can't determine at this point.

One of the things that we have seen from the B word is the traditional systems engineering process being reversed, so instead of design, test and implement we're in the middle of an iterative implement, test and design cycle. We really don't want that to happen with UAS in class G thank you!
bogopper, JAFO, Hollman liked this
#1845117
We’ve had this debate before Dave - but surely you can see the cost of EC vs cost of flying more because of loss of control comparisons are rubbish. MAC is a well known risk, which includes third parties and has credible event severe outcomes, and has known workable and effective mitigations. The other is entirely subjective.

GA wants to operate in a collaborative environment. If you want access to that environment on current terms, you may have to accept a direct cost (tariff if you want) for that access. You can do as many cost benefit analysis as you like for your GA aircraft but unless you are considering the entire ecosystem and every opportunity and cost the analysis will be worthless. If GA doesn’t want to pay a nominal cost (and it is nominal despite all the wailing from many) to cooperate in the environment, well fine but you can then expect to have restraints put on your operation.

I have to pay for an MOT on my cars each year. The cost benefit to me is rubbish because I pay to have them dealer serviced and maintained, and do my own maintenance checks so the MOT is a useless cost additional to the service. I never get a failure or anything I don’t know about. I would rather spend the money on an advanced driving lesson each year. However to operate on the public environment roads it is a cost I have to bear for that access because society deems it is the right thing to do.

Society is rapidly deeming EC is the right thing to do. Speak to any general member of the public and they would think a GA pilot dragging their heels to fit it is mad; a coroner may have more stringent views.

(Personal opinion) it’s now time to stop trying to appease the whole church of people and get on with a mandate to smash home the cultural and technological change. More studies, analysis and other guff is just delaying tactics.
rdfb, gaznav liked this
#1845122
"Please do disagree."
Difficult to disagree when I agree totally with the entire post.
Well done - a super summary.

Supplementary points:
- I think it is all about drones and their acceptability to the public - the perception of risk of collision is what matters. No one will care two hoots about us arguing that MAC is not the biggest killer of GA flyers when they believe that drones can't see light aircraft.
- Many flying machines will find it hard to carry and provide power for anything more than a SkyEcho (small, self contained, self powered). I'm thinking about sailplanes, paragliders and paramotors, vintage aircraft and so on. Mandating much more will cause real difficulty. There is need for further technical innovation and development.
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By Cub
FLYER Club Member  FLYER Club Member
#1845123
I think we are a long way off both the necessity and justification for mandatory EC in the U.K for the following reasons;

The management of the mid-air collision risk in pure Class G airspace is primarily managed via ‘see and avoid’. So long as retain relatively large volumes of that basic ICAO classification then the decision to deploy and additional safety net when operating within in it should rest with the pilot.

The sense and avoid technology to necessitate 100% EC equipage in order to accommodate a reliant platform such as BVLOS drones is simply, not yet proven. In some cases those concepts are just months away from confirmation or modification but even if that operating environment is proven as safe and robust, we are a long way from the necessity of accommodating that collaborative environment throughout our entire airspace structure..

However, if we are going to drag our airspace structure and management into the second quarter of the 21st century, we do need to see widespread voluntary uptake of additional electronic safety nets. I suggest the following areas;

The use of Class E airspace and combined TMZ to support low intensity, low complexity IFR operations. These TMZs are likely to require equipage with a full power transponder and not standalone ADS-B devices because of the necessity to enable the ACAS safety net in airspace where VFR flight is uncontrolled/separated from IFR. A significant proportion of our existing Class A and D structures could be reclassified to Class E with TMZ in my opinion, but this must be done in conjunction with the simplification of airspace structures and volumes because Controllers managing IFR traffic within Class E airspace do need to room to discharge their obligations with regard to separation.

It is almost certain that if we really want to safely accommodate BVLOS drone operations in Class G airspace then we will need a collaborative EC environment. I do passionately believe that integration is what we need rather than segregation if we are to retain GA and sport aviation’s freedom to roam in Class G.
Once the trials and safety cases have been proven to show that interoperability can be safely achieved in a collaborative EC environment, we must work out a method for the minimum size and time of deployment of this mandate. I am thinking of properly notified and disseminated ‘pop up’ ADS-B mandatory TMZs with alternative access arrangements.

Once we have that establishment and disestablishment of short notice equipage mandates hacked, we must take advantage of that flexibility in use of airspace to switch on and off other suitable volumes such as runway dependent CTAS, glider soaring areas, dedicated aerobatic areas etc.

We must utilise the availability of good quality of good quality, affordable surveillance data by non ATCOs to achieve additional safety benefit in appropriate scenarios within Class G. GNSS approaches supported by a mandated EC environment and the sharing of traffic information with participating IFR traffic is all that is safely required to replace the almost unachievable Article 183 or a restrictive set of conditions as an alternative.

ATZs should be replaced by a TMZ (ADS-B) of suitable dimensions at locations which due to their traffic density or complexity will benefit from such a mandate. However, non-equipped access along the lines of compulsory annunciation on entry/exit and circuit calls must be included. The necessity of anybody on the radio at these locations should be significantly reduced to those locations that will significantly benefit from the operator having access to surveillance data and the relay of such information. Probably, only at the busiest GA locations or busy GNSS approaches accommodating multiple IFR traffic.

I will stop there for the moment and let some others get a word in edgeways. It is a subject I am very passionate about.
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#1845124
While I am a great fan of EC, I find it hard to justify mandating it, especially when there is are such widely different views on the technology available.

My view is that to get adoption you need to make EC kit attractive for some other purpose - Flarm took off in the gliding community partly because the Flarm devices were firstly certified as IGC Loggers (so usable for sporting purposes to verify flights), then became integrated with other kit such as Nav Computers. Much more easy to cost justify when you are looking at spending "X" on a logger/nav computer etc anyway, or "X+20%" to include EC (although Flarm has become rather more costly of late!)

My guess is EC will become attractive if/when any of the following happen:

1. It is in common use by ATC in and around GA ATZ's, simplifying your interaction with these units
2. It enables you to easily transit certain blocks of airspace - maybe "Drone Zones" (whatever they end up being) or "TMZ+".
3. It becomes integrated with other equipment such that it is an easy add-on.

I think an inhibitor at the moment is the lack of clarity on protocols and technology - we do not have a common standard, or even a common view (for example on ground-relay of data). Also we do not have a "mature" market (maybe with the exception of Flarm kit), by which I mean lots of choice in vendors, form factor, price range, displays & warning devices.

As an aside, while SE2 may not be the final product, think this type of approach is far superior to Mode S, which is basically 1950's technology; I don't want to be sitting on a 200W+ transmitter, nor do I want to have to double my battery capacity just to get 50% of the EC job done!
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By James Chan
FLYER Club Member  FLYER Club Member
#1845128
Well, this is where ADS-B is mandated in the USA today: https://www.faa.gov/nextgen/equipadsb/r ... /airspace/

Over here, if mandating EC in busier areas means I can get better access to airspace whilst improving my situational awareness, then the few hundred £££s as shared amongst in the group will be a small cost compared to the fuel savings and safety benefits that will be realised over the years.

Like RMZ and TMZs today, there should be special procedures provided at the controller's discretion for those not equipped. But I think in this coming decade, those that refuse to equip may find themselves increasingly confined to quieter and remote places such as Cornwall.
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By Dave W
FLYER Club Member  FLYER Club Member
#1845130
@MattL forgive me but you have jumped straight to an assumed solution. You have not made a case as I hoped, you have made assertions.

My hope in this thread is for a case to be made, in which event assertions are not required as the logic makes assertions moot.

As it happens, the main trigger for the post was that I frequently see GA pilots - lots of them, it seems - themselves calling for mandating EC in order to mitigate the MAC hazard. I do not believe the majority of them have fully thought the issues through, and I do feel that without objective and reasoned challenge there is the potential for their viewpoint to be taken as tacit support for mandation by the CAA.

Mandatory EC is a solution - make the case why it is the solution. And describe what it means in practice.

One could equally - and equally unhelpfully - say that the solution for "drones" instead is carry on non-cooperative (ie target not emitting) sense and avoid for UAS. What's the next mandate for everybody? LIDAR? (Exaggerating for effect)

This current situation appears to be reactive and technology-driven, with little to no consideration of whether an acceptable outcome could be achieved in another way. That's not right, to my mind.
IMV there needs to be a proper discussion, consideration of options, balance of impact, consideration of where costs should lie and then mandate something. But that's not what appears to be happening - the discussion etc is short-circuited and we are presented with a "take it or leave it" attitude.

There are other ways - discussion, explanation and making a convincing case for example.

I have had an off-forum message along the lines that there is no CAA thinking around a blanket mandate, rather the creation of ADS-B Mandatory Zones (AMZs).

OK, perhaps - but again, where is the case for the creation of those? How might they grow?

Maybe there is a supportable case, equitable for all on balance, and maybe there isn't - but we've not had it shared if there is, and so we cannot tell what it is.

For example, a reasonable question to ask is that there already TMZs (which IIRC arrived themselves as an un-consulted concept so far as GA was concerned!) so what does an AMZ demand that a TMZ could not deliver? But no, what happened appears to be that the suggestion of AMZs has arisen almost as a fait accompli, and no consultation on the concept (and I mean the concept, not an individual implementation) was identified first. What happens if I enter an AMZ but my SE2 becomes obscured - is that going to be treated as an airspace incursion? It's not black & white, and there are legitimate unaddressed concerns.

It is a creeping change, which could well grow rapidly, and I think (again) it needs justifying.

Who is to tell us that a few isolated AMZs tomorrow does not becomes the norm in a few years and that without an acceptable EC solution (and it seems evident that Mode S is not going to be acceptable) we won't be allowed in.

The attitude that "well, this is the solution we have decided without consultation, so this is what you need to do" is not, IMV, reasonable any longer without explanation and due process. Otherwise we might begin to think that GA once again just gets what it is given and lumps it.

"Best place in the World for GA" remember? Part of achieving that is listening to the GA voice in an equitable fashion to everybody else's - not telling us what we must do/think/pay for without consultation or public justification.

@James Chan, you have expressed an opinion relevant to yourself rather than considering anybody else's perspective. That's just my point and a problem that concerns me - it is not objective.
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By James Chan
FLYER Club Member  FLYER Club Member
#1845140
you have expressed an opinion relevant to yourself rather than considering anybody else's perspective. That's just my point and a problem that concerns me - it is not objective.


I considered the people who I have flown with or known and they have shared a similar view.

But if you're looking for objective evidence, I sort of assumed the FAA did a huge amount of research and innovation into EC which led to their NextGen airspace. And their equivalents over here perhaps did something similar and/or borrowed these ideas. I actually don't know the source of these research papers, but I had entrusted them to be somewhat intelligent in their decision making in shaping future airspace given the data they have available to them such as radar data, service provision, airproxes, MACs, and other occurrences and factors.

Perhaps I had been a bit too optimistic here. Many have jumped onto the "EC is cool" bandwagon, but of course I would not want a mindless repeat of the mode-C to mode-S transponder equipage that comes at cost but offers little benefit to the average GA user.
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By Cub
FLYER Club Member  FLYER Club Member
#1845143
I think we should be clear on the terminology., the CAA agreed with EASA just before the split that regardless of the equipage mandate, the volume will be referred to as a TMZ. It will been down to the airspace change applicant to determine the equipage mandate that they seek within the TMZ. You could therefore have a TMZ which has an ADS-B mandate, or a transponder with ADS-B requirement or potentially any other combination of EC.

Personally, I think we should push for TMZs to have an ADS-B requirement as a minimum because that will currently enable the most affordable access.

On a related note, I also think a positive move by the Regulator would be to require ADS=B Out to be enabled on all new Mode S transponder installations given the regulatory impact with regard to cost versus the interoperability opportunities with other concepts and technologies.
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#1845146
@Dave W I know we are conceptually opposed on this - to me, you are trying to apply systems engineering to a sociological problem. You won’t get the analysis or artefacts you desire. IMHO GA is going to get bulldozed off the tracks on this issue if we continue to faff around. We should be going to the regulator and saying ‘we’re up for this, we want to lead the field with our airspace colleagues, how do we make it work?’ not hand wringing about everything and opposing anything other than non radio open Class G for all.

Ps if anyone doesn’t believe the way this could go, look at the EV mandates of late

Pps it will be interesting to read the debate!
By johnm
FLYER Club Member  FLYER Club Member
#1845152
The anecdotal evidence is that EC has 2 roles to play. The first is making it possible for LARS to be abandoned entirely, the second to make it practicable for drones to be let loose.

If we start from the viewpoint that these are the basic requirements then we need solutions.

LARS becomes redundant essentially if we can all see each other and get info from ATIS/Volmet.

If drones are as unpredictable in their pathways as GA, then they have to be able to see and avoid so a drone equivalent to TCAS is needed and all GA will have to output something they can process.

There is a great deal of political and practical detail behind addressing this which a forum post is never going to cover adequately, but some serious and coherent discussion on airspace management, ATS and EC is needed if we're to have a joined up solution. Given recent history my money is on another dog's breakfast...
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By Pete L
FLYER Club Member  FLYER Club Member
#1845155
I disagree that LARS is redundant.

In terms of risk to life, GA is around 1 in 10^7 per hour and an airline passenger is around 1 in 10^9. CAT gets the benefit of both TCAS and ground surveillance.

Increased controlled airspace has increased GA risk particularly round the M25, although most of the collisions seem to have occured a bit further out. It is also not the case that the controlled airspace is fully used by CAT or that everything in it could be considered known traffic to the same standard as applied to GA incomers. Airspace redesign and the improvements in the approach to using and policing surfaces of equal risk - which is what the controlled airspace boundary really does - should be supported.

There's a reasonable case that the CAA could and should be prosecuted if there were another collision in an area where LARS were not available.

The CAA has an obligation to provide nationwide LARS which was never fully written into the NERL license - the one group of people with the physical capability to deliver it if not the corporate or union desire to do it with FISOs.

Back to EC.

It's clear we have two proprietary manufacturers and one new US entrant who is pushing an argument which would get least resistance from rest of the industry. Were this mobile phones and we were still in the EU there would be common standards and a patent pool.

If I had charge of the CAA I would be tempted to bang some heads so the manufacturers could compete on price and features but not on basic interoperability.

A final thought for now. Despite reservations from some quarters, it seems reasonably obvious that there is no real difference between a rebroadcast from an automated ground station and a controller saying something from looking at a display. They both work to standards. There is nothing therefore wrong in principle with everyone being conspicuous by their preferred means, the ground station makes a prediction, and says something either by data protocol or by voice.
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