Primarily for general aviation discussion, but other aviation topics are also welcome.
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User avatar
By PaulSS
#1655615
@Flyin'Dutch' What I was referring to is that transponders need to be interrogated, they don't just sit there and shout all the time. Mode S is even less likely to be shouting as the interrogation is selective. So, the metaphor of answering everyone in the room is incorrect, since not everyone is asking and some can't listen to the answer anyway.
#1655652
Flyin'Dutch' wrote:PAW may have hoped to flood the market and become a de facto 'standard' but that was never likely to happen.


Hmm interesting phrase ...

https://en.wikipedia.org/wiki/De_facto_standard
The term de facto standard is used in contrast with obligatory standards (also known as "de jure standards"); or to express the dominant voluntary standard, when there is more than one standard available for the same use.

Do you remember the published results of the conspicuity survey by the CAA, which we had asked the results to be published after 1 year
viewtopic.php?f=1&t=110220&start=30#p1649466

Through the use of the freedom of information act, we were able to obtain the raw data from the CAA. The raw data contains far more detailed and definitive information than the 'selective' data presented in the report

Even looking at this spot analysis at the beginning of 2018
This data will make pleasant reading for some, and uncomfortable reading for others

I can tell you that after almost one year on from the information published in this report, we can happily report that we see no lapse in take-up from the flying community throughout the UK and Europe
With respect to the relevance of the data, PilotAware had only started shipping 20 months before the survey.

Oh and by the way, for the avoidance of doubt - I have found it to be very pleasant reading

Finally the phrase 'flood the market' implies insincerity in our purpose, whereas people who know us, know that this is not the case - that being said, you may want to check out ebay for a pair of waders

Thx
Lee
Last edited by leemoore1966 on Wed Dec 05, 2018 4:29 pm, edited 1 time in total.
PaulSS, Ian Melville, kanga and 1 others liked this
User avatar
By ls8pilot
#1655725
leemoore1966 wrote:....
Through the use of the freedom of information act, we were able to obtain the raw data from the CAA. The raw data contains far more detailed and definitive information than the 'selective' data presented in the report

Even looking at this spot analysis at the beginning of 2018
This data will make pleasant reading for some, and uncomfortable reading for others

....
Lee


Sounds interesting - is there somewhere we could see the analysis of the full data ?
User avatar
By gaznav
#1655746
Anyway, back to the spectrum debate.

PaulSS wrote:
The phase out of Mode 3/A which is effectively answering everyone in the room when someone asks a question is a good example!


It doesn't, though. It only answers the person who asks a question. The answer can be seen by some others in the room but not everybody hears the answer.

Of course, from you there's mute response as you didn't hear the question and can't answer :wink:


Not quite, if the room is the interrogator’s swept volume then it is very much going to elicit a shouty response from every single Mode 3/A in that room. Then if you have 2 ‘rooms’ overlapping (ie. 2+ SSR interrogators sweeping the same area) then unless they interrogate at exactly the same time then you get all those ‘shouty’ responses. Then add TCAS/ACAS which is like a high power torch beam being shone in those rooms and every time someone is seen with that torch you get another shouty repsonse, then you can then understand why Mode 3/A can quickly swamp 1090 with a high traffic density. Then there is IDENT which shouts out another reply without an interrogation that also adds to the congestion - indeed if every single aircraft in the UK FIR pushed IDENT all at the same time then there would be all kinds of mayhem with FRUIT and garbling. Luckily, no one is that stupid.

That is why Mode 3/A is being phased out in Europe (and has been for quite a few years), that is why the UK came within an ace of mandating Mode S and why the US has had to adopt 978 for their GA ADS-B.
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User avatar
By gaznav
#1655753
Here is a good read on the use of lower power transponders in Europe by EUROCONTROL back in 2007: https://www.eurocontrol.int/sites/default/files/publication/files/surveillance-considerations-for-low-power-ssr-mode-s-transponder-operations.20071024.pdf

Here is the killer line with my bold added:

...it is not possible for States to achieve full technical interoperability of all aircraft with SSR-basd safety nets and ATC surveillance systems. Moreover, for many operators of light aircraft there is no suitable means of compliance with which to voluntarily equip their aircraft to access mandatory SSR or SSR Mode-S transponder carriage airspace. However, it is considered that in many cases, the existing limitations could be overcome by the availability of a small, pressure-altitude reporting Low-Power SSR Mode-S Transponder (LPST). Such an LPST would have to provide a defined set of SSR Mode-S Level 2es transponder functionalities in order to provide optimum inter-system interoperability whilst having the minimum effect on radio spectrum usage and mutual interference.


So EUROCONTROL seem to think low power is the answer, the CAA developed this into CAP1391, NATS joined in with Project EVA and uAvionix are so far the only company to have built a device that realises that vision. I wish more would do so as I really do think this is the way forward and I do not buy into ‘Project Fear’ that 1090 will collapse under the weight of use by such low power devices. I also wish that the CAA would revise their statement on ADS-B in that it should be ‘ideally used through transponders’ for GA as it really does not need to be for the reasons I offer.
Flyin'Dutch', Nick liked this
User avatar
By neilmurg
#1655760
leemoore1966 wrote:Do you remember the published results of the conspicuity survey by the CAA, which we had asked the results to be published after 1 year
viewtopic.php?f=1&t=110220&start=30#p1649466

Through the use of the freedom of information act, we were able to obtain the raw data from the CAA. The raw data contains far more detailed and definitive information than the 'selective' data presented in the report

Even looking at this spot analysis at the beginning of 2018
This data will make pleasant reading for some, and uncomfortable reading for others

I can tell you that after almost one year on from the information published in this report, we can happily report that we see no lapse in take-up from the flying community throughout the UK and Europe
With respect to the relevance of the data, PilotAware had only started shipping 20 months before the survey.

Oh and by the way, for the avoidance of doubt - I have found it to be very pleasant reading

Finally the phrase 'flood the market' implies insincerity in our purpose, whereas people who know us, know that this is not the case - that being said, you may want to check out ebay for a pair of waders

Thx
Lee
So what's a simplified take-away from that data?
It looks, on the face of it, that there's twice as much Pilotaware in the GA fleet vs ModeS/ES/ADS-B, and ten times as much Pilotaware as FLARM. In that particular (large) sample. And PAw was relatively new.

That's pretty important information for those considering an EC solution while waiting for ADS-B or its successor (or Pilotaware) to become ubiquitous. Even if the numbers are only 1/4 as favourable in the general GA fleet (the ones that fly), that's hugely significant.
User avatar
By mo0g
#1655762
neilmurg wrote:So what's a simplified take-away from that data?
It looks, on the face of it, that there's twice as much Pilotaware in the GA fleet vs ModeS/ES/ADS-B, and ten times as much Pilotaware as FLARM. In that particular (large) sample. And PAw was relatively new.

That's pretty important information for those considering an EC solution while waiting for ADS-B or its successor (or Pilotaware) to become ubiquitous. Even if the numbers are only 1/4 as favourable in the general GA fleet (the ones that fly), that's hugely significant.


I think the take-away might be that PAW was already the "de facto standard" that Flyin'Dutch was accusing PAW of trying to be.
User avatar
By Dave W
FLYER Club Member  FLYER Club Member
#1655766
Doesn't seem to align with the proportion of powered GA fitted with FLARM claimed elsewhere on these forums, quoting FLARM themselves ("fahsends of 'em"), does it?
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User avatar
By gaznav
#1655774
Dave W wrote:Doesn't seem to align with the proportion of powered GA fitted with FLARM claimed elsewhere on these forums, quoting FLARM themselves ("fahsends of 'em"), does it?


No it doesn’t. You only need to look at the Open Glider Network to see how many FLARMs are airborne when there are exceptional soaring conditions in the UK. Someone is either being economical with the truth or exaggerating the actual uptake numbers for their own gain...

Anyway, back to the meat of this thread. I now have all the software, licences and wherewithal to trial a SkyEcho 2 with some Classic FLARM. I just need a bit of weather and time off work to test it. :thumleft:
Flyin'Dutch', Nick liked this
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