At a simple level the UK gets 1-2 midairs a year. And the US has about 5x the GA hours of all of Europe, IIRC. See the GA Decline thread; loads of data there. Of course most of Europe’s land area has almost zero GA.
So it looks like the UK (and prob99 France Germany and 1 or 2 other busy countries) is well ahead of the US in killing people 
The reasons are fairly obvious, I think. Start with almost nobody here flying above 3000ft – and this is supported by midair data, with the one exception of the famous 2x Grob collision at ~4000ft after which the RAF fitted all the Grobs with a TAS6xx TCAS1 and a SN3500 to display the data (nice work for Wigglyamp :)). But in the US you have basically 1200ft AGL to 17999ft as Class E so anybody who can read an altimeter is likely to just zoom up to something reasonable.
Silvaire wrote:
Fairly obviously, in a volume of air with a few airports all located on the ground, fixed and non-uniform physical geography, and fixed and non-uniform airspace structure aircraft do not move randomly through the volume or collide at random like helium atoms in a jar.
That’s not the point. The point is movement without the ability or knowledge to steer away from colliding objects (pure geometry). You cannot stop collisions unless:
Thus it is exactly like helium atoms in a jar (or bananas in outer space if that’s a better analogy for you).
I think you all are overthinking this by miles and miles. The reason why people collide is they haven’t seen each other. They behave like helium atoms quite literally, zooming ahead in perfect bliss and ignorance.
The only way to stop that, or at least reduce it substantially, is for people to start being aware of each other. Right now the only way appears to be ADS-B. Is it the right move? beats me, because we don’t yet know the side effects if everybody starts using it everywhere. There’s always a side effect.
About 80% of the US GA fleet has ADS-B Out. Except for above 10,000 MSL and Class C/B operations, aircraft without an electrical system are permitted. My home base is non towered and is inside the 30 NM Mode C veil and under a Class B shelf, probably has about 10 based aircraft without ADS-B Out or a transponder. We have about 200 aircraft based on the airport. Much fewer aircraft are equipped with ADS-B In other than via a portable. Portable ADS-B In is less than ideal for traffic purposes. I see a lot more traffic than I used to, but most is not a threat and I can’t visually locate a fellow GA aircraft much beyond 2 NM and rarely at 3 NM. So ADS-B has made one more aware of traffic, but not sure it makes much difference. Operation in the pattern is below TIS-B ability to point out of non ADS-B traffic with a mode C transponder. Outside the B/C areas, ADS-B and transponders are not mandated and that is where the majority of non equipped aircraft live, so flying into one of those airports, including those with towers, ADS-B leaves a lot out, particularly at lower altitudes such as in the pattern where most MAC occur.
NCYankee wrote:
Operation in the pattern is below TIS-B ability to point out of non ADS-B traffic with a mode C transponder. Outside the B/C areas, ADS-B and transponders are not mandated and that is where the majority of non equipped aircraft live, so flying into one of those airports, including those with towers, ADS-B leaves a lot out, particularly at lower altitudes such as in the pattern where most MAC occur.
While TIS-B-only (meaning Mode C or S only) traffic likely won’t been seen on ADS-B IN at traffic pattern altitudes, and there is an associated time delay anyway as you’re not receiving that data directly from the other aircraft, I don’t think as a practical matter ADS-B IN leaves out a lot of traffic if there’s Class B/C anywhere within say 50 miles of where you are, because almost nobody will likely be TIS-B only or negative transponder. My airport of 600 planes or so has maybe two (2) non-electrical planes that aren’t equipped, a J-3 and a Taylorcraft DCO. This situation is true at most of the very busy airports to which I personally fly, regardless of whether they are in Rule airspace. Outside of those areas, say beyond 100 miles from the closest Rule airspace, its not a major factor either way because there’s not much traffic by comparison. CTAF or eyes alone works fine when there’s only one other plane in the airport traffic pattern.
For those of us who fly where traffic density is extremely high and where almost everybody is based near a Class B/C airport or veil, even if they’re only nearby that airspace, portable ADS-B IN has completely revolutionized situational awareness in relation to other traffic. Almost everybody is transmitting ADS-B OUT. Obviously that doesn’t prevent a lot of collisions, because there never were a lot of collisions regardless of having two or three planes within a mile when jockeying for position to make your first inbound radio call. However there were a lot of close calls that made flying in those areas unpleasant. They are now easy to avoid and flying a plane to and from e.g. my base is a lot less anxiety provoking for many people.
According to news releases, police helicopter units in several countries including the Norwegian Police Air Support Unit for electronic conspicuity in their drone search, ADAC Luftrettung in Germany for collision avoidance on their air rescue ops have chosen SafeSky to help in MAC avoidance.
With TIS-B the good thing that in some developed countries the national traffic service would pick up all Secondary and Primary targets using normal radars and re-broadcast those using TIS-B. I doubt it will ever happen in the UK though…
arj1 wrote:
With TIS-B the good thing that in some developed countries the national traffic service would pick up all Secondary and Primary targets using normal radars and re-broadcast those using TIS-B. I doubt it will ever happen in the UK though…
I think TISB is only a US thing. In the US, only non ADS-B Out aircraft secondary targets with mode C are broadcast with a TISB (not a re-broadcast) and even then only if the target flies near (+/- 3500 feet and radius 15 NM) a client ADS-B Out aircraft that cares. I say “that cares”, because if the client doesn’t indicate that it has ADS-B In capability, then that client will not cause the ground station to broadcast a TISB target. Most Business Jet and air carriers don’t cause TISB to be broadcast because they don’t care, that is they don’t indicate the aircraft has ADS-B In capability. Primary radar returns and secondary radar returns without mode C don’t end up with a TIS-B being generated. To provide the TISB service, both client and target have to be within ADS-B and radar service volumes, which excludes most airport patterns.
Most of the value is provided by ADS-B Out equipped aircraft, about 80% of the fleet. I very much prefer aircraft equipped with ADS-B In over portable solutions, which I think suffer from a variety of issues such as antenna, and traffic alert algorithms used and often lack of audio.
gallois wrote:
have chosen SafeSky to help in MAC avoidance.
Several people I know use SafeSky. Haven’t really tried it yet.
