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The "Mk 1 Eyeball" / lookout / see and avoid are almost totally useless

Thread drift back to original pdf. There didn’t appear to be any mention of familiarity with what your looking for. In 1964 at Thruxton I saw aircraft frequently. Regaining my PPL in 1987 at Inverness, I never saw an aircraft off circuit, and today I don’t see many.
Is “Gestalt” psychology now completed debunked?

Maoraigh
EGPE, United Kingdom

Silvaire wrote:

with traffic density many times beyond anything I’ve seen in Europe

I totally endorse that and I think that the often repeated mantra that UK airspace is “busy”, or even “busiest in world”, etc. is simply a reflection of the lack of actual experience of serious VFR flying in the US amongst the ‘sky god’ community here. What is true is the UK has some of the worst designed airspace in the world and in the absence of flight following only chaotic and capricious radar services for VFR traffic.

LeSving wrote:

The traffic flow near an airport is fairly structured and a few words convey a lot of meaning – particularly in regard to what the plane will do next, which no electronic system is good at.

If only that were true in UK. In reality, aerodrome (we are not allowed to say ‘airport’) traffic is just as chaotic as the airspace around them because patterns (‘circuits’) are hugely extended and mis-shapen due to the prevalence of complainers, who can make lots of money out of house prices if they can throttle aerodrome traffic. The net result is that circuit traffic is often not where it says it is and so EC is probably at it’s most valuable close in! (A traffic saying it is ‘downwind’ can be two miles from the runway, stretching the ability of Mk1 eyeball. That’s why we have the ‘overhead join’, adding more chaos in an attempt to pick up these unpredictably placed traffics.IMHO.)

Since it’s an inescapable fact that we will never get flight following (because of the numerous little ATC empires jockeying for position) or regularised patterns (because of house price complainers) that we have to accept chaos for ever, with EC being the one way out. Especially if we can reach a stage when pervasiveness of the equipment means looking out of the window is for sightseeing, with actual traffic management being an EC function.

EGBW / KPRC, United Kingdom

Silvaire wrote:

The traffic flow near an airport is fairly structured and a few words convey a lot of meaning – particularly in regard to what the plane will do next, which no electronic system is good at.

A excellent point. Things are being mixed here. The purpose of the FLARM is to augment SA when flying in close proximity to other aircraft, and to warn when you are too close. The purpose is not to avoid traffic, it is to make it safer to fly very close in extremely dense traffic. Does it succeed in doing that? I don’t know, I have heard both from glider pilots. It has no use whatsoever if the standard rules of flying that close are not obeyed, because it does not show any information of what the other pilots will do next. Flying in a predictable manner is the essential tool to avoid collisions, FLARM or no FLARM.

It is exactly the same near airports. Predictability is the major tool. In a controlled airport predictability is implicit in clearances. At non controlled fields, predictability must be obtained through radio and the structure of flying in the pattern. This principle can be extended to all airspaces, but at some point the aircraft density becomes so small that it becomes irrelevant.

What I read in this thread is people using devices to avoid airspaces. If this is the case, then these devices have failed altogether, because you can avoid those airspaces just fine without those devices. It’s not exactly rocket science to figure out where airspaces with dense traffic exists. At best, those devices will prove that your predictions were right. If those devices don’t increase your ability to fly in a dense airspace, or increase your safety when flying in a dense airspace, then why use them?

The elephant is the circulation
ENVA ENOP ENMO, Norway

If the aircraft is ADS-B Out only and relies on portable receivers, the settings should match the receiver. If it is a rental aircraft, I would recommend just set UAT.

I am not a believer in portable traffic receivers, there are too many issues, particularly in a metal aircraft without using an external bottom mounted antenna as the airframe can block reception of the relevant ground station. Unlike weather, for which there is generous overlap of weather products and often multiple ground stations have overlapping coverage, the TISB/ADSR products, for a given client, are only broadcast on a single ground station. The ground station chosen is the one with the best signal from the client ADS-B Out and assumes the receiver has a bottom mounted antenna. So there is a greater chance that the airframe will block reception of the TISB/ADSR. It does not matter if you are simultaneously receiving from 7 towers if the one you need to receive from is blocked. Also, there isn’t an indication that the TISB/ADSR service is being provided, so if you don’t see traffic, is it because there is non or you just happen to be blocking the ground station or have flown out of the service volume. These indications are provided with panel mount systems and the panel mount system uses a bottom mounted antenna. Panel mount solutions also use different methods of generating traffic alerts and frequently tie into the audio system, example an audio alert on my system gets my attention “Traffic 12 Oclock, same altitude, less than a mile”. Finally, with a built in system, own ship location and pressure altitude is known, so relative altitude with respect to targets is based on an apples to apples comparison. With a portable solution, an algorithm has to be used to determine own ship as all ADS-B Out broadcasts look the same, even the one a few meters away on the belly.

KUZA, United States

NCYankee wrote:

The reason that your GTX 335 has to specify the ADS-B In capabilities you have on board is to let the ground station know what services you are to receive and on what frequency

Everybody I’ve spoken to turns both IN bands on to cover any portable equipment that may be in the plane at any time in the future. Since most portable receivers are UAT minimum, 1090ES maybe, it sounds like setting ‘yes’ for UAT IN and not 1090ES would be a better default setting ensure getting ADSR. In my case, with a dual band receiver, both are turned on.

Thanks for the explanation – it’s useful to understand the details but I doubt many GTX 335s will be pilot configured to account for the portable IN situation on any particular day, regardless of consequence. This stuff is ridiculously complex, and basically unattractive.

Last Edited by Silvaire at 08 Aug 13:57

Graham wrote:

I didn’t get into a vintage aeroplane to play with electronic devices. This goes as far as not mounting a tablet or phone – if I want to use SkyDemon in the Vagabond it’s on my phone and in my hand/lap.

I surely understand that. When I had my non-electrical Luscombe, I approached this problem by mounting my phone nicely in view with a suction cup mount. It worked very well and was removed after every flight in about a second.

Silvaire wrote:

The plane was until recently ADS-B portable IN only, but now has newly installed GTX 335 1090ES ADS-B OUT. In my area this change generally has no effect on IN as there is always another aircraft close by that is requesting the data.

That is not easy to determine, even in a high density traffic area because you will see tons of traffic either way. Having ADS-B Out and as you noted setup to report to the ground station what frequencies you are capable of receiving ADS-B In will make a significant difference, but only to spotting close in traffic.. So if you go from 120 targets to 121 and the extra 1 is close to you and represents a collision risk, the extra 1 is the only target of interest. Ground stations only generate traffic on behalf of valid clients, but because they are broadcast and contain their location in the data, any receiver can display the traffic, even if it is not on their behalf. This gives one the mistaken impression that someone else’s traffic covers them. It may or may not. For aircraft just using a receiver, what they miss without also having a properly configured ADS-B Out is their own close in traffic. If the receiver only aircraft is within the hockey puck of an equipped aircraft, the ground station will generate a TISB for the unequipped aircraft location and it will appear as a ghost to the unequipped aircraft. Some systems will filter the ghost out, but as you enter the puck of the equipped aircraft, you are at its edge in terms of distance and altitude, so you can have traffic in your immediate vicinity that is not in the puck of the equipped aircraft, because it is his traffic, not yours. Adding the ADS-B Out makes you a client and the ground station generates TISB for traffic centric on your altitude and position.

The reason that your GTX 335 has to specify the ADS-B In capabilities you have on board is to let the ground station know what services you are to receive and on what frequency. This information is broadcast by your GTX 335 to the ground station and it uses the information according to the following truth table:

No ADS-B In – ground station does not generate any TISB or ADSR on your behalf
UAT ADS-B In – ground station generates TISB and 1090ES ADSR on UAT frequency
1090 ADS-B In- ground station generates TISB and UAT ADSR on 1090ES frequency
Both UAT and 1090ES ADS-B In – ground station generates TISB on UAT frequency but does not generate any ADSR

TISB is a mode C only target, ADSR is a rebroadcast of ADS-B from one frequency to the other frequency to cover single frequency ADS-B In capability

KUZA, United States

I spent $5K getting my $35K plane set up with certified 1090ES ADS-B OUT (Garmin GTX 335) and uncertified dual band IN (Stratus & Foreflight), doing much of the work myself and relying on (very low paid) friends for the rest. It has been the most frustratingly bureaucratic and time consuming thing I’ve done to my planes so far. I could have done it for about $4K (or perhaps a little less) using less expensive hardware (no transponder replacement) and the approval process would have less onerous. Still a big deal, and if I have to do anything like it ever again the plane will be sold and I’ll find other ways to amuse myself. I don’t like dealing with Garmin, the extra electronics crap in the plane, the wart like GPS antenna etc, but it seemed like the best way to do the job with hardware that would last a long time.

Mid-airs are not a major risk here, but certainly one that gets your attention. We have a mid-air about once every couple of years in my local area, with traffic density many times beyond anything I’ve seen in Europe – where the skies are mostly empty. My reason for getting ADS-B IN was mainly curiosity. It’s interesting, but I’m finding it not as useful as I’d hoped, and it’s one more thing to maintain. I’ll continue to use it but don’t see it as a major life saver. If and when my Stratus system is obsolete, it probably won’t be replaced but we’ll see, tools improve over time.

Everybody (and many environments) are different but dealing with this stuff is not flying to me, it’s a substantial, costly distraction that addresses a modest risk while also in my case allowing every flight I make to be tracked.

Last Edited by Silvaire at 08 Aug 12:26

Timothy wrote:

Let’s hope that’s not your last word on the subject

Indeed, let us hope not.

I call it the Schumacher effect.

This thing that was not really a problem before is now suddenly a massive problem that needs a solution. I have not been skiing for some years (pre-Schumacher) and when I last went almost nobody wore helmets. I will go this winter coming, and I am not sure whether I’ll wear a helmet or not but I understand that now nearly everybody does.

Yet nothing has really changed risk-wise. People have just become very aware of a particular risk (regardless of the level of that risk) and decided that it must be mitigated against.

The mid-air / EC thing is the same.

EGLM & EGTN

Mooney_Driver wrote:

Not really. You can get portable devices which do everything (ADS-B, Flarm, Mode C) which are totally independent with rechargable batteries. A device like this will also radiate your position at least for other Flarm users.

I’m aware of this of course, but my flying in the Vagabond is of a very raw, basic kind and that’s how I like it. Carry boxes and wires with me to the aircraft, making sure things are charged, filling the cockpit with gadgets and setting them all up before going for a quick jaunt…… it’s not really part of my philosophy in that aeroplane.

Call me a weirdo, but it’s just how I like it. I didn’t get into a vintage aeroplane to play with electronic devices. This goes as far as not mounting a tablet or phone – if I want to use SkyDemon in the Vagabond it’s on my phone and in my hand/lap.

EGLM & EGTN
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