Synthetic VOR/DME

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Originally Posted by ShyTorque

Knowing where you are in relation to a VOR should come from the mental picture formed during thorough pre-flight planning and map study.

I don't necessarily agree with this statement. Yes, I know where I am in relation to a particular VOR, if I'm using that VOR myself for navigation. But if, during my pre-flight planning, I chose to navigate using landscape features (roads, railways, rivers) or maybe the magenta line on the GPS, and then I get a position report with reference to something else (a VOR, or maybe an obscure town), then I'm going to have a hard time figuring out whether something is a threat or not. And this is of course made worse if you're flying in unfamiliar airspace, or even in a foreign country, and the local pilot pronounces the local town name with a local accent. A lot of languages are far from phonetic.

So if I'm flying in class G and I hear a position report from another pilot and I can place it immediately, I might register it and do something with that information. But if I can't place that report immediately, I'm just going to disregard it. Like I said before, it takes me too much time, and too much heads-down time, to figure out what that report means in the first place and whether he constitutes a threat to me. And by the time I have figured it out, he has moved on anyway. Looking outside and assuming everybody flies around without making position reports is a far better strategy IMHO.

Edited to add - I'm only doing position reports in class G when I'm staying in a particular area for a longer time, and especially if I know my lookout is going to be less than optimal. For instance when doing a photoshoot, or when flying aerobatics. And even though this is class G and there are no guarantees, I'm always hoping that the FIS will inform other aircraft of my intentions if they happen to come near my location.

[bingofuel]

I am curious how you deal with the threat of aircraft who do not ‘announce their position’ ? There are many aircraft out there, some do not even have a radio ( shock , horror!) and the only realistic way to avoid getting close to them is to maintain a very good lookout utilising the mark 1 eyeball!

[Maoraigh1]

Agree with look out. To locate a position given relative to VOR will often take time looking at a map, paper or electronic.
Disagree with knowing every possible reporting point in preplanning for a long VFR flight into a densely inhabited area, especially with changing plan to avoid weather.
Pessimistic on lookout though. I was given an aircraft 3 miles and 500' distant by radar, and altered my course and height, saying what I was doing. We were both on radio, same frequency. But with low sun and haze visibility into the sun was poor, though good in every other direction. I never saw it.
I was lucky to get a warning from ATC in the US as I descended a C172 in ignorant formation below a Pa28, excellent visibility, and no other traffic near.

[double_barrel]

Originally Posted by bingofuel

I am curious how you deal with the threat of aircraft who do not ‘announce their position’ ? There are many aircraft out there, some do not even have a radio ( shock , horror!) and the only realistic way to avoid getting close to them is to maintain a very good lookout utilising the mark 1 eyeball!

Originally Posted by Maoraigh1

Agree with look out. To locate a position given relative to VOR will often take time looking at a map, paper or electronic..

So I should ignore the information I get from those who do announce their position?

I must say I find this conversation a bit strange. I hear that it's important that I have my 'eyes out', but that is the whole point of my suggestion. I want a super simple way of judging where I am relative to aircraft I hear on the radio, without fiddling around with charts or ipads. Glancing at 2 numbers every few minutes does not seem too demanding, should I also not occasionally glance at the T's and P's for fear of hitting something?

As I have said, I am sure that I am by far the least experienced, and I am here to learn, but I wonder if I am hearing a bit of puritanism from those who don't like it to be too easy? In my other activities, there used to be similar discussions, eg insistence that AIS or VHF is dangerous for collision avoidance, or shock horror at navigating by GPS. All these concerns are real, and misuse or blind over-reliance can be dangerous, but that does not mean you should not make appropriate use of all the tools at your disposal.

It may also be worth adding that I think the environment I fly in may be a little unusual. When I am flying cross-country at 9,500', those around me are mostly professional pilots who are IFR capable, but who choose to fly VFR 90% of the time. They are typically also flying unpressurised and slowish a/c such as Caravans (because they are mostly delivering tourists to small airstrips) and we are all looking for the best groundspeed, VMC, O2 and healthy terrain clearance, so we all end-up between 9,500 and 11,500. They have shiny G1000 cockpits and rarely bother with local reference points, and when they do it's often not a name that means anything to me. So when they finish-up with 'and showing 130 degrees and 55 miles from the NAVEX', that's a super useful piece of data for me that I would like to use appropriately.

[Jan Olieslagers]

So I should ignore the information I get from those who do announce their position?

Do not think "black vs. white", please. ALL information you get - not only when piloting - is to be taken for what it is worth. For what YOU judge it worth, that is.

[Maoraigh1]

I treat position information on radio seriously, but keep my eyes out, relying on a rough idea of where they are. Will often respond stating my position, if we're not both getting radar info.
Safetycom is now much used where I fly, but I don't go head-in to plot positions on a map.
Height and intention are often more useful. I just hope the guy on a conflicting track 2000' above me doesn't have an engine failure and radio failure.

[BackPacker]

Originally Posted by double_barrel

So I should ignore the information I get from those who do announce their position? [...]

Let me turn the argument the other way around. Suppose, for a minute, that all VFR aircraft do position reports, that all these reports are dead accurate, that there is a common set of reference points (VORs, for arguments sake) that everybody knows and uses, and that they do this position reporting often enough so that the information stays relevant and accurate until they do the next position report.

You mention that you fly in the neighbourhood of 10.000 feet. At that altitude, the horizon is a little over 100 miles away, and you can hear transmissions of aircraft at 10.000 feet at double that distance - almost 250 miles away. In other words, you are going to hear all the position reports of all aircraft in an area that's about 200.000 nautical miles squared or well over 600.000 km^2 - approximately an area equal to the whole of France. Any idea how many VFR aircraft are out and about in France on a good day?

(For fairness sake, I'm assuming that this area is served by a single FIS/Unicom/whatever frequency, which is probably not the case. But that's hardly relevant. I'm just trying to get the point across that there's a vast area within line of sight, and thus within VHF range, at 10.000 feet.)

How many aircraft would be flying around such an area? Your post suggests that there's a fair bit of traffic about, and in that statement I'm assuming you're talking about the relatively close area. For arguments sake, let's be pessimistic and assume that there's 100 aircraft operating inside this 600.000 km^2 area. For position reports to be useful for other traffic, my gut feeling is that they should not be more than 5 minutes apart - your average GA spamcan covers at least 10 NM in that timeframe. So you now have to process 100 position reports every 5 minutes, or one every THREE seconds.

Can you do a position report yourself in less than three seconds? Is the frequency you're operating on really this busy with position reports? Can you interpret a position report within three seconds?

Heck, even if there's only ten aircraft on your particular frequency, then that still means a position report every 30 seconds. And each and every one of those needs to be interpreted, in addition to all the other mental tasks that you've got to perform as a pilot.

So for all practical purposes, position reports simply don't work, especially not for aircraft going from A to B at 100+ knots. So the vast majority of pilots don't make them in the first place, or at least not often enough to be practically useful. So you've got to assume that 99% of the traffic that you might encounter, has not made a position report at all. For the other 1%, is it worth spending an immense amount of mental energy interpreting their position reports? Or should your time be spent doing other things, like looking outside?

Position reports don't keep you safe. What keeps you safe is looking outside, TCAS/PCAS/Flarm or something similar, some form of radar/traffic information service, and the fact that the sky is really, really big and aircraft are comparatively very, very small.