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

Ok, so many people with TCAS don't see most of the traffic that shows up on the TCAS unit. Is there any way of verifying that the TCAS unit is displaying traffic accurately? Could some of the traffic be "phantom" traffic? Just wondering.

I don't think it's surprising though that we can't spot most traffic. Consider trying to spot a particular car that's two miles away while you're driving on the motorway. Now consider that that same car could be above or below you by 1000ft. And it could be traveling in any direction, not just toward you or away from you. And your mind is occupied with controlling the vehicle, navigating and listening to the radio. Many GA aircraft aren't that much bigger than a car.

I think the only way to solve mid-airs would be mandatory transponders and mandatory TCAS in all flying machines. But that's not going to happen for many reasons.

Fairoaks, United Kingdom

KWLF stated:

I'd be willing to bet that within the next decade drones will use cameras to see-and-avoid better than we can. Perhaps we'll get to use whatever they end up using - the advantage being that you don't have to get everybody to agree on a common protocol for a collision avoidance system, which technically would otherwise be a relatively trivial exercise.

I like this thinking...Bionic see-and-avoid!....totally passive system...presumably only good in VMC but then again most likely it is VFR traffic that is going to get you...

YPJT, United Arab Emirates

We turn to the right because ships turn to the right. I suspect that ships turn to the right because on waterways, they also have to keep to the right. I suspect that they have to keep to the right on waterways because Napoleon was left handed.

Yes, but Europeans and Americans drive on the right, sail on the right and fly on the right.....here in the UK we drive on the left...and since most of us drive every day the instinct to pull left when faced with oncoming traffic may well translate into the same response in the air when faced with a split second choice...when the correct response would normally be to turn to the right

On a purely unscientific basis, I notice that in the US and Europe, in general there is less pedestrian conflict ie people all seem to walk on the right whereas in the UK and Australia there is often more indecision about which way to turn when faced with oncoming people...it leads me to think that it is more natural to turn to the right (possibly related to whether you are left or right handed) and in the UK this natural tendency is over-ruled by the rules of the road....

YPJT, United Arab Emirates

There are a vast number of studies on this and there is no known "natural" direction. It is entirely cultural.

EGTK Oxford

Fair enough...I will accept there may be no natural preference...it was my unscientific observation....but what do you think about the conditioning theory of driving vs flying responses?

YPJT, United Arab Emirates

Handedness is a pretty fundamental property though, so frankly I would be surprised if there truly is no natural inclination to turn to one side or another. A while back I had a plague of flies that kept buzzing round the lamp on my bedroom ceiling, so I hung some fly paper from one side of them. One side of the fly paper caught dozens of flies. The other side only caught one... So I watched them for a little and found that they were all flying round the lamp in the same direction (counterclockwise, IIRC).

On the other hand, from an evolutionary perspective, you could argue that if a predator is attacking you, the optimal strategy is to break in a random direction. Locusts break in a random direction if attacked.

I thought the reason for turning right in a head-on situation is because it keeps the conflicting traffic to your left, where you can keep an eye on it because you sit on the left (in a fixed wing plane).

If you turned left then as soon as you start turning you might lose visual contact with it, which is a very bad idea.

Is there any way of verifying that the TCAS unit is displaying traffic accurately? Could some of the traffic be "phantom" traffic? Just wondering.

A single return, which just briefly pops up, certainly could be.

But you can't get a phantom return which is moving in an obviously "intelligent" manner, on a reasonable trajectory.

Especially if it is Mode C and thus showing a relative altitude.

The portable products (ZAON I believe is the only one currently which does azimuth) suffer from phantom returns a lot, partly because they have no barometric altitude of their own, so they receive your own transponder's emissions to get your pressure altitude. They also occassionally receive your own transponder's emissions and think it is another plane very close... Some people find them quite good while others find them variously useless.

The fixed systems connect into your transponder RF output cable, and into your DME, so it can properly disregard these emissions, and it gets the pressure altitude via a wired connection to your encoding altimeter (usually this is taken from the back of the transponder, which also has this input).

Administrator
Shoreham EGKA, United Kingdom

I thought the reason for turning right in a head-on situation is because it keeps the conflicting traffic to your left, where you can keep an eye on it because you sit on the left (in a fixed wing plane).

Apart from being the rules of the air as well...

YPJT, United Arab Emirates

Yes; what I was thinking was perhaps that it was done that way for a good reason

That said, the last time I had a head-on (near the Isle of Wight) I turned right and the other pilot turned left, so I had to make the turn pretty sharp...

Administrator
Shoreham EGKA, United Kingdom
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