There's a lot of mythology touted by the "never in my lifetime" brigade, all of whom have probably never seen TCAS in operation.
Myth: Pilots with TCAS fly with their eyes inside the cockpit all the time and TCAS is therefore a dangerous, counterproductive piece of equipment.
Rubbish! Used properly, as a part of a lookout scan, TCAS makes the pilot keep his eyes looking OUTside. He is made aware of aircraft coming his way WELL before he has any chance of seeing them and can
plan or take early avoiding action if required, to the mutual benefit of both pilots.
I've been lucky enough to have flown aircraft fitted with TCAS (or TAS) for ten years now (and thankfully only a few without). It has proved to me many times, almost on a daily basis, that the human eye is very limited in it's effectiveness at detecting other, possibly conflicting aircraft. (Before the doubters cast aspersions on the limitations on my personal eyesight, it's 6/5 on a class 1 medical).
For example, on Sunday I flew from a landing site "up north" to LHR and back. As it was a fine day (but hazy), there were many aircraft airborne, the length of the country. Heathrow Radar and Northolt Approach stopped giving me individual information on other traffic because there were simply too many to call. I saw most of the ones called by ATC and many others in addition, as well as many others further north. I'm sure I also missed seeing some, we're all human.
At least three aircraft crossed S & L ahead with me firmly on their right side, at the same altitude, passing close ahead without even so much as waggling a wing. Obviously, they should all have given way in that instance but didn't, so I was eventually obliged to avoid them. I presume that these other pilots were aware of the rules of the air and their obligation to give way to an aircraft on the right so I can only conclude that they didn't see me at all, even though I put two pairs of landing lights on to help them!
It's not such a "Big Sky" in Class G airspace these days; it's getting much busier out there, with the performance of aircraft using it increasing, too (the one I currently fly cruises at 155-160 kts).
Another thing to bear in mind is that the ones who are adamant that TCAS and transponders are totally unnecessary are possibly some of those who actually don't see many other aircraft passing by and believe it's less busy than it really is......
