What a very sad accident. It seems almost sacrilegious to turn it into an argument about TCAS (etc) vs eyeballs.
Someone asked about the US. I've had TCAD (TCAS without RA) for 15 years (Garmin 330). I feel very uncomfortable flying without it, especially in a heli. The traffic picture is part of my scan, along with the outside. Flying into a busy airport like Palo Alto, it is a huge help. Now I have ADS-B (Garmin 345) which is even better.
A recent example... last weekend I was flying to Auburn, about 120 miles away. For the last 15 minutes there was another aircraft ahead of me on the screen, gradually getting closer, most likely going to the same airport. I kept clear of it using TCAS even though I never saw it until we were both almost in the traffic pattern. Then on the way back out someone got uncomfortably close on the way in, manouvered to be sure to keep clear. I was talking to ATC and so were they, but still very nice to know where they were. Never actually saw them.
And a negative example... descending through 13000 feet in a non-TCAS aircraft (fast) with a VERY experienced ex-mil instructor - saw an A320 pass WAY too close for comfort. Would never have happened with TCAS/ADS-B.
As for weight and cost... the GTX-330 or 345 is like any other transponder, and there is nothing else. You need a display but it couples into a GNS-430 or 530 or similar. My 330 cost about $5K in 2002, the 345 about the same in 2016 - not cheap but relative to the general cost of flying, not ridiculous. And now you can get even cheaper ADS-B In devices that couple to an iPad. Worth every penny, and much more, for the constant knowledge of what's out there.
Last edited by n5296s; 18th Nov 2017 at 17:23.