Hmm cant imagine that much traffic around in a combat zone, I guess you lot arent doing your job very well if you havent managed to supress most of it.
Air superiority isn't an issue with respect to suppressing traditional threats. The real threat are unmanned aerial vehicles, and thus far every incident I've had has been a UAV. The air is thick with them. It's worse in other locations. Unfortunately, radar is sporadic, as is traffic that reports or talks. The way airspace is assigned is very different, too.
In the case of PCAS, it won't detect another transponder unless it's being actively interrogated by either a TCAS unit, or radar. This means that targets can suddenly pop up inside the range settings of the PCAS unit without warning, and disappear, quickly as well. The update rate on them isn't good, which probably isn't a problem if one isn't doing much maneuvering or turning. The unit also delivers only very rough approimation as to azimuth or bearing from the user, and even with the screen displaying a dot for the position of the intruder...the refresh rate is slow enough that traffic is often not where the unit says it is because the angular difference has changed in a turn.
A frequent error I see is traffic appearing to change altitudes. Sometimes it's obvous and rapid, but sometimes not. A change of five hundred feet or so instantaneously can be identified as an instrumentation error, but when watching the traffic being monitored descending a few hundred feet and going back up again...one can't really be sure. In some cases I wasn't sure if the warnings I received were real or not..but a few times now I've verified it visually...in the dark.
Point being...these devices are probably better than nothing, but in my opinion, not much more so. Certainly installing TCAS is prohibitive in most cases, but I think knowing the limitations of the equipment is every bit as important as knowing what it *may* be able to dofor you.