ICAO needs to ensure that all pilots know to follow TCAS when its instructions are contradicted by ATC, and all ATCOs need to provide turns rather than climb/descent for avoiding action.
In an ideal world this would be how things are done, as I alluded to in my previous post. But there are two problems before we achieve this utopia:
1) With some pilots there will always be a shred of doubt when ATC instructions contradict TCAS. And more importantly:
2) There is NOTHING (yet) set down in ATC training to suggest that avoiding action TURNS are best practice when an Airprox is occurring, and pilots are probably reacting to RAs.
In fact, at Swanwick, there must be any number of instructors, even local competency examiners, who suggest that vertical avoiding action is the best way to go. Purely on the basis that 1000ft is easier to achieve than 5 miles, and the good book says that in a loss of separation situation we must "use every means at [our] disposal to obtain the required minimum with the least possible delay". Sounds good, but it's hardly helpful when half the instructors AND the air traffic manual are working AGAINST what is clearly common sense.
TCAS is a
brilliant piece of kit. I have seen radar replays of an incident where it managed to keep FOUR aircraft apart, when a Gatwick outbound off 26L was cleared to climb to FL130 towards DET when there were two in the hold at BIG and another coming in from the south to hold at FL110. Left to its own devices, TCAS will keep things apart.
Unfortunately the pace of change in the ATC procedures world is slow, and the pace of common sense is often slower....
LTP