The TCAS won't descend you into a mountain, EGPWS has priority. Yes, Pitbull, if you don't follow the RA, the coordinating aircraft will have a RA of greater magnitude, but following it is the correct response. The San Diego B727/C172 crash occurred when the pilot's thought they had there traffic "in sight" when the real conflict was not in their sight. If they had a TCAS II RA, decided the plane they had in sight was not really a conflict, they would have had the mid-air. Follow the RA.
I'll tell you what Galaxy. Why don't you stop putting 'head banging into wall' symbols and start actually reading posts.
The TCAS won't descend you into a mountain, EGPWS has priority.
Agreed. You should be safe against ground contact. With a caveat: Check your MEL. Can you dispatch with the E part of EGPWS inop?
Yes, Pitbull, if you don't follow the RA, the coordinating aircraft will have a RA of greater magnitude, but following it is the correct response.
Wrong.
Both aircraft will get their initial RA's. The only way aircraft B will get a strengthened RA is if aircraft A manoeuvres in the opposite sense. If aircraft A does not follow, or is slow to follow, or can not fully comply (e.g. makes +500 instead of +1750), then this will have no effect on the type of RA received by aircraft B.
The San Diego B727/C172 crash occurred when the pilot's thought they had there traffic "in sight" when the real conflict was not in their sight. If they had a TCAS II RA, decided the plane they had in sight was not really a conflict, they would have had the mid-air. Follow the RA.
I'm not sure if this is directed at my post, but it's in a continuous paragraph from where you refer to me by handle, so I presume it is.
Nowhere have I suggested that RA's should be ignored if they are considered to be unnecessary. On the contrary, I've been singing the "Think its not needed? So what, follow it anyway" tune ever since TCAS was mandated, even though the 'official' guidance didn't change to that until several years later.
The pilot has the ability to be aware of multiple hazards that TCAS simply can not analyse. i.e. anything that doesn't have an altitude encoding transponder. As such, it is possible that the act of following an RA may, in itself, be immediately hazardous. Do you dispute this? I know its a bit unpopular, but I believe that a crew might be required, from time to time, to excercise some judgement. But you know what? We could argue the toss on that one all day. The reality is that the perception of non TCAS risks depends on the type of operation. An air transport / IFR / controlled airspace / major airport pilot will have much less concern than someone who operates into places buzzing with non transponding traffic. So I suggest we just put that aside and just concentrate on the original posters issue; i.e. Performance.
The point I'm making is very simple, so I'll spell it out:
An RA may not be achievable.
Yes, TCAS has performance inhibitions. But you really need to appreciate that these are NOT comprehensive. I'd classify them as 'inhibiting the totally impossible' rather than 'guarunteeing the possible'. In addition to that, TCAS (probably: type dependant) doesn't know about engine failures / flight control malfunction. It doesn't know if you're covered in Ice.
Dispute it all you like, bottom line is that the pilots job has to be to protect the flight envelope, including if necessary not fully complying with an RA.
Don't want to take my word for it? Why not take a TCAS manufacturer's:
"The pilot
must not exceed stick shaker or other stall warnings or protections when following an RA"
That's from a manufacturers manual, not just whatever sections your management pilot saw fit to put in your ops manual.
You may NOT be able to follow an RA. You MUST KNOW what to do if you can't.
pb