"TCAS RA" Call
This would mean the controller would lose positive identification of which aeroplane is which in the situation at a fairly critical time. Dumb idea.
Of course, if it was a coordinated response, and both transponders went to the same code from within the series, identification would be lost.
Since TCAS units are able to coordinate their responses (you climb;I'll descend) it probably isn't beyond the tech abilities to have the climbing one assign itself, say, 7201, and the descending one 7203 (or whatever.)
Of course, not all ATS systems have the same functionality, so it might be a "dumb idea", but I would have thought, in the wake of Uberlingen, one worth at least investigating.
Yes, it does only take a few seconds to notify a TCAS RA to ATC. Provided the frequency isn't jammed etc.
In our neck of the woods, it states pretty clearly in MATS that control instructions are not to be issued to the aircraft reporting the event or to any other aircraft involved. Which might exclude passing control instructions to a third aircraft, unless it was known for sure not to be involved (yet).
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I reckon if you can't take 1 second to transmit 'TCAS RA' and continue to monitor the PF's flying then you're in the wrong job. Amazingly, depsite many of us not being female, we are able to do more than one thing at a time and looking at the appropriate instruments (with our eyes) and talking to ATC (with our mouths) is really quite easy. There really are far too many precious people around trying to make mountains out of non-existent molehills.
I've had 2 RAs. They were not high workload at all. In both cases the warnings were reacted to smoothly and accurately and the whole thing was a total non-event. By the time the PF had disconnected the autopilot the PNF had made the call. No aircraft doing aerobatics because PNF wasn't monitoring and really quite relaxed.
It is nonsense to suggest the PNF must spend every millisecond monitoring the PF and the usefulness of the call to ATC far outweighs the 1 second during which you might have to use a different part of your brain to carry out a different task.
I've had 2 RAs. They were not high workload at all. In both cases the warnings were reacted to smoothly and accurately and the whole thing was a total non-event. By the time the PF had disconnected the autopilot the PNF had made the call. No aircraft doing aerobatics because PNF wasn't monitoring and really quite relaxed.
It is nonsense to suggest the PNF must spend every millisecond monitoring the PF and the usefulness of the call to ATC far outweighs the 1 second during which you might have to use a different part of your brain to carry out a different task.
I operate a 737 into an airport in southern Europe where we have frequent conflicts with light aircraft, helicopters and military traffic due to the nature of the airspace. Most weeks we get TAs, two or three times a year RAs.
From experience I can say that there is no problem calling the RA.
The last RA was with a Tornado five hundred feet below passed a couple of miles ahead from left to right whilst I was in level flight on autopilot. In that case the effective risk of collision (with two military aviators looking out I hope) was virtually nil. I strongly believe that when you get used to this happening all the time you react more calmly and there is often no major flight control input required.
The EASA safety bulletin a couple of weeks ago about RAs also suggested that people were deviating excessively in response to RAs. Having said that I do wonder if I am becoming too blase about the whole business. I would certainly be happy if this bit of airspace could be made safer.
From experience I can say that there is no problem calling the RA.
The last RA was with a Tornado five hundred feet below passed a couple of miles ahead from left to right whilst I was in level flight on autopilot. In that case the effective risk of collision (with two military aviators looking out I hope) was virtually nil. I strongly believe that when you get used to this happening all the time you react more calmly and there is often no major flight control input required.
The EASA safety bulletin a couple of weeks ago about RAs also suggested that people were deviating excessively in response to RAs. Having said that I do wonder if I am becoming too blase about the whole business. I would certainly be happy if this bit of airspace could be made safer.
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Whoooahh!
Aviate - Navigate - Communicate still applies!
Nothing has really changed, only the words. However, it is reasonable to expect one person of a multi-crew cockpit to have the spare capacity to make a five second transmission in a timely fashion. But should the workload, due to other factors be so great, the rule above applies.
PM
Aviate - Navigate - Communicate still applies!
Nothing has really changed, only the words. However, it is reasonable to expect one person of a multi-crew cockpit to have the spare capacity to make a five second transmission in a timely fashion. But should the workload, due to other factors be so great, the rule above applies.
PM
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On dear :(
This thread demonstrates the biggest problem that we have with TCAS at the moment.
Pilots and Controllers are not receiving adequate training!
We have examples of:
- Not understanding how TCAS works in reqards to the transponder fit in the intruder.
- Not understanding the rationale behind established SOPs.
- Incorrect TCAS R/T phraseology.
Plus a healthy dose of 'one size fits all'. Yes, many a TCAS RA will be relatively low workload for the non handling pilot; but in some types, in some situations, the workload may be very high.
Folks:
- it is important that the TCAS RA call is made, and that it's made ASAP that the RA is generated.
-It is far more important than routine communication because it potentially influences the flight path of the the other aircraft and therefore must be high on your priority list.
- This is especially true if the other aircraft is non TCAS, (or its inhibited for some reason).
When avoiding action is given by ATC around the same time that an initial RA is generated there is a substantial risk that one aircraft will already be manouevering in the opposite sense to the RA that is generated. No Problem: RA reversal logic kicks in, situation should be safe again.
But if ATC don't get a TCAS RA call, they have to assume they are still responsible for seperation. All it takes now is one more pitch change in the wrong sense and it's game over because TCAS can only reverse once per encounter, and that already happened right at the start.
Essentially, the effect of YOU calling "TCAS RA" should be to make the OTHER aircraft maintain its flight path rather than potentially manoeuvering back towards you.
Hence:
Specified R/T procedure = A good thing.
Maintaining Radio Silence = A bad thing.
pb
Pilots and Controllers are not receiving adequate training!
We have examples of:
- Not understanding how TCAS works in reqards to the transponder fit in the intruder.
- Not understanding the rationale behind established SOPs.
- Incorrect TCAS R/T phraseology.
Plus a healthy dose of 'one size fits all'. Yes, many a TCAS RA will be relatively low workload for the non handling pilot; but in some types, in some situations, the workload may be very high.
Folks:
- it is important that the TCAS RA call is made, and that it's made ASAP that the RA is generated.
-It is far more important than routine communication because it potentially influences the flight path of the the other aircraft and therefore must be high on your priority list.
- This is especially true if the other aircraft is non TCAS, (or its inhibited for some reason).
When avoiding action is given by ATC around the same time that an initial RA is generated there is a substantial risk that one aircraft will already be manouevering in the opposite sense to the RA that is generated. No Problem: RA reversal logic kicks in, situation should be safe again.
But if ATC don't get a TCAS RA call, they have to assume they are still responsible for seperation. All it takes now is one more pitch change in the wrong sense and it's game over because TCAS can only reverse once per encounter, and that already happened right at the start.
Essentially, the effect of YOU calling "TCAS RA" should be to make the OTHER aircraft maintain its flight path rather than potentially manoeuvering back towards you.
Hence:
Specified R/T procedure = A good thing.
Maintaining Radio Silence = A bad thing.
pb
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TCAS can only reverse once per encounter
make a five second transmission
Back when TCAS was developed, pilots were insistent that the TCAS not be a command, but an advisory, hence, Resolution Advisories and not Resolution Commands. Now you say it's going to be automatic. Uh, oh; Big Brother is taking over.
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Fratemate,
Yes this is correct. Although now that I read what I wrote, it is a little innacurate because I said:
This is perhaps a little misleading because you aren't like to get a reversal at the very beginning of an RA, TCAS needs several seconds to assess the danger (I forget how many exactly, I no longer have a primary role as a TCAS insructor and I fly a desk these days). Then you need to fly the reversal. So we're are probably at least 15 seconds into the encounter. So at low altitudes there probably wouldn't time for a second reversal anyway.
Of course this doesnt change the basic thrust of the arguement - we want the intruder to stop manouevering asap, and the best way to do that is to get ATC to stop controlling it with the call.
pb
Yes this is correct. Although now that I read what I wrote, it is a little innacurate because I said:
TCAS can only reverse once per encounter, and that already happened right at the start.
Of course this doesnt change the basic thrust of the arguement - we want the intruder to stop manouevering asap, and the best way to do that is to get ATC to stop controlling it with the call.
pb
Warning Toxic!
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Look, it's quite simple. Obey the RA, don't overdo it, don't underdo it. It tells you exactly what to do. PF does not prevaricate. PNF observes outside, monitors correct response and makes an urgent 'TCAS RA' call when he can! What is the problem? We all know frequencies can get busy. You work with the tools you have, not the tools you would like to have. A congested frequency can still be handled. The most important thing is Aviate. Correct response is all important. The Communication is not so vital. Let's not make problems where none necessarily exist!
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Correct ATC call
Reading this thread I keep seeing people saying "TCAS RA" call. Is this the correct phraseology? I learned the call as "#callsign# TCAS Climb/Descent"...
danishdynamite, it's a Dash 8, you're right, RAs shouldn't be given below 900 which is why I ignored the RA (that, and that it was telling me to dive into the ground.) It had a faulty radio altimeter feed to the TCAS so the TCAS wasn't being inhibited at the appropriate times. The traffic was an aircraft on the ground that had recently vacated the runway.
