TCAS safe for ATC?
TCAS is very safe for ATC
There is some excelent reading on the eurocontrol website.
Go to this link http://www.eurocontrol.int/acas/
Select Safety Information and scroll down to ACAS II Bulletins. There are 5 in all and well worth reading. I do not think you will doubt the wisdom of following TCAS once you have read them.
Miles
Go to this link http://www.eurocontrol.int/acas/
Select Safety Information and scroll down to ACAS II Bulletins. There are 5 in all and well worth reading. I do not think you will doubt the wisdom of following TCAS once you have read them.
Miles
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I don't know anything about a 5 degree bank angle limit for avoiding action, but on the 757/767 the TCAS assumes that the bank angle "will be less than 15 degrees for climb performance purposes".
Whilst we are talking about avoiding action (I admit that the following is mainly for the benefit of TMA controllers). When we are slowed to our minimum clean speed (close enough to holding speed as to be no different), a combination of a 30 deg banked turn and g loading and/or turbulence may result in a genuine stick shake warning. With this in mind, when you give an avoiding action turn, the actual turn itself will not be appreciably tighter than those you normally see.
The flap speed schedule only allows for "an inadvertent 15 degree overshoot beyond the normal 25 degree bank angle". We also get a "BANK ANGLE BANK ANGLE" warning when the bank angle exceeds 35 degrees. The up-shot of this is that to keep our heart rates to acceptable levels and to avoid bending the aeroplane we will not be ablt to turn much more quickly than normal in a TMA environment.
I actually had an RA not that long ago, and the concentration required to switch from calculating heights and ranges in order to follow a nice CDA to suddenly fly the aeroplane out of the (growing) red sector was quite stunning. All good fun, but I can categorically state that avoiding action in the horizontal plane is the only useful response from the ATCO and even then, with the flight director showing turn left, the controller saying turn right, the clearance requiring a descent and the TCAS requiring a level off - there was a lot going on!
G W-H
Whilst we are talking about avoiding action (I admit that the following is mainly for the benefit of TMA controllers). When we are slowed to our minimum clean speed (close enough to holding speed as to be no different), a combination of a 30 deg banked turn and g loading and/or turbulence may result in a genuine stick shake warning. With this in mind, when you give an avoiding action turn, the actual turn itself will not be appreciably tighter than those you normally see.
The flap speed schedule only allows for "an inadvertent 15 degree overshoot beyond the normal 25 degree bank angle". We also get a "BANK ANGLE BANK ANGLE" warning when the bank angle exceeds 35 degrees. The up-shot of this is that to keep our heart rates to acceptable levels and to avoid bending the aeroplane we will not be ablt to turn much more quickly than normal in a TMA environment.
I actually had an RA not that long ago, and the concentration required to switch from calculating heights and ranges in order to follow a nice CDA to suddenly fly the aeroplane out of the (growing) red sector was quite stunning. All good fun, but I can categorically state that avoiding action in the horizontal plane is the only useful response from the ATCO and even then, with the flight director showing turn left, the controller saying turn right, the clearance requiring a descent and the TCAS requiring a level off - there was a lot going on!
G W-H
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Giles- as an aside...
How hard was it to follow SOPs? Was the compulsion to follow the human (ATC) instructions strong? Did the controller get notified of what was happening in time to assist/stop assisting, or was he notified after it was all over? I'm just interested as the current system takes the controller out of the loop, without him knowing he is out (perhaps as it should be).
How hard was it to follow SOPs? Was the compulsion to follow the human (ATC) instructions strong? Did the controller get notified of what was happening in time to assist/stop assisting, or was he notified after it was all over? I'm just interested as the current system takes the controller out of the loop, without him knowing he is out (perhaps as it should be).
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Excuse my lateness in posting this but..........
If the TCAS units onboard the A/C "talk" to each other then they mus tx information can this info not be recived and displayed/intigrated with the radar display or is this to far fetched ????
This would enable the controller to be alerted to the TCAS RA and to " keep his mouth Closed??"
Comments its just an IDEA
If the TCAS units onboard the A/C "talk" to each other then they mus tx information can this info not be recived and displayed/intigrated with the radar display or is this to far fetched ????
This would enable the controller to be alerted to the TCAS RA and to " keep his mouth Closed??"
Comments its just an IDEA
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With Mode S TCAS RAs can be downlinked and this is also a recommendation from the Uberlingen accident report.
It's debateable how useful this might be, given the possible timescales of a RA it is quite likely that by the time the downlinked info is on whatever display is put in front of the controller the actual event will be over and done with.
WF.
It's debateable how useful this might be, given the possible timescales of a RA it is quite likely that by the time the downlinked info is on whatever display is put in front of the controller the actual event will be over and done with.
WF.
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From what I understand the information could be recived by an omnidirectional reciver and not subject to the delays of a rotating radar head.
How that info is intergrated is anyones idea it may only be a flahing light on the console!
so in real terms the delay in the controler being alerted in theory should only be 1-2 seconds after the A/c.
If only pigs could fly????
How that info is intergrated is anyones idea it may only be a flahing light on the console!
so in real terms the delay in the controler being alerted in theory should only be 1-2 seconds after the A/c.
If only pigs could fly????
Pegase Driver
45 South :
quote :-----------------------------------------------------------------------
If the TCAS units onboard the A/C "talk" to each other then they mus tx information can this info not be recived and displayed/intigrated with the radar display or is this to far fetched ????
This would enable the controller to be alerted to the TCAS RA and to " keep his mouth Closed??"
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Not that simple. Omni antennas do work, but with a range of 40 Nm max, many RAs are false RAs, and there are a few other problems.
Keeping controllers quiet is also not the miracle solution.
Remember that in Ueberlingen , and in all the other close calls resulting from a contradiction betwen RAs and ATC instructions, the ATC instructions were just BEFORE the RAs or at the same time....
Humans and automation do not mix well. The more I learn and known about TCAS, the more I think the only way out is to link it to the Auto pilot.
Until we come to that ( and we will one day) : Always Follow the RAs like your life depends on it , because it might.
quote :-----------------------------------------------------------------------
If the TCAS units onboard the A/C "talk" to each other then they mus tx information can this info not be recived and displayed/intigrated with the radar display or is this to far fetched ????
This would enable the controller to be alerted to the TCAS RA and to " keep his mouth Closed??"
--------------------------------------------------------------------------------
Not that simple. Omni antennas do work, but with a range of 40 Nm max, many RAs are false RAs, and there are a few other problems.
Keeping controllers quiet is also not the miracle solution.
Remember that in Ueberlingen , and in all the other close calls resulting from a contradiction betwen RAs and ATC instructions, the ATC instructions were just BEFORE the RAs or at the same time....
Humans and automation do not mix well. The more I learn and known about TCAS, the more I think the only way out is to link it to the Auto pilot.
Until we come to that ( and we will one day) : Always Follow the RAs like your life depends on it , because it might.
