what would you do?

[purple haze]

i was watching a prog. on discovery a couple of days ago.

an ATC was being interviwed, and she said her scarest moment was when she allowed to a/c to fly close together.

and she literally closed her eyes and waited to see if the two a/c was cross each other without crashing.

now the problem pilots were having was their TCAS was giving the opposite advice to the ATC.

my q. is simply what would you do and how could this situation arise.

the ATC was at dallas. and the atc was so shook up she took a yr off.

[Bluejet]

Hm, a question asked fairly deserves a fair response, regardless of spelling etc.

Mistakes happen. So it is not impossible that an error made by an individual could result in aircraft becoming overly close. Instances such as these are not solely the domain of ATC. Pilots hear the wrong clearance, or react to avoid weather without telling ATC etc etc all can combine to cause the situation you mention.

The primary task of all flight deck is to safely aviate the aircraft. We have a nuber of tools at our disposal to do this. A particualry useful tool is, as you mentioned, TCAS. it gives lots of information, in lots of modes In the event of aircraft getting too cose it gives a Traffic Advisory (TA), and displays the offending aircraft as a solid shape on your screen. it also says 'TRAFFIC TRAFFIC' to get your attention. These are warnings for you to get the old mark one eyeball on the move to identify the threat. If the threat gets very close (within 15 seconds) it gives you a Resolution Advisory (RA). This is an instruction to climb, or descend to escape the traffic. Very modern TCAS liase with the other aircraft, and give all sorts of escape information.

To answer your question, in our company, a TCAS RA is a mandatory instruction, and we go with that. There is not really the time to talk to ATC etc and get vectors, jets close too quickly for that. So if ATC was telling us to do something and we got a TCAS RA, we'd go with the RA. However the Non Flying Pilot would tell ATC what we were doing as we did it i.e. "Radar, CALLSIGN TCAS RA climbing"

Hope the above helps.

[OnTheStep]

if a resolution comes up- resolve!

work the rest out later :)

[englishal]

Actually in this case it was the TCAS which caused the conflict. The controller told one plane to climb, the other to decend to maintain seperation. Both TCAS's then issued traffic alerts and subsequent RA, the RA in the climbing aircraft instructed the pilot to decend, and the RA in the decending aircraft instructed the pilot to climb, totally contradicting what the controller had just instructed and resulting in a very near miss (or near hit??).

[Sagey]

First post is factually incorrect as pointed out previously.

She didn't take a year off, she stated that she was more cautious at work due to the incident and it took her a year to put it out of the back of her mind. She took two weeks (or was it a week?) off after the incident.



Sagey

[phd]

Purple haze - these kinds of incident probably arise more often than some pilots/ATCOs would care to admit, and more often than the travelling public would wish to know. However there are a lot more close shaves now on the ground at airports than in the air, where movements are generally very well controlled and separation is maintained. Ground movements are not always radar controlled and in low visibility there have been many incidents and the occasional catastrophe, such as the SAS MD80 at Linate last year which hit the crossing twin and the Singapore Airlines 747 which construction plant when taking off on the wrong runway. Proper ground radar control would have prevented both these incidents.

[Standard Noise]

Sorry, don't agree, it's not Surface Movement Radar which prevents collisions, it's GOOD CONTROLLING! Having SMR doesn't make a better controller, but it can assist an ATCO in making/monitoring his/her decisions. There will come a time when it's not available and if you become too reliant on it, you'll come a cropper.

[FlyingForFun]

Out of interest...

...do you guys feel that part of the reason that "there are a lot more close shaves now on the ground at airports than in the air" (no idea where phd got this from, but it sounds sensible) is because vertical separation in the air means that if someone does screw up and put a plane in the wrong place, there's less chance of someone else being in that place already? I.e. the "big sky" theory.

FFF
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[purple haze]

my apologies to the spelling police, didnt know they were still on duty.

others, thank you for your answers and corrections on facts.

PH