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Old 15th Mar 2004, 10:57
  #19 (permalink)  
LostThePicture
 
Join Date: May 2003
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If not, I understand that Aeroflot have a vacancy on their cross-Swiss route.
Not the most appropriate (or accurate) sentiment to finish with, but otherwise a topic that should be of interest and concern to pilots and ATCOs everywhere, in the light of recent events.

I'm in agreement with 5milesbaby that the pilot should receive a severe reprimand for his actions. TCAS is there to help pilots prevent a collision with another aircraft, and used properly (ie following the verbal instructions in an RA situation) it works superbly.

The TA warning is solely there to prepare pilots should the situation deteriorate to the extent that an RA is required to resolve it. Generally, there's a 15 second gap to allow the crew to try to acquire the traffic visually (if in VMC). An RA gives (or should give) BOTH pilots involved a 30 second interval to take appropriate VERTICAL avoiding action before a collision occurs. If the ATCO also realises that a loss of separation is imminent, then s/he should also provide avoiding action - best practice is to give TURNS to complement the vertical solution provided by TCAS.

So there should be no lateral avoiding action unless provided by ATC. Simple as that. A pilot taking horizontal separation into his own hands risks an airmiss with other traffic, especially in a busy terminal environment where such traffic could be on a parallel heading as little as 3 miles away.

I suspect the female controller in the EZY4DD incident went through a range of emotions after the unnecessary actions of the pilot and the unnecessary tirade that followed. Doubt, fear, and probably later on a dash of anger. I know I'd have been furious if a pilot had done that to me.

Kite - if you find yourself in such a situation and you want to reduce your climb rate to 500ft per minute, feel free. Those would be the actions of an intelligent pilot who doesn't want to get involved in a nuisance RA situation. Trained ATCOs make very few mistakes (believe it or not) and the traffic you see is probably going to pass 1000ft above you. Of course, if the frequency is busy, the ATCO may not have time to call the traffic to you. However, if at all possible, the ATCO should pass traffic and reiterate the cleared level: "c/s, maintain FLxxx upon reaching, traffic in your 1 o'clock, 12 miles, crossing right to left, 1000ft above". Pilots from certain carriers will acknowledge the traffic info - "Roger, got him on TCAS", and then, instead of levelling off at a nice gentle 500fpm, proceed to climb/descend towards the traffic at the fastest possible rate. So, 15 seconds later: "London, c/s - TCAS descent". Honestly, it happens all the time. It would be laughable if it wasn't so annoying. Do pilots get some sort of bizarre kudos for flying their aircraft into the maximum number of nuisance RA situations?

LTP


One last thing:
Presumably this is a reference to the Bassersdorf, Switzerland accident in 2002.
WHBM, presumably not. More likely to be a reference to Uberlingen, which is in Germany. The Bassersdorf accident, in 2001, involved a single Crossair aircraft in what appears to have been CFIT. See this thread.
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