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ATCFloripa
15th Apr 2011, 00:24
Hi there, I'm an air traffic controller for almost three decades and I am always concerned about safety, I am very serious about that.

I think a good way to avoid misunderstandings among the international community of pilots and air traffic controllers, could be creating and disseminating the examples collected in some sort of data bank.
It is much easier to learn from what happened to others than trying to imagine what could cause a possible misunderstanding. I have noticed that pilots tend to understand and do what they need to do and I believe that it is easier to retain the last words from what we hear, sometimes ignoring unintentionally part of what was said in a whole sentence.

What I mean to say is: let's use these forums to exchange our experience and knowledge to improve everyone's safety.

An example: in Brazil, there is an Airline named GOL, we do not pronounce the final L as "L", instead, the final L is pronounced like "U", therefor GOL sounds exactly like "go."
Of course we all know that no one is supposed to cross a runway without listening to an [U]unambiguous instruction,, but again, when the cockpit crew is dealing with the checklist, it might be possible that they could understand that they are "cleared to cross" or "cleared into position" by the way, I believe the expression "holding position" should be prohibited because, due to the similarity to the expression "cleared into position", a little noise in the transmission could cause a runway incursion.

I would like to encourage everyone to participate with stories of misunderstandings that happened or situations one heard about.
A few minutes spent here could help us preventing dangerous situations. Thank you.

chevvron
15th Apr 2011, 09:54
The major ATC provider in the UK (NATS) runs a 'Communication Errors Working Group' to discuss and mitigate this type of thing.

rymle
17th Apr 2011, 18:49
I believe the expression "holding position" should be prohibited because, due to the similarity to the expression "cleared into position", a little noise in the transmission could cause a runway incursion.

Even better, scratch "cleared into position" and use "line-up and wait" instead (=

Tarq57
18th Apr 2011, 03:59
Wouldn't be too often you'd need to use the "and wait" component of that instruction on ice runway, would it? :E

hoaiphuongNgo
18th Apr 2011, 07:25
Thanks ATCFloripa!Your topic is quite interesting to me.I'm TWR controller at a small domestic(non_radar) airport in VietNam.My English is not very well,so I try to follow the Radio telephony(ICAO),but sometimes it still makes us confused.
Once,I cleared an A320 to line up RWY to be ready for immediate departure,due to another landing traffic expected to be on long final in 2 minutes(VOR/DME approach);
I said:"HVN ABC,line up runway",
he readback:"line up and wait"(Oh my God!)
I said again:"line up runway for immediate departure,report ready" ;
he readback(and moved ahead to line up):"line up RWY,stand by for taking off";
I asked him:"Are you ready for immediate departure?";
he answered:"stand by,I call you back"(at that time he lined up already);:ugh:
I said:"We will have landing traffic on final in 1 minute.If you're unable for immediate departure,vacate the RWY";
he answered quickly:"ok ok we're ready"...
In the situation above,we got "misunderstand"between the phrase"LINE UP RUNWAY" and"LINE UP AND WAIT",that somehow causes the difficulty for controlling aircraft.

p/s:according to the law of non_radar airport(small domestic airport in VietNam),a departure aircraft is not permitted to take off if an landing aircraft is on final.

samotnik
18th Apr 2011, 10:32
hoaiphuongNgo, that's why you should include runway designator and say 'line up runway XX' or 'line up runway XX and wait'. It's much less confusing, especially when you far-east guys pronounce 'runway' and 'and wait' in a very similar way... :)

rymle
18th Apr 2011, 13:18
p/s:according to the law of non_radar airport(small domestic airport in VietNam),a departure aircraft is not permitted to take off if an landing aircraft is on final.

With the risk of sounding like a wiseguy in this thread:

These kind of operational rules makes it even more important to make sure that the crew is ready (and even better, that they are informed of the traffic situation), for instance by asking them while taxiing:
"Arrival 12 miles out, are you ready for an immediate departure?"
(affirm)
"Line up runway xx, expect immediate/rolling departue" / "Cleared immediate take-off"

In my part of the world, the meaning in the difference in phrase for line-up is commonly known, at least by national pilots:
"Line-up runway xx" = You can expect take-off clearance before you have stopped in position
"Line-up and wait runway xx" = There might be a short delay in position