Close call at MDW - not sure if it's already been posted here

Nice job by the local controllers. Probably saved hundreds of lives.
 
If you haven't listened to the recording on the LiveATC.net site, you really need to.

This a perfect example of how a busy radio environment combined with sloppy radio technique and expectation bias can dang near kill a whole ton of people. And I would submit that the mistake that the Delta crew made could happen to just about anybody.

http://www.liveatc.net/recordings.php

I believe you need a login account to actually listen, but it is free.
 
Yep, it can happen to anybody. I've mistakenly taken instructions intended for another aircraft, but fortunately it's never been at such a critical point. It's definitely a good reminder for everyone.
 
Thank God nobody was hurt. Good job to the controller for catching it before disaster. Mr. Delta is gonna have some splainin' to do.
 
I think part of the problem is that controllers often mangle our call sign, so we become used to being referred to by a similar sounding, though not exactly correct, name.
This "practical tolerance", coupled with some static or interference, can sometimes become very dangerous, as in the case in point.
 
Sounded like the DAL transmissions started after, and ended before SWA's.
That means neither controller nor SWA would have heard any part of what DAL said.
DAL might have heard the start or end of SWA's (but might not know what they were responding to).
I think the controller heard, and registered that SWAs readback was partially blocked, maybe that cued him to visually check on what DAL was doing.
 
Fearless Tower said:
This a perfect example of how a busy radio environment combined with sloppy radio technique and expectation bias can dang near kill a whole ton of people. And I would submit that the mistake that the Delta crew made could happen to just about anybody.

http://www.liveatc.net/recordings.php
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Disagree. When you're sitting in runway 4 and the controller clearly says "cleared for takeoff runway three one center", there is no excuse.
 
Ron Levy said:
Disagree. When you're sitting in runway 4 and the controller clearly says "cleared for takeoff runway three one center", there is no excuse.
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You are correct. The 31C was the key part that the two pilots in the Delta cockpit missed.

But you missed my point about expectation bias.....or do you think you are immune, oh great one?
 
Fearless Tower said:
You are correct. The 31C was the key part that the two pilots in the Delta cockpit missed.

But you missed my point about expectation bias.....or do you think you are immune, oh great one?
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Expectation bias is an explanation, but not an excuse for a major air carrier crew. At that level, such errors are unacceptable.

OTOH, the controller's actions were exemplary. I can only imagine what went through his mind when he heard the heterodyning of the two crew replying at once to his transmission, and he reacted promptly and effectively.
 
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Ron Levy said:
Expectation bias is an explanation, but not an excuse for a major air carrier crew. At that level, such errors are unacceptable.

OTOH, the controller's actions were exemplary. I can only imagine what went through his mind when he heard the heterodyning of the two crew replying at once to his transmission, and he reacted promptly and effectively.
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An error like that is always unacceptable, not just for a professional crew. That said, people are human and mistakes of that magnitude will be made again regardless of any safeguards.

It still doesn't excuse what happened, but it is the reason for it.
 
Let'sgoflying! said:
I'd like to hear the cvr, see if it was indeed sterile.
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Lots of emotional stuff going on with the Delta pilot group at the moment, but hopefully these guys kept it tight. I'm sure we'll find out.
 
Fearless Tower said:
You are correct. The 31C was the key part that the two pilots in the Delta cockpit missed.

But you missed my point about expectation bias.....or do you think you are immune, oh great one?
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Ron Levy said:
Expectation bias is an explanation, but not an excuse for a major air carrier crew. At that level, such errors are unacceptable.

OTOH, the controller's actions were exemplary. I can only imagine what went through his mind when he heard the heterodyning of the two crew replying at once to his transmission, and he reacted promptly and effectively.
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Kritchlow said:
An error like that is always unacceptable, not just for a professional crew. That said, people are human and mistakes of that magnitude will be made again regardless of any safeguards.

It still doesn't excuse what happened, but it is the reason for it.
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Let'sgoflying! said:
I'd like to hear the cvr, see if it was indeed sterile.
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kayoh190 said:
Lots of emotional stuff going on with the Delta pilot group at the moment, but hopefully these guys kept it tight. I'm sure we'll find out.
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This is why human factors has become so prevalent in accident/incident investigations. Also why air carriers have adopted a "just culture" to deal with such events. We are all human, we all make mistakes (even Ron L) so it's best we identify the cause, assess the risk, mitigate the risk and learn from it without fear of repercussion.
 
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And my wondering about the cvr contents was not because I am judgmental pr. --- I feel for all those guys and am fully aware that this, or some other oops awaits me tomorrow. I want to know about the cvr, just to see if it was a factor.
(I sort of hope it was a nonsterile cockpit, as that is a known issue and easier to deal with than yet another huge FAA study and rule imposition on pilots for some new issue.)
 
RotorAndWing said:
This is why human factors has become so prevelant in accident/incident investigations. Also why air carriers have adopted a "just culture" to deal with such events. We are all human, we all make mistakes (even Ron L) so it's best we identify the cause, assess the risk, mitigate the risk and learn from it without fear of repercussion.
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Big proponent of "just culture" here. It has helped our industry in huge ways, and I hope the powers that be ensure it stays long enough to become engrained in everything we do.
 
Similar sounding 4 digit flight numbers was identified as one of the 2013 ATO Top 5 issues contributing to risk in the NAS. They are much easier to hear the cadence and make a mistake the call sign. 13 and 38 are very dissimilar. But the cadence of the 4 digits ending in 28 makes the brain interpret them as similar. With the advent of regional carriers and more flights, 4 digit call signs have proliferated.
 
John Collins said:
Similar sounding 4 digit flight numbers was identified as one of the 2013 ATO Top 5 issues contributing to risk in the NAS. They are much easier to hear the cadence and make a mistake the call sign. 13 and 38 are very dissimilar. But the cadence of the 4 digits ending in 28 makes the brain interpret them as similar. With the advent of regional carriers and more flights, 4 digit call signs have proliferated.
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I can't think of a single flight over one hour when my call sign doesn't get mangled at least once by a controller. I generally correct them, and they are generally thankful, but in high workload environments you can sense their frustration/annoyance. The end result, as I noted above, is that over time your ears get used to hearing your approximate call sign all too often. Of course relying on "approximation" for critical things like takeoff or landing may be detrimental to your health. :hairraise:
 
RotorDude said:
I can't think of a single flight over one hour when my call sign doesn't get mangled at least once by a controller. I generally correct them, and they are generally thankful, but in high workload environments you can sense their frustration/annoyance. The end result, as I noted above, is that over time your ears get used to hearing your approximate call sign all too often. Of course relying on "approximation" for critical things like takeoff or landing may be detrimental to your health. :hairraise:
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I can't think of a single flight at my company I've been on where some ATC'er doesn't get our callsign right. I'll try to correct them (by slowing down and very clearly stating the callsign) and they don't seem to catch on.
 
KSCessnaDriver said:
I can't think of a single flight at my company I've been on where some ATC'er doesn't get our callsign right. I'll try to correct them (by slowing down and very clearly stating the callsign) and they don't seem to catch on.
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Are you talking about the word part of a callsign? I know I flew around for a long time before I finally figured out they were saying "Air Spur". If you were a controller you might have more of a clue, though. Our ending two letters are often botched. They are either reversed or the ending U is read as a J or an A. I can understand the J but what about the A?
 
Ron Levy said:
What part of "Southwest" sounds like "Delta", and what part of "three one center" sounds like "four"?
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I think the "cleared for takeoff" part sounded familiar. :eek:
 
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Everskyward said:
Are you talking about the word part of a callsign? I know I flew around for a long time before I finally figured out they were saying "Air Spur". If you were a controller you might have more of a clue, though. Our ending two letters are often botched. They are either reversed or the ending U is read as a J or an A. I can understand the J but what about the A?
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Yeah the word part. Close to home, it's not bad, they see us enough. But the further we get from base, it gets bad.
 
Fearless Tower said:
If you haven't listened to the recording on the LiveATC.net site, you really need to.

This a perfect example of how a busy radio environment combined with sloppy radio technique and expectation bias can dang near kill a whole ton of people. And I would submit that the mistake that the Delta crew made could happen to just about anybody.

http://www.liveatc.net/recordings.php

I believe you need a login account to actually listen, but it is free.
Click to expand...

FYI for those who click:

*the top link is ground (by BradG), including specifically advising both flights of the similar call signs

*the second link is tower (topgun966), action starts at around 1:15
 
RotorDude said:
I think the "cleared for takeoff" part sounded familiar. :eek:
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I think you're right. But given the FAA's response to the mess at National a few years back when Approach was still arriving south and Tower started departing north, I suspect this event may lead the FAA to consider banning simultaneous "line up and wait" on intersecting runways.
 
Ron Levy said:
What part of "Southwest" sounds like "Delta", and what part of "three one center" sounds like "four"?
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When he first gives the takeoff clearance, all you hear on the tape is "28, fly heading....etc" IOW, he was talking as he keyed the mic, so the airline part was omitted. There was no airline mentioned (in the transmission) on the original clearance.

The Delta guys heard the 28, missed the 31C embedded in the center and thought (incorrectly) that the clearance was for them and at that point the assumption was so strong that when the controller did try to clear up the blocked signal and used "Southwest", the Delta guys went into mind block and kept stepping on SWA.

Back to my point in my original post on this thread, this is not an 'excusing' point (as you incorrectly inferred), but an important learning/teaching point.
 
Listening to that recording I agree this could easily happen to anyone. Yes, the Delta pilot responded to the wrong call sign but this happens multiple times a day every day. I've responded to the wrong tail number too. That is why you read back and confirm then ATC will correct you. The Delta pilot did that, he read back the clearance. Unfortunately for him it was blocked by the other pilot. Twice. Major bummer.
 
Fearless Tower said:
When he first gives the takeoff clearance, all you hear on the tape is "28, fly heading....etc" IOW, he was talking as he keyed the mic, so the airline part was omitted. There was no airline mentioned (in the transmission) on the original clearance.
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As pointed out elsewhere, LiveATC is scanner-based and clips the first bit of each transmission. Other sources suggest the controller used the full call sign.
 
There are definitely limitations to LiveATC. The only time I tried to find a clip was when we were issued a last minute go-around. The go-around was not recorded, only my flying buddy asking why we got the "wave-off". I guess he was so surprised he reverted to military terminology.
 
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