Midway MDW incident averted
 

Flight numbers 1328 and 3828, hmmm.

call signs too close
 

the call signs are too close. but an interesting read, thanks for posting.

And they way they say it, thirteen-twenty-eight and thirty-eight-twenty-eight. Hmm indeed! The pace of ops at MDW can get such that people start stepping on each others radio transmissions all too often. Is it possible that an airline pilot has to concentrate on the flight number since it changes all the time and since the company call sign is always the same, maybe some don't even hear it?

Whatever the reason, it's a cheap lesson for everyone.

yes, and if we said: Flight WUN THUREE TWO EIGHT instead of thirteen twenty eight

hmmmmm

Definitely not the first time similar sounding call signs have resulted in pilots executing someone else's clearance. There isn't a surefire solution to every problem, but this one requires more attention to detect than many other problems do. In my experience, ATC is usually really on the ball about issuing warnings for similar sounding call signs on the frequency, but nobody can be expected to recognize it every time. Perhaps it IS time to require all call signs to be spoken alphanumerically one character at a time. That would take some time for pilots and controllers to get used to. Seems worth talking about at least...

i have never understood why the FAA has not adopted the EU system of callsign modification, e.g. SWA1328 could have used the callsign SWA132H and SWA3828 could have used the callsign SWA382J. Risk reduced. I loved the callsign mod when I flew contract in Europe.:ok:

Takes more readback brain power to say each digit seperately. That increases the chance of error. The letter at the end is better.

Really, works well all over the world, except in the USA. Does your statement describe the underlying problem?

US lets you modify your call sign at will. Try It !

Reading each digit separately or using letters is no guarantee either. I've had very similar and even identical callsigns of different airlines on the same frequency. One time an altitude bust was marginally avoided by an attentive controller. Perhaps if the system was a bit smarter and could update callsigns in real time when two similar sounding callsigns are about to enter the same sector.

Both the ground and tower conversations are already up on LiveATC.

Before pushing back, these two flights stepped on each other's transmissions to ground. That's a clue. While still on ground frequency, ATC directly advised both flights of the similar numbers on the frequency. Both flights acknowledged.

Delta somehow started rolling even thought the takeoff clearance was for 31C and he was on 4R. I Wonder if the Delta crew every heard of a pilot named van Zanten?

Herald and jacdec got the story

"garbled transmissions"...could have been a reiteration of Tenerife. What if there was fog at the time ?

http://www.jacdec.de/WP/wp-content/u...MDW_MAP_sm.jpg

Good point, and while we're at it, why doesn't the FAA try to stamp out the use of slang?

"Southwest thirteen twenty-eight" and "...checking in three five oh" and "runway four" might sound cool on the radio, but it's not ICAO standard and has huge potential for a serious accident.

Oh, but don't forget to add "heavy" to your call sign when taxiing or cruising at FL370... :ugh:

Wonder how often this occurs. On a visit to West Palm observed an exact same event, with a Shorts 360 and Gulfstream. Both stopped prior to the intersection.

Actually, most SWA crews use pretty good ICAO phraseology when they fly to the Caribbean. It's just a domestic thing, I guess.

I wouldn't go as far as calling it a huge potential for a serious accident. There is never just one factor leading to an incident/accident.

The example you gave is correct in the US, group form for the callsign.

Like usual it did not take long for the radio pedants to ride in with their self righteous certainty about the superiority of the EU way. :ugh:

The new hires at Southwest and Delta are running 4 and 5 thousand hours, but your EU LOCO with the 200 hr airline puppy mill graduate is going to be so much safer because he can talk the "right" way on the radio :rolleyes:

the group form of call sign has been around for awhile.

now,some smart computer programmer should come up with a way of assigning call signs to make sure there are no confusing elements.

Am I the only one who thinks that, having been cautioned about the similar flight numbers, having actually stepped on each other which getting push-backs approved, and knowing departures were on both 31C and 4L, that the Delta pilot should have figured out that even if the flight number sounded close, he wasn't on 31C?

We've heard/read from the ATC side of the incident. Excerpt from Aviation Herald.



The CVRs may lend additional information to see if there was non essential conversation taking place which could have also contributed to the incident. Not the first incident/accident that resulted because of poor cockpit discipline during critical phases of flight.

Common flight numbers? EK325 and 9W325 DXB - MAA a red eye flight on the heals of one another. Issues... language barrier... backside of the clock flying... ATC/Flt crew RT mistakes. Letter prefixes or suffixes don't cure the problem.

It's called the "my poo doesn't stink" syndrome! Proper R/T fixes all the aviation problems, like lag of piloting skills, underpaid LCC pilots etc.*

* sarcasm

What really caused this incident is trying to put 7 pounds of sugar into a 6 pound sack. And the need for speed. Hurry up all you pilots or the chief pilot will get mad at you for being late.

IF you are on the ground, the need for speed STOPS. Parallels to Teneriefe are about right. WAS there any question in the cockpit? IF SO, don't move, clarify the clearance.

Get on the radio and confirm: Tower, DELTA XXXX VERIFY takeoff clearance for DELTA XXXX on runway XX.

Midway airport is a funny airport. Its operations are dictated more by nearby o'hare airport than its own needs. Add to that performance limited runways and things are hanging on by a thread.

Its hard to see what is going on , on the other runways with the mk1 eyeball too.

Well, it worked out and it was interesting to hear old Southwest cover themselves first.

I can imagine a scenario in which the radio calls were covered just enough to make sense to both planes/pilots

As an ex air trafficker in a very distant previous life I still recall the numbers wun, too, tree, fower, fife, ate, niner etc. ... Could never add two numbers together to make thirteen (wuntree) or similar.

When recording the ATIS the QFE might be 1000mb but I used to have to record "wun zero zero zero" although I would bend the rules ad-libbing "one thousand" millibars.

And of course the lower runway numbers were "zero nine" or similar, always the zero.

But not in the USA.

FAA AC 150/5340-1L:

"A single-digit runway landing designation number is never preceded by a zero"


https://s3.amazonaws.com/classconnec...CD5257C356.jpg

I've always thought group callsigns were an accident waiting to happen. 13 sounds very much like 38 when spoken as a group callsign. I have heard of incidents involving for example 59 vs 69 or 15 vs 16 which sound very similar when using group callsigns.

The whole point of the phonetic alphabet designed by our forefathers was to avoid this.

I think I'd do the same thing these days, it would be good to know before calling the company.

And, if you said that the Delta Professionals had made a mistake, who would believe you without a corroborating witness?

Remember the not so distant 'good old days' when you might try a couple of takeoffs before taxiing back to the blocks with a configuration warning you were 'sure' was spurious? Now, you need to be redispatched if you've pushed the throttles up, released the brakes, started to roll and been told by the tower to stop and taxi clear of the active runway for flow control.

At least that is how I understand it, the goalposts keep moving on when you need an amended release, when you can enter an MEL item yourself, defer the deferral, and so on.

So yes, I spend a lot of time thinking about CYA stuff instead of flying the plane.

There is an audio link in this WSJ blog article where a Southwest pilot is similarly anxious to make sure the tower controller gets full credit for an earlier near miss on the ground at MDW:

Audio Recording of Midway Near-Miss Paints Picture of Southwest Pilot Concern - The Middle Seat Terminal - WSJ

airbubba, believe me I understand.


The whole thing has been ginned down to the minimum, with no reserve for failure.

Radio calls 70 years ago were precious things and each word had to mean something. War and Life depended upon it.

The poster who mentions the older methods on the radio is correct (notice I didn't say RIGHT, which should be a direction!).

Even years ago, aviation radio started to sound like, C B RADIO LINGO!

Slow down, do it CORRECTLY, read the AIM and do it like it says and BE SURE

I get the possible confusion between 1328 and 3828, and the possibility of an incomplete (stepped-on) reception....

But if you are flying for DELTA, and the clearance is given for SOUTHWEST, surely anyone will notice that difference? I mean, that is EIGHT different letters (preceding), not just one (trailing, as recommended from European ops).

I've sure made the CB observation as well. It goes over even worse internationally when we Americans try to sound 'cool'.

From a 2011 post here on a similar clearance miscue thread, about a radio exchange I heard in Singapore:

http://www.pprune.org/rumours-news/4...ml#post6837505

They did
 

Used to, but I think it was an idea from the airline's safety dept, not The Friendly Aviation Agency.

Back in the 60s/70s when Air West was flying, every AW call sign ended in "Red" to avoid confusion with Western Airlines flights. It would have been "Western thirteen twenty eight" and "Air West thirty eight twenty eight Red."

Yes really. I'm not saying it's correct but "thirty eight, twenty eight" is easier than "three-eight-two-eight" when issuing or reading back multiple instructions and that's why pilots and controllers revert to it.

It reduces the memory involved by compartmentalizing two numbers instead of four. Push one glass on a full coffee table and another is more likely to fall off. It works...just a question of what's the safest overall. Pilots and controllers in the U.S. know it works from experience with both, especially with 4 digit call signs.

What where they using in the Canary Islands?

It would be interesting to find out the background details about each crew's duty day up to that point.

An error was made, which, in isolation looks like it may have been due to carelessness. Were the crews at the end of a 12 hour day?, were they at the end of a series of long duty days.

Just saying!

However, removing one factor from the chain of events may be all that is needed to prevent the incident/accident occurring.

There are of course numerous factors which can lead to these type of incidents. Some contributing factors are possibly:

- use of non ICAO phraseology (the norm in the USA though).

- Over rapid delivery of clearances by controllers.

- A tendency to clip the first part of the call sign when initiating a transmission.

These busy U.S. airports have to move a lot of traffic. In their endeavour to keep things moving, many controllers resolve to speaking much faster than they in fact really need to. Couple that with the additional traffic information they have to reel off prior to giving what should be a relatively simple take-off or landing clearance and you have a recipe for misunderstandings.

Do your generalizations have anything to do with the MDW event?

Why don't we wait for the professionals whose job it is to investigate figure it out.

Take a chill pill West Coast. I think you may have misunderstood and gone on the defensive. I think ATC in the USA is some of the best in the world. What I wrote are generalizations of my own observations from personal experience and the witnessing of a few "close calls" over many years working in ATC. I'm not aware that I said this was the cause for the MDW incident. When I said, " some contributing factors are possibly" I was referring to my first line and not specifically to the MDW incident. But on reflection I can now see that I should have made that somewhat clearer. Oh, and note the word "possibly".

Which would only be made worse with ICAO one digit at a time call signs, such as Tenerife where KLM received a four number call sign, a new departure clearance with altitudes, fixes and radials......all in a single transmission with the words "cleared" and "takeoff" while he was assigned line up and wait.

Would a two or three digit flight number (or phraseology which compartmentalized it to such) have made the difference? Maybe not, but it would have made the odds better.

Even the controller....one digit at a time and then "uh"

Looking at the amount of daily flights in the USA and the use of non-ICAO phraseology, I think the this whole proper R/T ICAO pet argument is grossly exaggerated.

I agree that especially SWA should use less slang domestically.

I disagree that reading back single numbers are much safer than read in chunks, the system of using different letters as suffixes seems to be best solution.

Plainly speaking
 

Quote Phileas Fogg:As an ex air trafficker in a very distant previous life I still recall the numbers wun, too, tree, fower, fife, ate, niner etc. ...

Just musing-My Black Country mates and I were almost there anyway!