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-   -   Oops! AAL B738 hits light pole at DFW (https://www.pprune.org/rumours-news/640801-oops-aal-b738-hits-light-pole-dfw.html)

spekesoftly 2nd Jun 2021 11:13

And what, please, is that dashed black/yellow line that lies across the intended path of the aircraft?
Probably an Intermediate Apron/Ramp Holding Point/Position.

DaveReidUK 2nd Jun 2021 12:08


"Edit: FR24 shows the location. A 2-aircraft remote stand opposite A-29 at Terminal A."

Yes, I believe the aircraft had pushed back from A29, having arrived at that gate about an hour and a half previously from KBNA.

FullWings 2nd Jun 2021 12:36

Assuming that they didn’t do it on purpose, it will be interesting to read what sent them down that route.

I suspect following the wrong markings could be high up the list. How many experienced pilots can put their hands on their hearts and say they’ve never started off down the wrong line, or even just changed their minds as to what appeared to be the correct option before committing to it? At the same time, it does seem to be a rather prominent obstacle but it might have looked different from cockpit level - lost in visual clutter, maybe?

teej013 2nd Jun 2021 17:56

The lines used to have other lines painted at 90 degrees to them, but have faded.

Less Hair 2nd Jun 2021 18:09

That's a proper marking not that faded guess line.

Pistonprop 2nd Jun 2021 18:40

Since it's not a very recent picture, I would say that it doesn't represent the state of those lines now. [You can clearly see that it's an AAL MD-80. They retired the last ones in September 2019].

Kirks gusset 2nd Jun 2021 19:42

Originally Posted by Dave Gittins (Post 11055213)
So where were the taxiway markings he should have been following ?

At a guess I would say that would be the marks on the concrete whilst maintaining situational awareness and trying not to hit anything! and for those that say they are "faded" must never have taxied at airports in winter conditions when frost and snow obscures them.

Equivocal 2nd Jun 2021 19:45

The most recent imagery available on Google Earth Pro is from 11/2020. There are clearly some places where old markings have been scrabbled off off the pavement but the current markings do appear largely to meet the the standards that one might expect at a major airport. In particular the the 'taxiway' centreline markings and intermediate holding positions are on a black painted background to enhance contrast between the concrete pavement and the makings and, hence, improve conspicuity. The edge markings on the apron appear rather less well maintained than the centreline and it is noticeable that the clarity of the edge/shoulder marking on the taxiway adjoining the apron at that junction appears far better than on the apron. This might be important because, if the incident aircraft was following any markings as the centreline guidance, it appears to have followed the edge markings. Apron markings around the world do vary but the US AIM suggests that the edge marking is a double line (either solid or dashed) whereas the true taxiway centreline is a single line (which is pretty much universal). It's hard to tell from the Google Earth imagery whether the edge markings are solid or dashed but there is a hint that they are, in fact, dashed.

Is it easy to mistake a pair of 6 inch wide, possibly dashed, lines for a single solid line? I guess on a dark and stormy night that might be a possibility, maybe even likely if some of the markings are worn....but these were rather different conditions. There are, of course, a variety of other reasons that may result in the pilot steering the aircraft mistaking the two types of marking. Judging by the rate of the turn (as well as normal practise) the aircraft was being steered with the tiller so, presumably, the pilot in the LH seat will be the centre of any investigations.

Just returning to the markings for a moment, the older imagery from teej013 shows the perpendicular edge/shoulder markings which are specifically intended to indicate which side of the pavement for aircraft use and which side is unusable by aircraft. Looking at the most recent imagery, these markings are well and truly absent. A shame really because it might have helped to avoid a rather unfortunate and undesirable incident.

There endeth the beginning of an armchair investigation seeking to identify possible contributory causes/factors. And apologies to the professionals if I've got anything wrong - full disclosure, I'm not a professional pilot and it's a good while since I was up the front of a B737.

PJD1 2nd Jun 2021 19:48


Not quite a pilot's eye view but perhaps this puts some perspective on it. Google says image data for this is from 2021

JH870 3rd Jun 2021 14:46

Originally Posted by Deepinsider (Post 11055727)
All aviators will be so sad watching this clip.It's just lazy dumb ass complacency driving around like that.Definitely change of seats at a minimum

I'd imagine most aviators would probably think, if it can happen to them, it can happen to me, after the year and a half of low to zero hours flying.

That you would call for a demotion or worse shows a lack of regard for human error, and frankly a lack of common sense.

:mad: happens 👍

Avman 3rd Jun 2021 15:57

Personally I'm always interested in the "why" rather than promoting punishment. What made a qualified Captain make this error? Were they pushed back to an unusual position which may have played a part? Were they in a hurry? Was there some unforeseen distraction in the cockpit?

B888 3rd Jun 2021 16:42

Not trying to judge here ( as the longer you’re a pilot, then you should realize how easy crap happens), but taxiway lines does not guarantee wingtip clearance. If you’re not absolutely sure, stop.
Other Airplanes may not be parked properly.

DaveReidUK 3rd Jun 2021 17:38

See the photo in post #29.

The taxiway onto which the 737 was turning (leading to Kilo, Lima and the runways) is 200 feet wide (between the edge markings) and has not one, but 3, parallel taxiway lines which allow two narrow-bodies to pass each other safely, provided each keeps to its own side of the taxiway.

It seems likely that the unfortunate combination of the "keep left" imperative and the ambiguous edge markings led to inadvertently following the LH edge marking line while thinking that it was one of the 3 prescribed taxiway lines.

Raffles S.A. 3rd Jun 2021 18:09

From previous experience, in places like Pointe Noire (very congested at times) when in a tight situation I opened my window and stuck my head out, and if in doubt, got a wingman.

I was also at Harare once and a BA 747 called the tower and complained that if they hadn't had a wingman, they would have collided with a parked plane even though they were following the taxi line. I certainly don't trust taxi markings in the third world but one would expect them to provide clearance in developed countries.

tdracer 4th Jun 2021 03:07

Watching the video, shortly after the aircraft hits the pole, something appears to fall off the right wing of the aircraft, outboard of the engine. Any idea what that might have been?

HighSpeedAluminum 4th Jun 2021 03:19

if you observe the top of the lamp post at impact you’ll have your answer.

Bksmithca 4th Jun 2021 03:24

Tdracer it's the top of the light that flew off and hit the top right side of the fuselage and slid down.

tdracer 4th Jun 2021 04:18

OK, thanks - missed that part on the first watch....

Lookleft 4th Jun 2021 06:13

It seems likely that the unfortunate combination of the "keep left" imperative and the ambiguous edge markings led to inadvertently following the LH edge marking line while thinking that it was one of the 3 prescribed taxiway lines.
Thats a very good place to start. Why would you even paint a line that looked like a taxi line that wasn't meant to be followed by an aircraft? Unfortunately for the crew they are considered to be the last line of defense and will bear ultimately responsibility for the accident.

BraceBrace 4th Jun 2021 09:37

Originally Posted by DaveReidUK (Post 11055641)
Still I wouldn't bet my house that I couldn't do something similar :-/

Yup... I "escaped" a couple of months ago entering an appron with a taxiway that had been "re-routed" with an S-bend and a mobile lightpole erected on the edge of the "old" taxiway. Any taxiway that is "indicated" by a set of lines on a big concrete sea is prone to error...

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