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Comment by anovikov | Hacker News Reader

This is facilitated by the fact that in some airports, taxiways and runways are similar and sometimes even used interchangeably (!), i.e. a runway may be remarked as taxiway and vice versa. So it's not 'how can he be so dumb' moment, in some case you have no way to tell the difference unless you just know.

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Yeowch. I was about ready to make a comment about how the airport/approach plates should make something like this impossible, but then I looked up the diagram for SEA:

https://flightaware.com/resources/airport/SEA/APD/AIRPORT+DI...

Basically, you've got a runway, the taxiway of the same length as the runway!, and then two longer runways from left to right. I totally see how someone could make this mistake in bad lighting or weather!

And a note on that diagram:

    CAUTION:
    Pilots are cautioned not to
    mistake Twy T for a landing
    surface.

It feels like it could be solved incredibly easily by a row of lights at the beginning/end of both the taxiway and the runway, bright red for taxiway, bright green for the runway. If you are attempting to land on the strip marked red, then you are doing something wrong. In case that the taxiway is legitimately used for landing, change the colours around.

I guess it hasn't been done for "reasons", I'd be quite interested in hearing why.

this sounds like the start of a good idea, but we should choose something that works for colorblind people and red/green colorblind people too.

Stupid question - can you be certified as a commercial pilot if you are colourblind?

You can’t even be certificated as a Private Pilot if you are colorblind.

Not true at all.

https://www.aopa.org/go-fly/medical-resources/health-conditi...

My father is red-green colorblind and he flies small planes.

You can, but you're not allowed to fly at night.

Why do people comment on things they know nothing about? Of course you can.

It's HN.... I get a good laugh out of all these aviation related threads. Understandably your average CS undergrad doesn't have much real aeronautical knowledge but that doesn't stop everyone from blowing up the comments every time the word 'airplane' is uttered.

No you just get a night flying and color signals proscription on your certificate if you're a monochromat or dichromat (full color blindness); if you merely have a color discrimination problem by being an anomalous trichromat, you might pass the test, or fail it but then get an exemption (reversal of the prior failure) by later passing a more involve series of tests.

No, you can't. A friend of mine couldn't become a commercial pilot because he has some kind of colourblindness.

However, I remember him trying for some time and even campaigning for colourblind people to be admissible as commercial pilots because for the actual flying colourblindness doesn't seem to matter.

So, perhaps ridiculous as it may sound taking colourblindness into account when proposing such an improvement isn't such a weird idea after all.

You can become color blind later though.

Commercial pilots are generally required to take a regular medical (it's every 6 months or 12 months in the UK).

If a pilot were to acquire colour blindness, they'd be obliged to ground themselves and report the condition to the aviation authority.

Or temporarily from medication, particularly those used to treat erectile dysfunction and benign prostatic hyperplasia [1][2].

[1] https://www.faa.gov/about/office_org/headquarters_offices/av...

[2] https://www.leftseat.com/viagra.htm

... and as a professional pilot, you'd probably have to consult a flight physician if you were taking meds like these.

Actually, airline pilots (and pilots generally) are not the only people you need to take into account here. Many other potential users of the runways and taxiways would need to be taken into account, including ground staff and maintenance staff. Since I doubt that all of these are ruled out on the basis of colourblindness, it makes sense to construct a system that is impervious to ambiguity due to colourblindness.

But ground and maintenance staff don't need to identify them by colour from far away. For them, you could rely on simple signage.

Yes, but the certificate comes with a limitation (color signal landing daytime only proscription; or night and color signal landing proscription).

The requirements vary depending on class of medical certificate but in this context it's a class I medical for airline transport pilots (not commercial pilots) so it's complicated.

Also, full on dichromats or monochromats are rare. Usually people are one of three anomalous trichomats. Hence testing is required to determine if it's a problem. The initial test is designed to have a high failure rate, and the exception tests to get the restrictions lifted take more effort.

https://www.aopa.org/go-fly/medical-resources/health-conditi...

Not a stupid question at all. I clearly remember doing the colour blind test during my preliminary medical when I arrived at flying school to get my commercial licence.

The test consists of going through a book with images made up of different coloured dots, and within each image was a coloured number made up of similar dots. We simply had to flip through the book and identify the number within each image.

I was totally smug as I flipped through the book, calling out the numbers and watching the doctor tick off his chart. But towards the end of the booklet, I reached a page, and the image was just a jumble of dots to me. I couldn't see a number. I remember the panic and tightening in my chest as I thought to myself "Oh No, I can't see the number - I MUST be colour blind!! My dream of being a pilot is OVER".

I stared and stared at the page, but in the end had to concede defeat and I quietly told the doc that I couldn't see the number on that page. "Oh", he replied casually. "That's OK, there isn't one on that page!". And he grabbed the booklet and tossed it back on his desk saying "You passed."

It is done pretty much like that. PDF warning, page 31: https://www.faa.gov/airports/southern/airport_safety/part139...

Taxiways are marked with blue lights.

Here's a video of a night landing on the same runway, the approach lighting is unmistakable: https://www.youtube.com/watch?v=rNMtMYUGjnQ

Yeah. At 1:18 that's clearly HIRL enabled. There's no ambiguity that's for a runway rather than taxiway. And it's not possible to visually misalign yourself with the taxiway, the whole point of HIRL is a visual aid for precision instrument landings in bad weather for Cat I and II ILS landings. On an instrument landing, it's not legal to go below decision height (200 and 100 feet respectively) unless you meet the visual reference requirement in 91.175 c3, ergo the HIRL lighting is simply unambiguous for a night VFR landing, and makes me wonder if it was even on.

This already exists. Runway is lit up in white, has a green strip of lights at the close end as you look at it, and instrument rated fields have a chase strobe that points right to the end of the runway. Taxi ways are blue.

Things like this are being tried. SeaTac airport has a taxiway which is large, parallel, and frequently (enough) mistaken for a runway.

> SEA-TAC personnel have been very proactive in trying to reduce the problem, including the installation of an unlit, nonreflective elevated lighted X at the threshold of taxiway Tango; broadcasting a notice on the Automatic Terminal Information Service (ATIS) not to mistake the parallel taxiway for the adjacent runway; posting warnings on aeronautical charts not to mistake the taxiway for runway 16R; and the development of numerous training aids and brochures that explain the problem to transient pilots traveling through SEA-TAC.

(Testing of multiple methods begins on page 5)

http://www.airtech.tc.faa.gov/safety/downloads/TN07-54.pdf

"...including the installation of an unlit, nonreflective elevated lighted X at the threshold of taxiway Tango..."

Unlit lighted X. Right.

My assumption based on nothing in particular is that one (of unlit/lighted) means 'Lights contained within the X illuminating it from within' and the other means 'Lights external to the X illuminating it from without'

It’s SFO though. And he’s an airline captain, so he should know.

The absolutely stellar safety record of the airline industry exists because they have repeatedly and consistent pushed past human error as an explanation for a crash.

Understanding that if a human made this mistake, another future human will likely make the exact same mistake, they push to understand _why_ an airline captain that should know made this error. Then try to correct for that.

If every crash was written off as "the captain should have known better", aviation would not be nearly as safe as it is.

Someday, perhaps computer programmers will start applying this principle.

They do, or at least the big-scale places who know what they’re doing do. When Gmail or aws-east-1 or something goes down for hours, nobody is fired: they figure out why it was allowed to happen and change procedures so it can’t happen again.

Perhaps not all tech companies care to push past human error in each postmortem (or even have a proper formal process at all), but some are known to do just that. Etsy and Google are among the well-documented cases.

> This idea of digging deeper into the circumstance and environment that an engineer found themselves in is called looking for the “Second Story”. In Post-Mortem meetings, we want to find Second Stories to help understand what went wrong.

— Blameless PostMortems and a Just Culture,

https://codeascraft.com/2012/05/22/blameless-postmortems/

> Blameless postmortems are a tenet of SRE culture. … Blameless culture originated in the healthcare and avionics industries where mistakes can be fatal. These industries nurture an environment where every "mistake" is seen as an opportunity to strengthen the system. When postmortems shift from allocating blame to investigating the systematic reasons why an individual or team had incomplete or incorrect information, effective prevention plans can be put in place. You can’t "fix" people, but you can fix systems and processes to better support people making the right choices when designing and maintaining complex systems.

— Site Reliability Engineering — Postmortem Culture: Learning from Failure

https://landing.google.com/sre/book/chapters/postmortem-cult...

This was address very well by a video posted on the Piper Alpha story yesterday.

https://news.ycombinator.com/item?id=14732404

https://www.youtube.com/watch?v=S9h8MKG88_U

Amazon is pretty strong on this front too, the most recent public example is the S3 outage and postmortem[1].

>Unfortunately, one of the inputs to the command was entered incorrectly and a larger set of servers was removed than intended.... We have modified this tool to remove capacity more slowly and added safeguards to prevent capacity from being removed when it will take any subsystem below its minimum required capacity level. This will prevent an incorrect input from triggering a similar event in the future.

[1] https://aws.amazon.com/message/41926/

They do. That's what UX is all about. Not just UI, not just making thing possible or visual, but actually making the experience as smooth and frictionless as possible.

UX is the bane of usability (at least as practiced). E.g. We've had professional "UX" designers seriously contend that "cancel" buttons should be made to not look like buttons. The joke at a certain large company was that if the UX designers had their way every default button would be big and green and every other button would be invisible.

True usability is about helping people make the correct decision, not just being smooth and frictionless. (See Don Norman's classic example of fire escapes that send people into basements to be trapped.)

True. But as with any other discipline, it's about thinking about the intent and final goal, not just following a rule book containing arbitrary roles.

I'm a daily user of some of the most complicated engineering software on the market. Every single release promises "Easier to use!" but all they do is make the most basic beginner-level actions more prominent and hide all medium to advanced level important functionality behind 3 extra clicks.

The end result is a beginner can do a tutorial exercise in 20 minutes instead of 30, while any true day to day work in the software takes 4 hours instead of 2.

From the company's perspective, getting more beginner users on the software (and converting them to regularly paying users) is probably the priority.

That doesn't mean they couldn't put an "advanced mode" setting/option that makes the UI streamlined towards users like yourself, though.

Do you think this tradeoff between easy-to-start-using and power-use-friendly is intrinsic, a scale that designers need to choose where they want their software in it, or is it possible to hit both ends? Does anyone have examples of things they think address both beginners and power users adequately?

While I agree generally with that sentiment, there's a key difference.

Airplane pilots are licensed, certified, trained, and regulated. There's a clear floor to who is allowed in the cockpit (barring extreme emergencies, e.g., incapacitation of a pilot).

By contrast, software is made available to pretty much the entire world. And it turns out that two thirds of all adults have "poor", "below poor", or no computer skills at all. Which is to say, the qualifications floor is nonexistent.

If you're designing a one-size-fits-all system, you've got to design for this. The results, I'd argue, are ... not particularly satisfactory.

I'm not saying "don't design for the user in mind", or "don't dismiss user error". But rather, than when your floor is zero, you're going to have a remarkably difficult challenge.

https://www.reddit.com/r/dredmorbius/comments/69wk8y/the_tyr...

If someone walks into a glass door once, you can say they weren't paying attention. If more and more people start walking into the same door, there's something wrong with the door.

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