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Comment by willidiots | Hacker News Reader

Seems like a design flaw. Do any taxiways have markings etc. to make them more distinguishable?

They do. They have different lighting systems/colours etc. to differentiate them.

Taxiways generally have green lights along the centerline to guide aircraft rolling on the ground, but runways usually have white (bright) lights along the edges. There are times when even THAT causes confusion, because sometimes the taxiway centreline lights can look like the edge lights of the runway - especially if the light is refracting off a wet windscreen.

So, in the end the problem is generally avoidable, but if you are on finals at a really busy airport after a gruelling 20 hours trans oceanic flight, at night, in the rain, and the tower is trying to hurry you up to expedite traffic, you can make mistakes.

Perhaps this is a dumb question but is there any reason why the taxiway doesn't have HUGE red Xs going down it and the runway with HUGE green arrow going down? Sorta like what they do on bridges where the lanes can shift to allow more cares to travel in one direction but more obvious? They could even angle them so the planes on the ground see them differently or not at all.

Red 'X's on a runway usually denote an inactive or out of service runway.

They ARE actually quite different in terms of lighting, width etc. and 99.9% of the time there is no issue telling them apart. Runways also have extra approach lights etc. at night to really make it clear where you should be pointing the nose.

(NB: Check out the video posted elsewhere in this thread of the cockpit view of a 747 landing at SFO at night. It is pretty clear which is the runway and which is the taxiway).

However, it is those 0.01% of the times where the weather is bad, or you are landing into the sun or the traffic is really congested and you are trying to talk on the radio at the same time etc. where mistakes can be made.

In this particular scenario in the OP, I am assuming that having 4 heavy aircraft lined up on the runway pointing at the landing plane, then 4 sets of bright landing and navigation lights on the taxiway could have looked like runway lighting, and disoriented the Canada Air pilot? Just outside speculation here, but stranger things have happened.

It's like the case of the Air New Zealand CD-10 crash into Mt. Erebus in clear weather. Non pilots were incredulous that a plane could fly into the side of a mountain in clear daylight weather, but the visual trickery played by bright snow on a slope actually fooled ALL pilots on board that they were flying down a valley instead of into an upward slope. [0] (A badly programmed navigation computer didn't help at all.)

[0] - https://en.wikipedia.org/wiki/Air_New_Zealand_Flight_901

The a/c on the taxiway will not have their landing lights on while pointed downwind.

They turn them on when theyre cleared to enter the runway.

Just a very naive question, would not it be possible for the taxiway lights to only be visible from the ground?

A good concept in theory, but bear in mind that the cockpit of a 747 or A380 is something like 2 or 3 stories above the ground, in terms of height.

To be able to see a taxiway light 50m in front of the plane, the light will have to be angled up to an extent that a plane 500 feet in the air a mile away will also be able to see it.

Not putting down your idea at all - anything workable that will improve flight operations should be considered.

Trivia: Speaking of lighting assistance, Did you know one of the best inventions out of Australia is the T-VASIS landing system [0] that is in use at nearly every major airport in the world?? Oh, and we invented the DME too [1], in the aviation world... :)

[0] - https://www.dst.defence.gov.au/innovation/tee-visual-approac...

[1] - https://en.wikipedia.org/wiki/Distance_measuring_equipment

A good concept in theory, but bear in mind that the cockpit of a 747 or A380 is something like 2 or 3 stories above the ground, in terms of height.

Fun fact! The A380's flight deck isn't that high off the ground. It's exactly the same height as the A330 and A340, part of an effort to reduce differences and cut down on the amount of new things pilots would have to deal with to train on the type.

This is also why the A380 has such a pronounced "forehead" -- the much lower flight-deck height (compared to a 747) means there's a lot of plane above that.

(and bonus fun fact: the 747's flight deck is way up top not for visibility, but because Boeing anticipated supersonic planes would take over the passenger market; the 747's high flight deck was meant to accommodate converting the plane to cargo use, so that the whole nose could swing open for loading and unloading)

Australia is also responsible for "black box" flight recorders, which are one of those things where it's really hard to appreciate in hindsight why we didn't mandate them much sooner.

Seems like a very good argument for autopilot landings.

And yet, when the Asiana accident happened the complaint was that the pilots were relying on automation too much and didn't know how to properly hand-fly the airplane anymore.

Not all runways are equipped for ILS landings. Sometimes the ILS equipment gets taken out of service for maintenance. And even autoland has its limitations.