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Comment by resolutebat | Hacker News Reader

It's rarely that straightforward: most all runway collisions involve ATC giving correct instructions, but the crew mishears them, misunderstands them, hears them correctly but accidentally goes to the wrong runway/taxiway, etc etc. And there's usually complicating factors like terrible weather, diversions to unfamiliar airports etc in the mix as well. What remains the world's worst single aviation disaster in Tenerife checked pretty much all these boxes.

https://en.wikipedia.org/wiki/Tenerife_airport_disaster

https://en.wikipedia.org/wiki/Category:Airliner_accidents_an...

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All of which would be prevented if the plane refused to steer onto a runway that it knows is occupied.

The ATC computer should talk to the plane computer.

Airplane taxiing is manual. ATC can tell the plane to use runway A, and the plane can check that A is free, but neither will stop the pilot from accidentally steering into runway B.

There’s nothing preventing airplanes from knowing the coordinates of every runway in the world and working out the truth using GPS though.

Modern passenger airplanes absolutely do have runway maps.

This would elevate the impact of GPS spoofing from a minor or major [1] nuisance to a significant terrorism threat.

[1] https://ops.group/blog/new-gps-spoofing-incident-shows-how-i...

Only if you rely on it for your positioning 100%. Presumably none of the existing measures would change.

Yeah, throw in different languages and accents and all kinds of variations and ... I tend to agree.

> The ATC computer should talk to the plane computer.

Not as simple:

1) You need to implement it for very small airplanes too, which is far from easy. In the Linate air disaster a small Cessna Citation invaded the runtime due to fog and misscomunication.

2) You need to implement it for ground vehicles too, as in the LATAM example it was a fire truck that invaded the runtime.

3) You need A LOT of infrastructural update.

4) Even if you had computers talking to computers, this may still be far from enough to avoid collisions, as those mistakes are often a matter of seconds (as in the both accidents quoted before).

5) Automation brings its own issues. One of them is complacency where attention levels unavoidably get lower as reliance on automation increases. In turn complacency can make runways more prone to such incidents in case of malfunctions/bugs.

You can have this as an additional safety layer.

You don’t need to update everything at once.

If anything is able to react within seconds, it’s a computer.

I think you might be way underestimating number 5.

While on the first hand your point sounds very reasonable, in practice it may have more adverse effects than we may think and make the whole system more unsafe.

I guess the question is if you think the current system is good enough.

The next big crash will change people’s minds on this.

No, the question is what authorities and regulators conclude, after this incident is properly investigated, regarding improvements and risk mitigation measures have to be put in place. Aerospace regulations are written in blood, and almost-blood, not in public outcry.

Regulators are people too

Last time I checked, in deed they are. For the most part.

It's hard to know what that is. TCAS is a great example of an obvious solution to mid-air collisions - two devices seamlessly negotiate for one plane to go up, the other to go down.

One I can think of is an electronic runway "lock". ATC mark the runway as locked to a particular aircraft. The landing aircraft checks at minimums whether if the runway is locked to any other aircraft. It's harder to know how to prevent incursions at ground level, but it could be a beacon near the runway threshold and intersecting taxiways, flashing a warning in the cockpit of the taxing aircraft if an aircraft on final holds the lock. A pilot could still disregard it. Sometimes two planes can share the same runway, such as a plane lining up while another vacates, which adds further problems.

I'm not aware of any system like this.

Runway Status Lights (RWSL) are close to what you're describing. If surface surveillance radar detects that a runway is occupied, it turns on red warning lights at the runway approach end and at the hold-short bars.

The nice thing is that the entire system is ground-based, no additional equipment needed in the aircraft.

However, it's complicated/expensive, so only a handful of airports have it installed.

https://en.wikipedia.org/wiki/Runway_status_lights

You're right. Regrettably, I just read that Haneda is one of the handful that have it, but the system was broken.

A great example of how an aircraft accident is almost always a result of multiple things going wrong.

https://abcnews.go.com/International/japan-airlines-flight-c...

This is a gross oversimplification.

Yes, in this case, you do need to update everything at once. At least for a given aiport. All it takes is one plane, helicopter, fire truck, or baggage transport vehicle to screw with the assumptions of the system and jeopardize safety.

No, computers aren't necessarily faster, assuming we want to achieve autonomy on the ground. Note that the average human reaction time to visual stimulus is about 250ms. Achieving this on a plane would require a great deal of cameras and sensors that would not only need to stay clean, but capable of withstanding pressure changes, high velocity winds, the occasional unfortunate airborne debris, etc. Then there is the processing power to both process each input in real-time (per plane) and train it on real-world data to recognize a variety of scenarios to act upon (per model and perhaps configuration; AA alone has about 11 active aircraft types across 953 planes). Contrast this with Tesla's investment for approximately 6 models. [1]

Achievable? Sure. Cost-effective and sustainable with current tech? Doubtful.

[1] https://www.theregister.com/2023/07/21/tesla_dojo_spending/#....

>1) You need to implement it for very small airplanes too, which is far from easy.

No, you don't. It's easy: just don't allow small airplanes at airports with large commercial aircraft. No one needs them anyway; they're just a luxury for rich people. The only place they make sense is for very remote locations, like Alaska, where there's a need for people to pay for carriage on such a small aircraft. For normal airports that carry jumbo jets, there's no reason to have small planes sharing the runways. For exceptions like coast guard jets such as this one, these are government-owned so they can afford the upgrades.

The absolute worst thing is for an aircraft to refuse control input from the pilots, regardless their state of informedness. Lest we forget, we saw what happens when computers take priority over pilots thanks to 737 MAX MCAS.

Okay, so let’s add an override.

That system had an override didn’t it, just wasn’t well known?

Then let’s make it obvious and include it in the training.

>Then let’s make it obvious and include it in the training.

Which cuts right to the heart of the B737 MAX issue - Boeing substantially changed the design, then added sensors & software to make the changed airframe handle similarly to the old 737 airframe and claimed that this meant the pilots did not need retraining

If Boeing had been upfront about MCAS, and required that pilots were trained in what it did and how to override it then the crashes probably would not have happened.

Training or not, the system was not obvious and the override was even further from obvious.

No, we need more than this: the system must be documented and pilots must be trained for it. If the aircraft manufacturer fails to do this, they go to prison. If it's found that hiding this information was intentional, the corporate executives and everyone else in the company who knew are publicly executed by firing squad (with them aiming at their stomachs).

This exists.

- https://skybrary.aero/articles/runway-awareness-and-advisory...

- https://skybrary.aero/articles/autonomous-runway-incursion-w...

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