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Comment by throw0101c | Hacker News Reader

> There's 1700+ runway incursions a year in the US alone, each one should be investigated as if an accident occurred and fixes proposed. Like when an accident occurs.

How many runways crossings are there in a year? How much is "1700+" a percentage of that total?

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A "runway incursion" is a very broad term that includes everything from this accident to a single engine Cessna moving past the hold short line prematurely at a quiet airport.

FAA defines it as "Any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle or person on the protected area of a surface designated for the landing and take off of aircraft." [0]

Many runway incursions run no risk of any accident, but are still flagged as issues, investigated, and punished if appropriate.

[0] https://www.faa.gov/airports/runway_safety/resources/runway_...

The point is that it doesn't matter what percentage of the total they are, it's that 1 is too high without adequate explanation (the Gimli Glider caused vehicles to be guilty of a runway incursion by turning an abandoned runway into an active one, for example).

And the cost of investigating 1,700 should be within the budget.

Of course it matters. All of these entities have limited budgets and personnel and almost unlimited ways they could apply those resources. They have to choose what to chase and they do that by deciding how big of a problem it is.

You can't know how big of a problem it is without an investigation. Frequently, the initial "obvious" cause of a collision or incursion turns out to be a multi-layered set of failures. Tightening up procedures or recognizing a previously overlooked defect in the systems makes us all safer and should be prioritized.

We talk about Vision Zero for streets. Vision Zero is actually achievable in aviation.

If 1,700 is a huge percentage of runway uses (obviously it isn't but grant it, say at a single airport), then it's mandatory it be investigated because it's so huge.

If 1,700 is a minuscule fraction of all runway uses (as it likely is) then investigating it should be a proportionally minuscule amount of the budget.

There are five categories of incursion, with the top one being where a collision occurs:

* https://en.wikipedia.org/wiki/Runway_incursion#Definition

* https://www.faa.gov/airports/runway_safety/resources/runway_...

All incursions (in the US) are tracked:

* https://www.faa.gov/airports/runway_safety/statistics

Given there are ~45,000 flights per days in the US (and so aircraft and vehicles would move hither and fro around an airport for each flight), 1700 feels like a small number.

Exactly - it's a small number and should be investigated, because if we reduce the number of all incursions, we reduce the number of collisions (and fatalities).

They are classified as operation/ATC error, pilot error, and vehicle/pedestrian error.

Human can misspeak or mishear instructions, but if they were communicated and understood correctly (a read back was correct), but the pilot had a 'brain fart' and went forward instead of stopping, how do we eliminate brain farts?

That's a big part of the story of aviation; the way things are communicated has changed because of brain farts, the way things are lined up, etc.

See 5-2-5 for an example:

https://www.faa.gov/air_traffic/publications/atpubs/aim_html...

NOTE- Previous reviews of air traffic events, involving LUAW instructions, revealed that a significant number of pilots read back LUAW instructions correctly and departed without a takeoff clearance. LUAW instructions are not to be confused with a departure clearance; the outcome could be catastrophic, especially during intersecting runway operations.

The older term was "hold short runway X" and that was too close to "hold runway X" - the first meant do NOT enter the runway, the second meant enter and line up but do NOT takeoff.

The old version of “line up and wait” was “taxi into position and hold”. “Hold short of runway” is still in use but means something different.

My very fuzzy back of the envelope says easily 10s of thousands per day.

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