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For those thinking about preventative solutions, there are some existing, all very expensive of course. The simplest is placing a row of red lights in the grou
by hn_user2 4y ago
For those thinking about preventative solutions, there are some existing, all very expensive of course.
The simplest is placing a row of red lights in the ground at all intersections to runways. When an airplane is cleared for takeoff and until it is airborne the controller presses a button and turns all these lights red. Pilots are instructed that regardless of clearance, a red light over-rides that, and to never cross it. These lights are installed at JFK, but apparently NOT at the intersection inquisition. (https://en.wikipedia.org/wiki/Runway_status_lights https://en.wikipedia.org/wiki/Runway_status_lights).
JFK also has Airport Surface Detection Equipment (ASDE). Which is essentially ground radar including transponder/ADS-B replies. Many have automated alerts when it detects a potential runway incursion. Not known if any such system alerted the controller.
There is obviously room for more to be done in this space.
- toomuchtodo 4y agoIf this doesn’t provide evidence for funding the install of RWSL at that intersection, I don’t know what does. What would’ve been the cost of loss of life and both airframes? Tens of millions at a minimum. Edit: thank you for correcting my damages estimate, I was off by at least an order of magnitude.
- sixQuarks 4y agoEach plane costs more than $150 million, plus at least 300 lives could have been lost. Damages probably close to a billion at least
- echelon 4y agoEach human life is worth approximately $10 million [1], so you're in the right ballpark. [1] https://en.wikipedia.org/wiki/Value_of_life https://en.wikipedia.org/wiki/Value_of_life
- IncRnd 4y ago$10 million is not what is stated at your link. "In Western countries and other liberal democracies, estimates for the value of a statistical life typically range from US$1 million—US$10 million; for example, the United States FEMA estimated the value of a statistical life at US$7.5 million in 2020." [1] That's also not the meaning of Value of Life, which is a statistical evaluation. On a commercial plane there are almost certainly multiple people whose individual Value of Life projections exceed $10 million. In many other cases, the value of life calculation for the very pilots of a commercial flight is less than $10 million. This all goes to show that this calculation is not for what "each human life is worth". This is a statistical evaluation for determining what would need to be paid to an individual to engage in a dangerous activity or to be paid to a survivor after a person dies from an activity. When someone decides to work at a 7-11 in a crime-ridden area for a greater pay compared to a 7-11 in a safe family area, they perform a type of Value of Life calculation. [1] From the first section of https://en.wikipedia.org/wiki/Value_of_life https://en.wikipedia.org/wiki/Value_of_life
- ddulaney 4y agoThe VSL used in this case is $11.8 million in 2021, the most recent year it’s been adjusted for [0]. $10m is the usual rule-of-thumb. When making policies, governments generally pick a single value. Those “micro” VSL choices are one way governments can arrive at that value [1], but it’s certainly not the only way — economists have developed a bunch of different models which have (in some cases) wildly divergent outcomes [2]. But the key takeaway is that, for government policy purposes in the US, all lives are treated as having the same value and that value is about $10 million. [0]: https://www.transportation.gov/office-policy/transportation-policy/revised-departmental-guidance-on-valuation-of-a-statistical-life-in-economic-analysis https://www.transportation.gov/office-policy/transportation-... [1]: How this VSL was calculated: https://www.faa.gov/regulations_policies/policy_guidance/benefit_cost/media/econ-value-section-2-tx-values.pdf https://www.faa.gov/regulations_policies/policy_guidance/ben... [2]: General VSL calculation methods: https://law.vanderbilt.edu/phd/faculty/w-kip-viscusi/368_Value_of_Statistical_Life_Oxford.pdf https://law.vanderbilt.edu/phd/faculty/w-kip-viscusi/368_Val...
- KRAKRISMOTT 4y agoWhy are the lights expensive?
- Dalewyn 4y agoManufacturing certifications, installation and maintenance inspections and certifications, auditing, etc. To put it into some relatable context, a simple electrical switch that you might grab for a few bucks at your local Home Depot would cost at least several hundreds of dollars because of all the red tape that must be satisfied for safety reasons. Safety isn't cheap.
- ars 4y agoThe extra cost for safety is reducing safety because it's causing this not to get installed. Maybe it's worth having a worse system that actually is there.
- jahewson 4y agoUnreliable systems aren’t there when you need them.
- deleted 4y ago[deleted]
- zmgsabst 4y agoNeither are nonexistent systems.
- Dalewyn 4y agoThere is a psychological element to it. If there's a safety mechanism that may or may not work, coming to rely on it is suicidal. If there is no safety mechanism in the first place, you (hopefully!) never become complacent in the first place. So it's better to either have a safety mechanism that will absolutely work every single time or nothing at all, than one that may or may not work and invite complacency.
- ajross 4y ago> For those thinking about preventative solutions, there are some existing, all very expensive of course. The simplest is placing a row of red lights in the ground at all intersections to runways. That's... a street light.[1] When street lights become "very expensive of course" it's time to revisit our priors about how we regulate. And I say this as someone not normally inclined to libertarian rhetoric. [1] To be clear: a proven and effective technology deployed successfully literally millions of times over the past century of traffic control!
- jamiek88 4y agoIt’s not a street light. You aren’t going to have poles or hanging lights on a runway. It is embedded lights. That have to work without fail in extreme temps, all weathers, with planes rolling over them all day. They have to have certain visibility at different angles, they have to fail gracefully. These things are rarely ‘that’s just…’
- ajross 4y agoRunway lighting is 80 year old technology; we solved all those problems long, long ago. I mean, come on. It's one thing to point out that problems are inherently complicated, but to pretend that we can't deploy something as obvious as, yes, a street light because of expense is making yourself part of the problem, not the solution.
- ClumsyPilot 4y ago> lighting is 80 year old technology The first gas turbine was invented in 1791 Are they cheap? Can you buy them for next day delivery?
- mopsi 4y ago> Are they cheap? Can you buy them for next day delivery? Yes. They are consumables comparable to bulbs and light fixtures at home, just good LEDs on a PCB in a metal/plastic case. It's sheer insanity to pretent that aerodrome lights are some magic technology.
- harshreality 4y agoBeyond detecting runway incursions, couldn't ASDE be integrated with some kind of RTS-like interface for ATC so they could indicate where planes should go next? Automated alerts could be broadcast to ATC and to the pilots if planes deviated from the plan, and the system could flag actions that risked costly but non-fatal ground collisions and other problems unrelated to takeoffs or landings.
- hn_user2 4y agoFurther, Electronic clearance delivery already sends instructions to the airplane electronically for their in-flight clearance. An electronic delivery of their ground clearance could be hooked up to navigation to highlight that route on the ground as well.
- crote 4y agoSome major airports already have Follow the Greens. Traditionally every taxiway and every possible path on each intersection will be painted with a yellow line and illuminated with yellow lights. Follow the Greens replaces that with green lights which are controllable at a very high resolution. The result is that every plane will have a path of green lights to follow, greatly reducing everyone's workload.
- giantg2 4y agoThese sound more like detecting something. How about preventing miscommunication? They weren't even on the correct runway.
- Retric 4y agoIt’s much harder to misunderstand a red light than verbal instructions.
- dotancohen 4y agoOne solution does not discount the other. In data security we talk about security in depth, security in layers, etc. The current proposal is _a_ solution, but not _the only_ solution nor even the only component of a comprehensive solution.
- giantg2 4y agoWhich is why I was asking about a solution that addressed the aspect of the issue that the first solution did not.
- boredhedgehog 4y agoWhere was the miscommunication? The pilot readback was correct.
- CaptainZapp 4y ago> Where was the miscommunication? The pilot readback was correct. "Runway 4L was being used for takeoffs. The American Airlines aircraft did not follow air traffic control instructions. ATC audio shows they were told to “”cross runway 31 Left at Kilo” and instead crossed runway 4 Left at Juliet, in front of the accelerating Delta Boeing 737." Crossing a runway, which you're not cleared to cross is a pretty bad case of miscommunication in my book.
- boredhedgehog 4y agoThat's the case when the readback is incorrect or missing, i.e. the pilot heard something that wasn't said. In this case, the instruction was communicated correctly on both ends. But it wasn't followed correctly.
- jupp0r 4y agoI'm not disputing that it's very expensive but I find it funny that the "install red lights" solution is considered to be vey expensive.
- kube-system 4y agoPeople die at intersections with stop signs every day, but we don’t do it on our roads for the exact same reason.
- benjaminwootton 4y agoMcKinsey style interview question. How many road intersections are there in the US?
- ackbar03 4y ago"our market analysis shows that price inelasticity and customer retention rate of opioids are insane! "
- ddalex 4y agoGoogle says that Quora user thinks: Can’t answer the second question, but as for the first one, there are 6,302,865 intersections for the 497 urbanized areas in the United States. ChatGPT says: I'm sorry, I don't have an exact number for the number of road intersections in the US. However, I can provide you with some information that may help you arrive at an estimate. According to the Federal Highway Administration, as of 2020, there were approximately 4 million miles of public roads in the US. If you assume that each mile of road has an average of four intersections (which would include cross streets, driveways, and other points where roads connect), that would result in an estimated 16 million road intersections in the US. However, this is just an estimate and the actual number may vary depending on factors such as population density, urbanization, and road infrastructure.
- rob74 4y agoI'm guessing three to four orders of magnitude more than there are intersections between runways and other runways or taxiways.
- jcgoette 4y agoWSJ article made it seem as if these lights were already in place: "Airport officials also inspected lights meant to indicate when it isn’t safe for planes to venture across runways and verified they were working at that particular runway, according to the summary."
- dev_tty01 4y agoSo, the American flight didn't follow directions or the lights. If that turns out to be the case, wow.
- heavenlyblue 4y agoI think what the parent want to say is that these lights do not exist. The sentence is written in a way that makes it seem they do (i.e. it's all theoretical in nature).
- sandos 4y agoCould also be that they were not correctly set, the pilots thinking "hey, no red lights, we can go! Its 100% safe".
- addandsubtract 4y agoWho are "they" in your sentence? I assume the lights and not the plane? Wouldn't lights like this be placed the same way on every airport implementing them?
- NoahKAndrews 4y agoI think they meant that the lights may not have been set to the correct state.
- KyleBerezin 4y agoThis is a good example of how ADDITIONAL safety systems can sometime become the de-facto safety system. A similar problem can happen with firearms, where if a mechanical safety is on, people sometimes disregard other rules of safe firearm handling, leading to accidents. Pilots have a lot of info coming in at any given time, and there has been a move to reduce the amount of info, so they can focus on the more important items. The answer isn't always more warning lights or alarms. Edit: By "This is a good example..." I am referring to the hypothetical situation, I am not confirming this actually happened.
- taspeotis 4y ago> but apparently NOT at the intersection inquisition https://www.google.com/search?q=%22in+question%22 https://www.google.com/search?q=%22in+question%22
- DonHopkins 4y agoNothing is working. Send in the nuns! https://www.youtube.com/watch?v=LnF1OtP2Svk https://www.youtube.com/watch?v=LnF1OtP2Svk
- innocenat 4y agoThis diagram suggest that it is installed at the intersection in question (J cross 4L) https://www.faa.gov/air_traffic/technology/rwsl/media/JFK.pdf https://www.faa.gov/air_traffic/technology/rwsl/media/JFK.pd...
- ralph84 4y agoYep. Both the intersection American 106 was supposed to take (cross 31L at K) and the intersection they took (cross 4L at J) have runway entrance lights. According to https://www.faa.gov/air_traffic/technology/rwsl/pet/ https://www.faa.gov/air_traffic/technology/rwsl/pet/ the lights don't illuminate until departing aircraft are at 30 knots, so it's possible Delta 1943 was just beginning the takeoff roll and the lights weren't on yet when American 106 decided to cross 4L.
- boredhedgehog 4y agoI believe that the causes for errors in perception and communication can be rather subtle, and therefore successful mitigations can be as well. If the root error of the pilot here happened not at the runway crossing, but earlier, when confusing the K and J taxiways, then that's the location where possible preventative solutions should be considered. Because once a pilot has subconsciously convinced herself that she's at another runway, it becomes increasingly impossible to override that mental block, no matter how many lights and sirens you use.
- rob74 4y agoIf you take a look at the airport diagram (https://www.faa.gov/air_traffic/publications/atpubs/aip_html/images/new_york1.jpg https://www.faa.gov/air_traffic/publications/atpubs/aip_html...), it just takes one wrong turn to end up on taxiway J instead of taxiway K. And, also from that diagram, once the American plane took the wrong turn, the controller had very little time to see that and stop it before it crossed the runway. But still, if pilots internalize via training that "if you are about to cross a line of red lights, you are entering an active runway without having permission to do so, so don't do it", that should be one more layer of safety to prevent situations like this. Of course, none of these layers are 100% foolproof, but taken together...
- bronco21016 4y agoRWSL take it a step further and are actually automatic based on ASDE. No controller input necessary. I'm not aware of the costs to install it but I really wish it was everywhere. It's an incredibly handy confirmation for clearances given by ATC.