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Comment by jefftk | Hacker News Reader

Over 50%, sure, but 50% of a very small number. How many deaths do you expect keeping passengers from being distracted at these times would prevent?

(I expect if you compare that to the number of people inconvenienced by the rule it's a terrible trade off.)

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The number of fatalities and injuries seems minuscule because it's normalised over distance traveled.

This makes sense, because air travel is the only way to make voyages over this distance. But it also doesn't make sense for the same reason -- it's stupid to compare a 6000 mile holiday flight with a 6000 mile holiday road trip, because people don't routinely make those. You're still more likely to get injured on an eight hour car ride than on an eight hour flight, but the difference isn't a factor 600.

In much the same way, air travel is also arguably moderately efficient in terms of CO2 per mile, except that it's also a super easy way -- in fact, practically the only way -- to accrue tens of thousands of miles every year, so the efficiency is kind of irrelevant.

I know people who are already at the "if driving takes less than 8 hours, I'd rather drive than fly" level. Every additional inconvenience (or psychological impediment) added to the safest mode of long-distance travel has a risk of decreasing overall safety.

It's not particularly relevant to an international flight into Japan, but the extent to which increasing annoyance/instilling fear of airline passengers causing people to drive instead must be weighed against the small safety benefit resulting from a policy of telling passengers "we think this phase of flight contains the most highly concentrated risk, so for the next 15 minutes, please put away all of your distractions, prepare for a possible crash, and try not to think about the fact that we could turn this aircraft into a tumbling, burning ball of wreckage at any moment."

Something similar was the primary justification to support the continuation of "infant in arms" travel by passengers under the age of 2, with an expected 60:1 ratio of lives that would be lost if infants were required to occupy ticketed seats vs being carried in arms.

https://www.ntsb.gov/news/events/Documents/child_safety-Clau...

For other people who might not have followed completely: the NTAB don’t say (explicitly) that forcing children to occupy a seat of their own would result in 60 times as many deaths. They estimated the risk of lap infant deaths as 1 every 10 years, and then they estimated that if the cost of travel increased for families, enough families would instead choose to drive that 60 infants would die in road accidents in that same 10 year period.

Thanks for posting that. It was perfectly clear in my head, but I really made a hash of describing it when summarizing it my post upthread.

I once traveled for business from Salt Lake City to Fort Collins, Colorado.

1/2 hour to the airport + get to the airport 2 hours before flight + 1 hour direct flight to Denver + 1/2 hour to deplane + 1/2 hour to get bags + 1/2 hour to get rental car + 1 hour drive to Fort Collins. Total 6 hours. Seems like it actually totalled 7 but I don't remember where the extra time was.

Versus 7 hours drive time from Salt Lake to Fort Collins.

And if two people are going, you only drive one car, but you buy two plane tickets.

And my car has more legroom than a coach seat.

So, yes, flying is safer per mile, but the "under 8 hours" crowd also have a point...

I pretty much have gotten to where I only fly if driving is impossible (e.g. crossing an ocean).

That’s me. But for totally different reasons. I’m a 4-5 hour round trip by car to the nearest airport that actually flys anywhere. So unless it’s more than about a 8-10 hour drive, it’s faster (and way cheaper) to drive than fly.

Unfortunately, there's very little detail on how they arrive at the 60:1 ratio in that PowerPoint presentation.

We literally decided to drive from UK to Poland this year(12 hour overnight ferry + another 12 hours of driving) instead of flying, because we hate Christmas flying so much, it's always a shit show, we always end up ill because everyone is coughing, at least with driving we can take it at our own pace - we want to stop, we stop.

The statistics are also available as "per passenger-hour", which eliminates the speed factor. An 8 hour road trip is reasonable. An 8 hour flight is on the longer side.

An 8 hour flight is a normal intercontinental flight, not even particularly long (London - New York/Delhi/Nairobi/Dubai sort of distance). Longer flights like London-LA/Singapore/Joburg/Tokyo are perfectly normal, or reasonable.

I would rarely do 8 hours driving in a single day, let alone 12. Certainly couldn't do that for work, would be massively against policy.

Similar to the Jevons Paradox, where increases in energy efficiency often lead to greater overall consumption, as the higher efficiency broadens the scope of the activity.

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

And for anyone who remembers the electronics during takeoff and landing ban once cell phones became common it was a massive hassle for flight attendants as many passengers routinely ignored instructions.

Never really understood this "we can't enforce the rules because people routinely ignore the rules" attitude. This should be dead simple on an airplane, where the airline knows who each passenger is by seat. So have one flight attendant make one pass down the aisle warning everyone to put away their phones, then have another one follow a minute or so later just making note of which seats are still using their phones. No-fly-list them all later. After this policy became known, people would be strongly incentivized to get with the program.

Even when there was a rule that cell-phones were supposed to be turned off, studies showed that 20-25% of cell phones were still active (Possibly forgotten in pockets) - wasting time, energy, traveler patience, on something that was entirely theater (I don't believe there was ever a single incident associated with an active cell phone - which makes sense given the 10s of thousands per day that were powered on during takeoff) - seems like the worst possible tradeoff ever. The "No cell phone use during takeoff" or "No mobile phone use during flight" (China Air used to do that - very, very annoying) - bureaucracy flex just because the could.

I think the "no cellphones" rule is about minimizing distractions during critical phases of flight, not because a phone's radio is going to do damage to the aircraft. So a phone on but sitting in someone's bag is not the end of the world.

> the "no cellphones" rule is about minimizing distractions during critical phases of flight, not because a phone's radio is going to do damage to the aircraft

The cell-phone "ban was put in place because of potential interference to wireless networks on the ground" [1]. The distraction argument started making its rounds after the interference hypothesis was debunked.

[1] https://web.archive.org/web/20120110081053/http://www.fcc.go...

Aircraft electronics were also a commonly given reason for a time. And as for distracted ions there was a period when you could read a physical book but not a Kindle.

> I think the "no cellphones" rule is about minimizing distractions during critical phases of flight

Along with the "no newspapers" rule? And no sleeping?

No distraction? Do you need sub 500ms response time? I'm pretty sure that even someone watching a movie with noise canceling earphones was aware of an issue just because of physics…

> No-fly-list them all later

Then the airline lays off those people because nobody wants to fly.

> How many deaths do you expect keeping passengers from being distracted at these times would prevent?

As of today: 379.

Passengers were using their phones during landing (including at least one that posted footage from inside the plane on social media), so...no?

Incredibly, people can walk and chew gum at the same time. This includes the ability to refocus their attention when they experience unusual events.

>Incredibly, people can walk and chew gum at the same time. This includes the ability to refocus their attention when they experience unusual events.

No. They can't. That 'refocus' you mention is proof of that.

it's getting old having to say over and over again that this isn't actually the case : humans switch contexts and lose focus -- you're not as good at multi-tasking as you think, nor is anyone.

So , people can walk OR chew bubble gum , and if these choose to they can pay contextual switching costs between the two to make outside spectators believe that they can do two things at once.

Don't fall for the ruse, there is a cost even if it's a small one.

Similarly, in a disaster i'd rather be surrounded by fit young soldiers without cell-phones -- alert and aware -- than I would be surrounded by the typical multi-variant airliner crowd that must have their attention drug away from the device by the sound of crunching metal.

It's obvious to me that a group of alert and ready people will outperform 'the other group' in an escape in nearly every metric, i'd hope that the same would be obvious to the other humans trying to escape fiery wreckage alongside me.

[0]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7075496/ [1]: https://en.wikipedia.org/wiki/Human_multitasking

You are not rebutting what people were actually talking about in this conversation.

You're allowed to use phones during landing; they don't present much of a challenge for evacuation.

You're not allowed to use laptops or have the tray down.

You're not allowed to use laptops or have the tray down because those are active physical hazards even in fairly routine landings not because of some nebulous idea of you being "distracted".

This thread was started with throw0101d saying "I think forcing people to not have any distractions during take-offs and landings is a good thing", and we've been discussing how to weigh the inconvenience and boredom of prohibiting distractions against the reduced risk of death via more efficient evacuations.

The idea of putting down your phone for an hour in total being "too inconvenient" as people seemingly willingly sign over their dignity for a $10 cheaper flight ticket is.... uninspiring.

It sounds like people vary a lot in their preferences?

For example, I wouldn't take a $10 cheaper flight which prohibited using my phone, but I probably would take one that gave me a 1" narrower seat.

You seem really certain that passengers would be so wrapped up in their phones that they would be too distracted to promptly realize... there was a collision with another plane, causing their plane to split open and burst into flames.

OK.

That 'prompt realization' takes actual time from an escape when it doesn't necessarily need to.

I have no problem with the idea that humans can re-prioritize; but I do have a problem that people seem to think that the re-prioritization effort comes for free, instantly. We don't work that way as humans.

There's phone footage from inside the burning plane, so apparently your theories don't correspond with reality. Always quite annoying when that happens. Been the death of many a theory.

    people seem to think that the re-prioritization effort 
    comes for free, instantly

Here are the two biggest flaws in your thinking:

1. You seem to be assuming the alternative to "using one's phone during a landing" is some sort of highly aware ready state. In reality it's probably bored snoozing or half-snoozing. It's a red-eye flight after all.

2. You seem to be assuming that "evacuating a burning plane" is some kind of split-second thing, like a quicktime event in a video game. In reality, at least for this incident, there was a span of a significant number of seconds between "impact" and "plane slows down enough for emergency slides to extend and evacuation to begin." 30, maybe 60 seconds.... I'm not sure, but there was no real positive action for a passenger to take during that time. Shifting attention away from one's phone certainly has a nonzero time cost, but not remotely comparable to the time it took for the plane to come to a full stop.

Again, you're dealing in hypotheticals, while the actual reality of this incident (phones in use, orderly exit achieved, all lives saved) contradicts whatever it is you are imagining.

Where's that number coming from?

The number of souls on board for JL516.

* https://en.wikipedia.org/wiki/Japan_Airlines_Flight_516

But all JL516 passengers survived? How would keeping these passengers from using their phones during landing have reduced their deaths?

AF358 was engulfed in flames with-in three minutes (180s):

* https://www.youtube.com/watch?v=O5jSyaj_JwE

* https://en.wikipedia.org/wiki/Air_France_Flight_358

The FAA mandates that aircraft are able to be evacuated with-in 90s:

* https://www.faa.gov/documentLibrary/media/Advisory_Circular/...

Even for something as big as an A380 in its 800+ passenger configuration:

* https://www.flightglobal.com/airbus-a380-evacuation-trial-fu...

* https://simpleflying.com/aircraft-90-second-evacuation/

The difference between 180s and 90s is 90s: if (e.g.) ~30 people out of ~350 passengers (<10%) take an extra 3 seconds each because they are not aware of their surroundings, that time is eaten up.

Seconds matter.

I think maybe you're under the impression that:

1. Passengers on JL516 were not permitted to use their phones during landing.

2. I'm proposing that we start allowing them to use their phones.

3. If we did that then all 379 passengers would have died [1] because evacuation would have taken longer than the time before the plane was engulfed in flames [2]

Except #1 isn't the case: passengers were allowed to be on their phones and were doing so. And so #2 isn't the case either: I'm proposing maintaining the status quo.

And even if we had granted #1 and #2 I don't see how you get #3 because even if the extra time were entirely eaten up by 30 distracted passengers this wouldn't get you 100% dead: people don't leave in a single batch determined by the speed of the slowest person. There are multiple parallel exits, and each exit operates serially.

[1] https://news.ycombinator.com/item?id=38841170

[2] https://news.ycombinator.com/item?id=38842440

> And even if we had granted #1 and #2 I don't see how you get #3 because even if the extra time were entirely eaten up by 30 distracted passengers this wouldn't get you 100% dead:

You are right that it does not necessarily follow that 100% would be dead. AC 797 had a flash fire after 90 seconds, and only about half the people died. ¯\_(ツ)_/¯

* https://en.wikipedia.org/wiki/Air_Canada_Flight_797

People keep pointing out to you that passengers were in fact using their phones to record footage of the interior of the plane (eg to let their friends/relatives know what was going on in case they didn't make it). Of course people are easily distracted by phones when they should be paying attention to other things, but virtually all people already in an emergency situation are fully present unless they're injured or caring for an injured person. I think you're underestimating people's ability to multitask when they know it matters.

I once heard a wise doctor say that even if the chance of survival for a medical operation is either 10% or 90%, the practical chance the patient is battling is always 50% because he either lives or dies from that operation.

Likewise, the chance of someone being in an aviation accident is close to nil (you're more likely to be in a car accident), but you are either going to be in an aviation accident or not (a 50% chance) and you're going to be either dead or alive from it (a 50% chance).

So you might as well at least not have your epitaph be "Killed by some bozo in the aisle TikToking" if you do end up dying.

> even if the chance of survival for a medical operation is either 10% or 90%, the practical chance the patient is battling is always 50% because he either lives or dies from that operation

I think this is rarely a productive way to think about it. For example, the chance that I might die in the next year is somewhere between 0% and 100%, and actuarial tables put it somewhere around 0.3%. [1] Should I refrain from having a kid because I'd have a "50% chance" of leaving them without a dad before they turned 1?

[1] https://www.ssa.gov/oact/STATS/table4c6.html

Well, using this logic, every day you have a 50% chance of dying, since you either die or you don't. Or perhaps every second you have a 50% chance of dying.

...obviously this "math" doesn't quite work out.

I mean, it clearly doesn't work if taken to be literal probabilities. But I think it also doesn't work as a more metaphorical guide to life?

It clearly does not work in any circumstances. We over-emphasise the likelihood of rare events already, saying that something has even odds just because it is conceivable that it could happen is completely useless.

Which is not to say that you should not plan for extremely rare events, but you certainly should not make decisions assuming they are likely to happen.

There's also a 50/50 chance a world ending meteor hits in the next minute. But don't worry, there's a 50/50 chance you'll win the lottery tonight.

I think you're maybe missing the point. My understanding would be something like:

My chances of being killed by a shark is basically 0%. But, if I'm in a shark cage surrounded by sharks the idea that some global probability is 0% isn't relevant. Something like that?

If I'm in a shark cage then the probability that matters is conditional on being in a shark cage, sure. And it should certainly be higher than the global probability. But I don't see how this connects to saying that anything that can go two ways is 50-50? ("always 50% because he either lives or dies from that operation")

I think the 50% part should be ignored and the message is "when dealing with an individual sample, the general probability distribution isn't that useful?" I don't actually agree with that, just trying to steel man the point a bit. I do kind of see what he means

There's a 50% chance that this doctor failed probability

Cue 50-50 scene from the movie The Naked Gun:

* https://www.youtube.com/watch?v=aLLbuyWBCzQ

Also relevant (hilarious movie btw): https://www.youtube.com/watch?v=DrezGdru6TQ&t=20s

And an analysis of the scene: https://puzzlewocky.com/fallacies/the-50-50-fallacy/

I had a dentist explain to me that my lip could go numb with a 50% chance after my wisdom teeth removal with that exact explanation just two minutes before the surgery. I was infuriated, turns out I was on the lucky side of her coin.

I could be wrong, but I really don’t think permanent loss of sensitivity is anywhere that high. Though it sounds low for temporary loss, but then it goes away after a couple of hours or so.

It can really depend on how badly impacted the wisdom teeth are. There's apparently a lot of nerve bundles around the back of the jaw bone. If they really need to dig in there to get it out there's a risk. I've had multiple dentists talk to me about my wisdom teeth and all have talked about there being some significant risks with mine.

Yep, that was for permanent loss.

I recall the original context was that telling a patient to not worry because the chance of success is high isn't actually helpful, because the objective argument doesn't take into account the patient's personal perspective.

I've since extrapolated that to meaning that objective measures cannot always tell or respect the whole story, because personal perspectives can bowdlerize everything down to life or death or a 50% chance.

To put it another way: Telling someone they have a negligible chance of being in an aviation accident is worthless comfort if they end up in one.

> Telling someone they have a negligible chance of being in an aviation accident is worthless comfort if they end up in one.

It's significant comfort in all those flights where no crashes occur, and for most of the time up to and during those that do end in crashes.

Anyone who really believes they are about to embark on an activity having a 0.5 probability of killing them should put their affairs in order, but then, by the same reasoning, there's a 0.5 probability of dying while doing that!

I believe the fallacy here is using an uninformative uniform prior when a much better, empirically-verified one is available.

>because the objective argument doesn't take into account the patient's personal perspective.

Suppose a friend is afraid of crossing the street. Would it be more helpful from a personal perspective POV to tell your friend the odds of being hit by a car, or to make up the fact that you are just as likely to die today crossing that street as not dying? Because the latter strikes me as unhelpful from either an objective perspective or a personal perspective.

> To put it another way: Telling someone they have a negligible chance of being in an aviation accident is worthless comfort if they end up in one.

Sure. It’s also callous and insensitive, which is why we don’t tend to do that. But saying to the vast majority who are never going to experience a plane crash (a number larger than the number of victims by a few orders of magnitude) that it’s a coin toss is at least not very smart.

The purpose of probability is not to give you good feelings

(I don't think that's what most mean when they say 'chance', but I get what you mean ;) It's similar to realizing how seating choice radically alters your (very small) chance of death by train crash.

I was going to say 'chance of death on that day' but apparently rail transport is remarkably safe and in micromorts, you're as likely to die in one day at 20 years of age as in 10000 km by rail, or (only!) 1600 km by air.

Now, it appears that 1600 km is also nearly the distance of the average passenger flight (a disappointly difficult datum to discover on the internet in 2024). Is this a counterpart to the reassuring quips comparing the chances of death by lightning: that boarding a plane doubles your chances of dying that day?

https://en.wikipedia.org/wiki/Micromort#Travel

This is very silly. There are much better ways to express the idea that a binomial distribution is different than a multinomial or continuous one than to make up fake statistics.

By that logic, there's a 50/50 chance the sun will come up tomorrow.

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