Fliers Must Turn Off Devices, but It’s Not Clear Why • Hacker News Board

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#221

Post by bambax » Mon, Nov 28, 2011, 10:20 AM UTC

Bud wrote: post #8

There is actually a very logical, sensible reason to have everyone power off and stow their devices during takeoff and landing, and this story disappointingly failed to cover it: By far the most likely time for any accidents or incidents to occur is during takeoffs and landings. If everyone has 15 objects out and is busily typing away, it's going to be tht much more difficult for flight attendants to get everyone's a…

Why is reading authorized, then? Or, worse, sleeping / wearing earbuds? Or doing anything except getting ready for the coming catastrophe?

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#222

Post by gnaffle » Mon, Nov 28, 2011, 10:22 AM UTC

tomkarlo wrote: post #136

lucasjung wrote: post #37

Earlier quoted context omitted.

I currently work in developmental flight test. Any time we add a new piece of electronics to an aircraft (or replace an existing piece with a new version), be it a radio, a computer, or test instrumentation, we have to conduct an Electromagnetic Compatibility (EMC) Safety of Flight Test (SOFT) to make sure that the new equipment does not interfere in any way with avionics that are critical to safety of flight. Even i…

From a safety standpoint, isn't the right thing to do to test flight equipment against interference from consumer devices? Simply assuming that everyone on the plane will turn off their cell phone seems like a cop-out. Having flight safety depend on the (unverified) compliance of consumers is ridiculous. There are only two cases here: 1. Consumer electronics represent a real threat to air safety. They should be banne…

3. Consumer electronics are not a big threat to air safety, but they can (and have, see Wikipedia article / NASA study) interfered with airplane navigation instruments.

Since it's much more likely that 1 out of 100 or 300 active devices will cause interference during takeoffs and landings than 1 out of 4-5 that are turned on by accident or ignorance, it's better to err on the side of safety and tell everyone to turn them off.

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#223

Post by monkeypizza » Mon, Nov 28, 2011, 10:41 AM UTC

city41 wrote: post #171

ramanujan wrote: post #71

Earlier quoted context omitted.

The FAA/TSA alway justify things in terms of "safety" and "security", but never calculate the massive costs associated with seizing billions in toiletries and productivity. Let's calculate that. There are about 800 million[0] passengers on domestic and foreign owned airlines in the US market, with many people flying more than once per year. Each person is taxed between 1-2 hours in terms of "safety" regulations, rang…

I don't understand how planes are seizing productivity when the nearest competitor -- an illegally driven car -- is about 5 times slower. Yes they have quite a bit of overhead during take off, landing, baggage claim, driving to the airport, security screening, etc. But what else can reduce a trip's time from days to hours? The amount of time wasted in that overhead compared to the time gained is minuscule.

The competitor is planes without the TSA, not cars.

By your reasoning, it would be wrong to complain about cars which have a speed limit of 40 miles an hour, since "the nearest competitor" (bikes, horses?) would still be still worse.

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#224

Post by zeteo » Mon, Nov 28, 2011, 10:41 AM UTC

cperciva wrote: post #202

zeteo wrote: post #163

If airplanes were vulnerable to radio frequencies, then terrorists have no need to acquire SAMs. A nice powerful amateur radio should do much better.

Avionics systems are better shielded against external interference than they are against internal interference.

Based on how Faraday cages work, I don't see how that's possible. Do you have a technical explanation or did you just pull that out of thin air?

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#225

Post by gnaffle » Mon, Nov 28, 2011, 11:08 AM UTC

ramanujan wrote: post #71

Bud wrote: post #8

There is actually a very logical, sensible reason to have everyone power off and stow their devices during takeoff and landing, and this story disappointingly failed to cover it: By far the most likely time for any accidents or incidents to occur is during takeoffs and landings. If everyone has 15 objects out and is busily typing away, it's going to be tht much more difficult for flight attendants to get everyone's a…

The FAA/TSA alway justify things in terms of "safety" and "security", but never calculate the massive costs associated with seizing billions in toiletries and productivity. Let's calculate that. There are about 800 million[0] passengers on domestic and foreign owned airlines in the US market, with many people flying more than once per year. Each person is taxed between 1-2 hours in terms of "safety" regulations, rang…

How many airports make you spend an hour or two going through security? When flying, I usually spend an hour or two in total at the airport, but that includes check-in, security, waiting for and boarding plane, then de-planing and sometimes waiting for luggage. Not to mention the transport time to and from the airports. Security and safety is a pretty insignificant part of that time, and waiting in line at the airport the price you pay for getting cheap airfares.

You can buy yourself out of this miserable experience by renting a plane. Of course, you might still get a security briefing by the pilot, as part of a checklist that he's already gone through hundreds of times while wasting precious time.

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#226

Post by cperciva » Mon, Nov 28, 2011, 11:08 AM UTC

zeteo wrote: post #224

cperciva wrote: post #202

Earlier quoted context omitted.

Avionics systems are better shielded against external interference than they are against internal interference.

Based on how Faraday cages work, I don't see how that's possible. Do you have a technical explanation or did you just pull that out of thin air?

Planes (well, most of them at least) have metal skins. The avionics -- and the passengers -- are inside this skin.

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#227

Post by mike-cardwell » Mon, Nov 28, 2011, 11:11 AM UTC

T-Winsnes wrote: post #172

ramanujan wrote: post #71

Earlier quoted context omitted.

The FAA/TSA alway justify things in terms of "safety" and "security", but never calculate the massive costs associated with seizing billions in toiletries and productivity. Let's calculate that. There are about 800 million[0] passengers on domestic and foreign owned airlines in the US market, with many people flying more than once per year. Each person is taxed between 1-2 hours in terms of "safety" regulations, rang…

Lets say we use an average of 15 minutes for a person to go to the toilet. This includes getting to and from the toilet etc. For ease of calculation we say that each person goes to the toilet twice during a workday. And there are roughly 7 billion people on the planet. That gives us 0.5 hour per person per day * 7 billion people = 3.5 billion wasted hours. At a conservative estimate of $10 per hours, that's $35 billi…

15 minutes to go to the toilet? I think you need to see a doctor.

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#228

Post by lucasjung » Mon, Nov 28, 2011, 11:20 AM UTC

ghshephard wrote: post #127

lucasjung wrote: post #79

Earlier quoted context omitted.

They would have to test every model of iphone against not only every model of commercial airliner in operation in the U.S. (including puddle-jumpers), but against every major variation in avionics suite among each model. This testing is not cheap. Even for Apple, it would be prohibitively expensive.

There's probably only 80 different commercial airplane models. This testing probably costs around $1000/hr - figure 5 days testing @ 8 hours a day = 3200 hours = 3.2 million dollars. Seems to be a reasonable price to pay.

As I said, it's not just the different models, it's the different avionics suites within each model (e.g. two aircraft of the same model might have different radios or different navigation equipment, etc.). For each plane, you would need a few hours of testing, which probably costs more than $1000/hour: you have to pay for the plane, the crew (who have to be qualified to perform this type of testing), the ground support equipment, maintenance support, and any fuel burned during testing (e.g. running the APU to provide power during testing will consume a small but not insignificant quantity of fuel).

EDIT: Almost forgot: After the testing is complete, you have to pay to have a test report written up and published, and then you have to pay for the FAA certification process. Probably not cheap.

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#229

Post by ibisum » Mon, Nov 28, 2011, 11:21 AM UTC

I think its pretty clear that someone could come up with some sort of device that might take over the plane avionics.

A lot of planes have avionics systems that are, to put it quite blunt, not secure from tampering by a determined foe.

There isn't enough work done to secure a lot of the systems on planes from intrusion/hacking, and in some cases its quite feasible that someone using a self-made device could do dangerous things to an aircraft during flight. There are plenty of radio devices that can be modified or simply used to interfere with avionics and navigation/comms equipment, and in many cases these devices are indistinguishable from average consumer products in design.

So I think its only fair that a general blank policy be put in place. They're not really trying to prevent you from using your cell phone; they're trying to prevent the terrorist who has a $200 radio modified for jamming/confusion purposes that looks like a cell-phone.

Re: Fliers Must Turn Off Devices, but It’s Not Clear Why

#230

Post by DaniFong » Mon, Nov 28, 2011, 11:27 AM UTC

artursapek wrote: post #129

DaniFong wrote: post #113

Earlier quoted context omitted.

Out of genuine curiosity, why is it ridiculous? Stolen time is stolen time, no?

All you do your entire life is what you're confined to doing on an iPad in an airplane? It's not that huge of a loss. You're not dead for half an hour on each flight.

Haha, you make a good point.

Nonetheless, flying could be an amazing experience. But fliers are some of the least happy people because they are treated either like criminas, children, or cattle. If the time isn't quite stolen, it is at least spoiled.