Previously posted on the Huffington Post

Hi! My name is Eric, and like a number of the bloggers in the new Huffington Post Science section, I'm a scientist. An astrophysicist, to be exact. Unlike many of [url=http://www.huffingtonpost.com/saul-perlmutter[/url]them, I've never won a Nobel prize. Even if I find ET, someone else will get the prize. It doesn't bother me much. Not having a Nobel means I don't have to talk about big picture stuff or seem particularly wise. It also means I can put an equation in my post. Like all scientists, I like beer, football, and explosions. But we can talk about media stereotypes of scientists in a later blog. We can also explore issues from the Big Bang Theory to The Big Bang Theory. And we'll talk about life on other planets and life on the only planet where we know it exists. We'll talk about climate change, and how to tread water while waiting for the rescue boats.

Last week, I was in a hotel lobby reading the USA Today. Like 95% of Americans, I only read the USA Today when I'm staying in a hotel. That factoid was on the cover. When I got to the letters section, I found a heated discussion was about Alec Baldwin being put off an airliner for using his cell phone and the arguments were about whether a cell phone could down an airliner. Opinions ranged from "a cell phone can't effect an airplanes instruments" to "there have been cases of navigation errors due to cell phones."

One fun part of being a scientist is you don't have to know the answers to questions. Even if you can't get an exact answer, you can make an estimate based upon facts you do know. In my business, one of the most famous examples of such an estimate is the "Drake Equation" which an astronomer named Frank Drake came up with in 1961 to estimate the number of civilizations in the Galaxy with which we could potentially communicate. It looks like this:

N = R* fp ne fl fi fc L

It's got stuff we don't know on the left side (number of communicating civilizations) and on the right side things we might possibly know some day like the Galactic star formation rate and the average number of earth like planets per star. I won't go into more detail because we've been talking about that equation for 50 years. Maybe later. But scientists use similar equations all the time. So with no further ado I introduce you to the "Baldwin Equation." (First rule of science: when your equation is talking about hundreds of potential deaths, name it after someone else. Alec can always claim its about Billy.) Here's the Baldwin Equation.

Nc = Rf np fph fon pc

It's pretty simillar to the Drake Equation. Nc is the number of crashes per year caused by cell phones. Rf is the rate of airline flights (flights per year, about 10.4 million), np is the number of passengers per plane (an average of 264), fph is the fraction that have cell phones (somewhere around 90% in U.S.). fon, the fraction of cell phones that are left on during a flight, is a different story. I don't know of any studies that say what that fraction is, so we'll have to go on my mostly subjective impression. I've noticed that smart phones are very likely to be left on, probably because they take a long time to start up. I only remember one time that I saw someone actually turn an iPhone off on a flight. This includes flights where the flight attendants explained the process for turning off an iPhone. I've also never seen anyone turn off an iPad.

On the last flight I took, among the 12 people in my row and the row ahead I counted 10 cell phones and four got left on. The guy sitting next to me turned up his ringer and put in the seat pocket. I guess he was expecting an important call. Apparently nobody told him that his chances of successfully receiving a call at 38,000 feet are very small. Anyway, that's 40% of the phones being on.

The product of those terms, 1 billion, is an approximation of the number of cell phones that fly in the U.S. annually in a powered on state. pc which we haven't defined, is the probability that a single cell phone will cause a crash. We don't know what pc is, other than that is isn't a big number or planes would be falling out of the sky, and that it probably isn't zero. If we assume that nothing has changed in the number of phones flying in the last 5 years, we can say that it's likely that pc is less than one in 5 billion. If you put that number in for pc you get a crash every 5 years, which we haven't had.

So what has this exercise told us? Your cell phone is very unlikely to cause a crash. But lets look at it from the FAA's perspective. They don't know what pc is either, and they have to worry about the effects of billions of phones. One of those billions of phones may have been dropped or gotten hit with a cosmic ray in a way that makes it broadcast on the wrong frequency. But you say "The chances of that are a billion to one!" With two billion phones flying annually, that would be two crashes a year. The probability of a crash increases with the number of powered on phones, and for the FAA the only acceptable number of crashes is zero. That means no powered on phones, and hence the rule. If they drop the rule, the risk of a crash triples, and if pc is high enough, that could mean a crash a year.

What does that mean for Alec Baldwin? Well, I lied to you. Alec Baldwin didn't get kicked off a plane because his cell phone was on. Alec Baldwin got kicked off a plane for not following the instructions of a flight attendant. Imagine if everyone on a flight decided that they didn't need to follow flight attendant instructions. We've all felt singled out on occasion, if we've flown enough. My prescription is to apologize, do what I'm told, order a drink when I can, and complain to friends later. There's a time and place to fight, and fighting a flight attendant on an airliner is never the time and place.

What does it mean for you? It means that there is a very, very, very small chance that the seven seconds it takes to turn off your phone and the 30 seconds it takes to turn it back on could save 300 lives. Is 37 seconds too inconvenient? The cost to passengers is 37 seconds when they are trapped on an airplane, anyway. And please don't turn it back on until the wheels are on the ground and you've left the runway. In order to keep certified for automatics landing, the crew might be letting the plane land itself. In other words computer might be landing the plane by following radio signals. The last thing you want is a bunch of frequency hopping transmitters splattering signals all over the spectrum when you're a few hundred feet up. If a cell phone can crash a plane, that would be when.

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@SETIEric@qoto.org (Mastodon)

Right on Eric! I get asked the same question a lot. (I make my living testing airplanes, and things like how cell phones might effect them.) A lot of people don't like what I tell them. You are correct that the odds of a bad result are small, but the consequences of said bad result can include 300 people (including yourself) dieing in a fiery crash. I'm always amazed that some people actually think it should be there choice if they die in a fiery crash or not. Don't the other 299 people get a vote? In my opinion, each of them gets a veto.

So the next time I get rude with people in those situations (the possibility of a fiery death always brings out the worst in me), I will send them to your blog.

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Heck with the instruments.

Every single one of us has heard a cell phone buzz in a radio or speaker. Want the captain to miss the urgent call from the tower to hit the brakes because another plane is screaming down the runway?

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Good point.

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@SETIEric@qoto.org (Mastodon)

Actually, a buzz on voice coms is pretty benign. The pilot hears the buzz, and asks for the message to be repeated. The real problem is subtle changes in other indicators. Like when the little needle that SHOULD say turn 5 degrees left to avoid running in to a mountain instead says turn 5 degrees right.

There have also been a few so far unexplained cases of digital autopilots briefly going crazy. Things like commanding full left wing down or full nose up for a second, then going back to normal. No faults found (as we say in the business), and the results can't be duplicated. Maybe cosmic rays, maybe man-made interference.

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The arguments presented in the blog are a little misleading, and the conclusion is way way off.

The chances of a cell phone causing noticeable electrical equipment interference is far less than 1 in a billion. Additionally, the risk of even a noticeable error causing any loss of life is further greater.

Everything in thing in this world is a cost/benefit analysis. The FAA has no issue with banning cell phones on planes because there is no benefit to them, and so even though they can't quantify the risk, they maintain their ban.

As a society, we must recognize that even extremely tiny costs distributed over hundreds of millions of people, still add up to something material. Maybe 1/10000 people miss a very important call? Maybe that piece of information, being delivered and digested several hours before their arrival, will change their decisions and materially change people's lives. Perhaps a manager won't fire someone, perhaps a financial transaction will be cleared, etc...

So what is the right cost/benefit balance? It's not nearly as simple as Eric suggests - and I disagree that people who refuse to comply are being rude. In my personal opinion and my vague understanding of the statistics involved, the costs of the ban outweigh the benefits of compliance.

...but that brings me to my conclusion: The reality is that several years of rampant non-compliance with the rule has demonstrated to people (incorrectly or not) that the risk is nil - and there's no way for the FAA to change that at this point. Given that, the FAA needs to focus on shielding electronic equipment to prevent this from even being a possibility. What's more, is that I believe the FAA has already done that, and that equipment is already adequately shielded, and that the ban on cell phone use only still remains simply because no one in authority has anything to gain by lifting it.

This "no cell phones in planes" policy is likely 100% useless and a relic of a system that cannot change.

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As a society, we must recognize that even extremely tiny costs distributed over hundreds of millions of people, still add up to something material. Maybe 1/10000 people miss a very important call? Maybe that piece of information, being delivered and digested several hours before their arrival, will change their decisions and materially change people's lives. Perhaps a manager won't fire someone, perhaps a financial transaction will be cleared, etc...

Perhaps people need to get some perspective.
Perhaps the material change from that earlier decision results in a change for the worst. Perhaps the manager will decide to fire someone. Perhaps the transaction being cleared shouldn't have been?
Perhaps, perhaps, perhaps.
Perhaps it would be better to err on the side of safety. If a business relies on staing in contact with it's people 24/7, it's not a very good business model. They have to sleep sometime.

Business isn't all important. Living is.

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Grant
Darwin NT

Previously posted on the Huffington Post

A very enjoyable read, Eric. And it reaffirms my stance that as long as there's Greyhound, Amtrak and horses, I won't be part of the equation.

A quote from a recent NY Times article:

"One crash in which cellphone interference with airplane navigation was cited as a possible factor involved a charter in Christchurch, New Zealand, in 2003. Eight people died when the plane flew into the ground short of the runway.

The pilot had called home, and the call remained connected for the last three minutes of the flight. In the final report, the New Zealand Transport Accident Investigation Commission stated, “The pilot’s own cellphone might have caused erroneous indications” on a navigational aid.

Since 2000, there have been at least 10 voluntary reports filed by pilots in the United States with the Aviation Safety Reporting System, administered by NASA. In 2007, one pilot recounted an instance when the navigational equipment on his Boeing 737 had failed after takeoff. A flight attendant told a passenger to turn off a hand-held GPS device and the problem on the flight deck went away."

I agree that Eric's quantification of this issue may be questioned, but the fact remains that the possiblity is non-zero. As long as there is a non-zero possibility of my being involved in a fiery crash I will continue to be rude to people who use banned devices on airplanes I ride in. You have all been warned.

Added in edit: here is another interesting article on the subject.

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Perhaps people need to get some perspective.
Perhaps the material change from that earlier decision results in a change for the worst. Perhaps the manager will decide to fire someone. Perhaps the transaction being cleared shouldn't have been?
Perhaps, perhaps, perhaps.
Perhaps it would be better to err on the side of safety. If a business relies on staing in contact with it's people 24/7, it's not a very good business model. They have to sleep sometime.

Business isn't all important. Living is.

I believe that on average people make better decisions with more information than with less. Conversations via cell phones provide information, and it could be personal or business. Additionally, business decisions can affect thousands of lives. I hire and fire people every month - if I make the wrong decision because I'm missing some key piece of information, that affects people's lives in a very meaningful way.

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A quote from a recent NY Times article:

"One crash in which cellphone interference with airplane navigation was cited as a possible factor involved a charter in Christchurch, New Zealand, in 2003. Eight people died when the plane flew into the ground short of the runway.

The pilot had called home, and the call remained connected for the last three minutes of the flight. In the final report, the New Zealand Transport Accident Investigation Commission stated, “The pilot’s own cellphone might have caused erroneous indications” on a navigational aid.

Since 2000, there have been at least 10 voluntary reports filed by pilots in the United States with the Aviation Safety Reporting System, administered by NASA. In 2007, one pilot recounted an instance when the navigational equipment on his Boeing 737 had failed after takeoff. A flight attendant told a passenger to turn off a hand-held GPS device and the problem on the flight deck went away."

I agree that Eric's quantification of this issue may be questioned, but the fact remains that the possiblity is non-zero. As long as there is a non-zero possibility of my being involved in a fiery crash I will continue to be rude to people who use banned devices on airplanes I ride in. You have all been warned.

Added in edit: here is another interesting article on the subject.

A couple of things...

1) I agree the risk is non-zero. However, frankly, that isn't a meaningful statistical statement. Nothing is non-zero. Moreover, we take many many non-zero risks every single day, risking not only ourselves, but our families, friends, and bystanders around us.

All you need to do is get in a car, and you are putting many people at non-zero risk. We do it anyway because the quality of life benefits outweigh the risks.

2) The incident in NZ in 2003 occurred with an active cell phone call in place in the cockpit itself, right next to the navigation equipment. Given the inverse square rule for interference, it is very different from a device in the cabin. The only other recorded instance was not a cell phone but a large handheld GPS device.

Conclusion) My point is only this. The interference may indeed be a real risk, but given the common non-compliance with the rule (in fact, total compliance isn't really practical), then the equipment needs to be redesigned to increase shielding. If there is a real risk we simply cannot count on people to turn off all their equipment (whether they didn't intentionally or not).

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Hi Mario,

I think we're going to see a compromise in the very near future, similar to what was done with wifi in flight. Basically cell phones will be allowed through an on-board relay when the aircraft is above 10,000 ft MSL. That greatly reduces the risk of navigation errors causing more than annoyance. I think we'll still see demands that cell phones be powered off before the aircraft door is closed. Instrument landings will continue to be the danger phase for radio emissions.

My understanding is that the cause of the delay in on board cell phone relays is that there's not an easy way for the airline to get paid for its use. (I have a cell signal booster/relay, and anyone in range can use it for free. For an airline, that probably won't do.)

Has anyone noticed that the discussion here is much better than what's happening on HP?

Eric

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@SETIEric@qoto.org (Mastodon)

Hi Mario,

I think we're going to see a compromise in the very near future, similar to what was done with wifi in flight. Basically cell phones will be allowed through an on-board relay when the aircraft is above 10,000 ft MSL. That greatly reduces the risk of navigation errors causing more than annoyance. I think we'll still see demands that cell phones be powered off before the aircraft door is closed. Instrument landings will continue to be the danger phase for radio emissions.

My understanding is that the cause of the delay in on board cell phone relays is that there's not an easy way for the airline to get paid for its use. (I have a cell signal booster/relay, and anyone in range can use it for free. For an airline, that probably won't do.)

Has anyone noticed that the discussion here is much better than what's happening on HP?

Eric

Yep! ;)

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I Desire Peace and Justice, Jim Scott (Mod-Ret.)

My guess is that the subject of "errors" should be regarded as a scientific subject field on its own if it is not so already. It possibly covers a broad field, having quite a variety of angles and possibilities.

One such example is error handling in software as well as human errors. Computers and other machines are known to be making errors on their own at times.

Typographical errors and other similar errors may be corrected by means of error correcting software. If a computer (PC) or more likely a car breaks down, it typically ends up at the car workshop where its broken part or parts become replaced by new working parts.

At the high end of the spectrum, some errors being observed may be the result of the human brain or mind and its capabilities at detecting its surrounding environment. Sometimes it may be more to certain things than what is readily apparent at first glance or observation.

And a little edit on this: We have on these web-pages (apparently in the Science Forum) a discussion about the so-called Higgs Boson (or God Particle).

Maybe it could be possible to derive or make some type of conclusion whether there exists some kind of relationship between these two different subjects?

Has anyone noticed that the discussion here is much better than what's happening on HP?

Shocker.

Another $0.02 -

I am completely willing to live with the "danger" that an errant cell phone will cause a plane to crash and I will burn to death horribly and I do, in fact, live with that "danger" every time I get on a plane.

There are an *incredible* number of parts on a jetliner and more than one of them is rather critical to keeping me from dying in a fiery furnace of horror. A person could say that all this stuff is unnecessary to flight. We could go back to mechanical controls -> you know, steel cables and things <- and then we wouldn't have all those non-zero risks we take.

As long as their is ONE chance in a billion that a fuselage might crack open and suck a stewardess out of the plane, we either ought to fly below 10,000 ft and make her wear a parachute or we should outlaw "flight attendants."

Now, having tried to put a little perspective on the idiocy of climbing into a bucket of parts maintained in some Central American country where the mechanics don't read English and the manuals are printed in English... not to mention the non-zero risk of being struck by lightning or a meteor in flight, and then worrying about the chances that a cell phone could cause a plane to crash, I just want to say this:

I hope they keep the cell phone ban. I LOVE the excuse to turn that #$%@ thing off. Not only do I not want to try to talk to someone during the flight, I don't want to hear other people talking on their phones at high volume speaking like people speak these days:

"Did you hear what ___ she did? Yeah, apparently she ____ him and then told him to ______. I don't know what the _____ you think about that _____, but I ____think that she's a _______ ________ ________ and smells a bit like old cheese. ______!"

I kinda LIKE the noise on an airliner. I get to read or do a crossword puzzle in that solitude. When someone does speak to me my usual response is, "What?" until they give-up and start reading the trash they bought in the magazine store.

And YES, it is sometimes just unbelievably important that someone can get in touch with me to do their business right-now! So my voicemail tells them who to call in my absence. It's amazing! Somehow, if they have to call an 800 number, that emergency can always wait until I land somewhere and check my voicemail.

I'm old enough to remember when nobody turned off their cell phones when they got on a plane. They drank coffee out of ceramic cups, cut their meal with a sharp metal knife, and SMOKED in the back of the plane, and used Zippo lighters on a PLANE, and they even queued-up for the lavatory near the cockpit!

Oh my god, it was like... it was like playing Russian Roulette.

How I remember that we used to scream and scream and scream the whole time we were in the air.

SNAP OUT OF IT, PEOPLE! YOU'VE BEEN MORONOFIED.

The problem with the non-mathematically inclined population (i.e. some 99% of it), is that very small non-zero probabilities are either perceived as zero (my cell phone isn't going to crash the plan) or as one (I'm going to win the lottery).

Very enjoyable read, Eric.

And the difference in discussion might be due to the fact that everybody here believes that small probabilities exist, or we wouldn't be here, looking for ET's comms.

Tbret, most of the other "possibilities" you describe are quantified. Risks are accepted in the certification and operation of aircraft, based on this quantification. For example, based on this we DON'T make passengers wear parachutes (that will probably just change how you die in a serious situation), but we DO ban smoking in the loo (that regularly killed people in the Bad Old Days). The difficulty with cell phone EMI is that is not yet quantified. It may never be quantified, since phone technology and usage change so fast.

Yes, it might be decades before random cell phone usage is confirmed as the cause of a fatal accident. Does that make it OK to kill that next plane load of people, when it can very easily be prevented?

Good for any of you if you are willing to be a guinea pig in the search for answers. Just be sure to check with everybody else on the aircraft first. They may not share your spirit of adventure.

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While I completely agree with any measures in place to minimizes risks, I do not completely understand the reasoning behind the idea that cell phones might be dangerous to aircraft operation.

Cell phones are relatively low-powered radio transmitters, even at their maximum output power - I think it's 2 Watts for GSM handsets, and much less for more recent technologies. One would think that aircraft capable of flying through thunderclouds are supposed to be able to deal with electromagnetic fields of relatively minor magnitudes.

Moreover, it is very unlikely that a cell phone will be able to receive a signal except close to takeoff/landing. According to my knowledge, cell phones do not transmit at all while out of coverage.

The famous 'GSM buzz' that was already mentioned is also unlikely to be a problem, because it has a very short range and newer technologies don't cause similar interference at all.

In 2007, one pilot recounted an instance when the navigational equipment on his Boeing 737 had failed after takeoff. A flight attendant told a passenger to turn off a hand-held GPS device and the problem on the flight deck went away.

This simply is not possible. Reminds me of an instance where a patient of mine told me to turn off the navigation system of my ambulance car because he feared negative effects by electromagnetic radiation. However, GPS devices don't transmit. They only receive (very weak) signals from the GPS satellites and do not cause any radiation at all.

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However, GPS devices don't transmit. They only receive (very weak) signals from the GPS satellites and do not cause any radiation at all.

Any conductor carrying a time varying voltage is a transmitter. Digital systems can react to extremely low strength radiated fields, if the frequency matches an internal frequency (or its harmonics). For more information, sign up for my EMI/EMC lectures at ITPS Canada.

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