Monday, November 28, 2011

Blowing a Circuit Over Everybody's Expertise

I'll be the first to say that all those people who know about circuit boards and microprocessors are pretty darned clever. But don't let them wander too far from their field of expertise or they wind up making statements that make them sound, well...stupid

I'm referring to an item that ran in the Bits blog of The New York Times online on Sunday headlined, Flyers Must Turn Off Devices, But its Not Clear Why, in which the author, Nick Bilton, disses the safety hazards associated with the use of personal electronic devices on airplanes and cites as the expert, the association representing wireless device manufacturers. 

What fries me about the hew and cry that accompanies this issue each time it is brought up is that people smart enough to be downright boring at a dinner party explaining digital complexities can lift up their eyes from the screen of their iPad and see something like commercial aviation in such starkly simplistic terms. 

Bilton's story boots up with the argument that people routinely do not turn off their devices on airplanes and no planes have crashed. Therefore, no problem exists. There are two problems with that. The first, is that it is wrong. The history of the study of the effect of EMI on airplanes begins with a spectacular mid-air collision - over New York no less - in 1960. At that time it was thought that radio interference caused the pilots of a United DC-8 to believe their VOR receiver was not working, resulting in the plane being off course and colliding with a TWA Super Constellation. 

Since then there have been other accidents studied by the members of the RTCA committee which has been investigating the potential for gadgets to interfere with airplane systems. When I wrote about this for the Times in January of this year, one of the  members mentioned several accidents (some of them quite well known) in which EMI was considered a likely contributing factor. Electromagnetic interference, unlike bent metal or broken parts, leaves no trace. 

Still, there have been many reports of pilots experiencing problems in the cockpit that did not lead to disaster that were were tracked back to a passenger using an electronic device. You can read more about them here.

But the second and larger problem with the story is that it is another rallying cry for air travelers who don't get that aviation accidents aren't an A-follows-B sort of thing, like plugging a fork into a wall outlet and watching the fireworks begin.  Absent a plane-spiraling-to-earth-event, everyone armed with a Google-equipped iPod (forgive me, Android) now feels that is perfectly appropriate to to make their own decision about whether to heed the flight attendant's plea to kindly power down anything with an ON/OFF switch.  A lack of accidents is not evidence of air safety and its frightening that passengers feel equipped to make safety decisions on their own with this yardstick as measuring device. 

Bilton brings his argument on home by quoting an executive of the International Association for Wireless Communications, a trade group representing the device manufacturers, hardly an unbiased source. The executive reassures Times readers that aircraft wiring is shielded. Well, yeah. We know that. He does not suggest the impact of 200-400 plus passengers, each with 2 to 3 devices all powered up and ready to go may be slightly beyond what any airplane designer may have had in mind a decade or more ago when the PED wasn't SOP for everyone over the age of 3. We're not even talking about the thousands of airplanes in service around the world that were designed prior to the 1990s. 

Anyway, I'm not feeling so good about the integrity of all that communications gear or even the robustness of the shielding of airplane wiring, which will always be one or two digital generations behind the device manufacturers. (I say this having spent five years on an F.A.A. committee on aging aircraft wiring. See me later.)

So when I get on an airplane and I am mildly tempted to keep my Kindle on, or squeeze a few more photos on my digital camera, I resist that temptation. To steel my spine I need only remember the what Boeing had to say about the matter. 

"Operators of commercial airplanes have reported numerous cases of portable electronic devices affecting airplane systems during flight. These devices, including laptop and palmtop computers, audio players/recorders, electronic games, cell phones, compact-disc players, electronic toys, and laser pointers, have been suspected of causing such anomalous events as autopilot disconnects, erratic flight deck indications, airplanes turning off course, and uncommanded turns. Boeing has recommended that devices suspected of causing these anomalies be turned off during critical stages of flight."

Digital blogger or Boeing guidance? For me, it's not a tough call.


Capt Russ Williams FRAeS said...

Congratulations - an excellent article on the potential hazards of using mobile telephones in flight. The UK CAA had to ban their use in the mid 1990s because of the increasing numbers of air safety incidents being reported at the time. More recently there was a case of a B747 experiencing all four engines increasing power on three separate occasions and having to be throttled back each time. This was followed by the aircraft turning right when the program had initiated a left turn and all because one businessman was refusing to switch off his mobile and was insisting on trying to make a call. Many years ago the JAA issued a Temporary Guidance Leaflet suggesting there should be monitoring equipment on board to ensure all such devices are turned off and until EASA in the EU initiate such action, incidents will continue.

Patrick Smith said...

Interference from a phone is suspected in the crash of a Crossair (Switzerland) regional plane about ten years ago. A majority of the accounts of interference are anecdotal -- but not all of them, and while we are LIKELY erring on the conservative side, there's a lot we're not sure of.

Meanwhile, judging from the reader comments that followed the Times story, people don't seem to understand that the prohibition against using laptops during takeoff and landing isn't about interference, it's about keeping laptops from becoming 200 mile-per-hour projectiles during an impact, or from hampering a sudden evacuation. A computer is a piece of luggage, and a potentially deadly one during an emergency.

The same holds for iPads and Kindles. Sure, a book can weigh as much as a Kindle, but this is where they've drawn the line.

Many passengers seem to believe it's all or nothing; either we permit every electronic device, or ban them all. But it's not so simple.


Unknown said...

Thanks for the article Christine. Please do something about the "Myth Busters" recently aired episode that says that this is all a myth! I could not believe it, very bold and irresponsible from them. I wrote them a letter, but I believe you might have more pull than I :)

Christine Negroni said...

Thanks for your comment, Gabe. Wrote about mythbusters a while ago. Read it here.

Anonymous said...

I am an airworthiness inspector with one of the largest and most respected regulatory agencies in the free world. I have experienced incidents in aircraft cockpits when the captain asked the lead flight attendant to survey the cabin for someone using an electronic device as were taxiing out prior to takeoff. We sat on the taxiway until the culprit was located - a passenger who indeed was using a cellphone. I have been privy to accident reports on two 737 crashes; in both incidents, at least one of the investigators was convinced that RMI was one of the major contributing factors. Myth Busters is an entertainment program - certainly not a source of legitimate testimony regarding issues like flight safety. But the use of electronic devices is also a discipline thing, i.e., most people feel it impinges on their right to be told they can't do something. They will do what they want regardless of the consequences.

Julio Afonso said...

Totally agree with this post,
I recently flew from Germany to Manchester and despite the request from the cabin crew, one passenger apparently had the need to use his Laptop with a internet dongle to watch an episode of of a TV reality show on I what I believe was the BBC iplayer and he was sure that it would not interfere with the electronics on the airplane.

How about some common sense?.
People should stop being stupid and think that their actions will affect others.

Anonymous said...

Great post. With the potential catastrophic consquences of erring to the wrong side of this issue, regulators cannot let financial considerations cloud the issue. Clearly more dangerous to air navigation than person electronic devices is LightSquared's insistance that it be allowed to implement its Near-GPS upper L-Band frequency wireless network. Its still is trying to push forward in spite of the disastrous results of GPS interference tests. How much money is it worth to potentially comprimise the guidance of military ordinance and almost all air navigation. Why is it even being considered until NO interference is conclusively demonstrated?

Anonymous said...

I wanted to tell you that your response to the article in the Times about electronic devices was excellent. Air travel can be so unpleasant these days that people just turn off their brains and leap to such unreasonable conclusions. As in, "I forgot to turn my phone off one time and we didn't crash, so the ban is stupid."

Anyway, I wanted to tell you that I really enjoy your writing. You do
a wonderful job and I hope you continue for a long time. And I just changed my mind about your was MORE than excellent.

Majeed Panahi said...

As a pilot , and a person with background in electronics , I find it difficult to buy the scaremongering theories of electronics and the doomsday scenarios of falling aircraft due to use of personal electronic devices on board.

I am not going into the technical details and frankly , I would not like to judge on technical issues without having a first hand and close look on them before I publish anything in a professional thread.

Facts are clear. The aircraft cockpit itself is full of electronics and electronic emitting devices. Anyone who believes in the dangers of electronics interferences, and who has a chance to go down to the E&E compartment normally underneath the cockpit , will probably get a shock seeing all those countless electronic racks controlling devices that control the whole of the aircraft systems ( including flushing the toilets).

All of those devices and circuit boards have the capabilities of creating radio interference although their shielding is of a high quality. That is all in theory , the reality is that interference does occurs but nowhere near the levels to put a state-of-the-Art flying machine in a noise dive to disaster.

I am not even going to mention the electronic signals that litter the atmosphere that the aircraft flies in with a wide frequency spectrum that could create interferences with the Aircraft avionics and electronics.

If , and that is a hypothetical situation , the use of electronic devices really creates a danger for the aircraft and its occupant, then the industry is obliged and accountable. We simply should not fly if these machines are so vulnerable and I strongly believe that we need a much better defenses than a mere PA to passengers to switch of their devices..

In Aviation , 1 chance in a million requires action by manufacturer and regulators. If there is a real threat , then then we are exposing peoples life and property to danger.

As a pilot , I had no issue with the implementation of that rule, but when asked by many passengers , I told them what I am basically saying here.

Anonymous said...


First, I would never get on an airplane with you as the pilot. Your obvious lack of common sense scares me. I, too, am a pilot. And an electrical engineer who has studied RFI and served on the RTCA Special Committee that studied this matter. Your unsubstantiated claims are dangerous and undermine passenger safety. Shame on you.