Effect of electronic devices

[phil gollin]

I don't know if this belongs here or elsewhere, however, from the internet version of The Daily Telegraph ;

Airlines blame mobile phones for instrument problems - Telegraph (http://www.telegraph.co.uk/technology/news/8574679/Airlines-blame-mobile-phones-for-instrument-problems.html)



Airlines blame mobile phones for instrument problems

Mobile phones and other electronic devices have disrupted flight instruments 75 times over six years, according to a confidential report prepared for the aviation industry.


By Christopher Williams
11:57AM BST 14 Jun 2011
http://www.pprune.org/template/ver1-0/i/share/comments.gif46 Comments (http://www.telegraph.co.uk/technology/news/8574679/Airlines-blame-mobile-phones-for-instrument-problems.html#disqus_thread)

Pilots and crews told the International Air Transport Association that between 2003 and 2009, mobile phones, iPods, laptops and other equipment all caused problems.


A total of 26 of the incidents affected flight controls, including the autopilot, autothrust and landing gear, according to ABC News.


A further 17 reports concerned navigations systems, there were 15 incidents of interference affecting communications systems and 13 triggered warnings including “engine indications”.


During one flight electronic devices are believed to have caused the autopilot to disengage at 4,500ft.


The report says: "“The autopilot disengaged by itself and the associated warnings/indications came on. [Flight attendants] were immediately advised to look out for PAX [passengers] operating electronic devices,” the report says. “[Attendants] reported that there were 4 PAX operated electronic devices (one handphone and three iPods).”



After an announcement telling passengers not to use their electronic devices, “for their safety and the safety of the flight” the flight continued without any further incident.

The IATA report stresses that it does not verify that electronic devices caused the problems, however, but records the impressions of pilots and crew. Mobile phones are believed to have been responsible for 40 per cent of the incidents.

In another incident it’s claimed a GPS unit in the cabin gave an incorrect reading because two laptops were being used nearby. Electronic interference was also blamed for rapidly changing altitude measurements on a separate flight. Passengers were asked to switch off their devices and the readings returned to normal.

“After an hour, changes were noticed again… Purser made a second announcement and the phenomena stopped,” the report says.
The claims will stir the debate over the use of electronic devices on flights. Some experts believe the rules are overly cautious.

“There is a lot of anecdotal evidence out there, but it’s not evidence at all,” John Nance, a former commercial and Air Force pilot, told ABC News.

“Its pilots, like myself, who thought they saw something but they couldn’t pin it to anything in particular. And those stories are not rampant enough, considering 32,000 flights a day over the U.S., to be convincing.”

The UK Civil Aviation Authority has found that electronic interference from phones can lead to “errors” on instrument displays and create noise on pilot radios, however. Boeing said the problems could be particularly severe on older aircraft whose instruments are not well shielded.

The use of mobile phones on aircraft was banned until 2008, when the communication regulator Ofcom agreed that carriers could offer coverage above 3000ft. Several airline including BA, Emirates and Ryanair responded by launching services costing up to £2 per minute for voice calls. American carriers have also launched in-flight WiFi services.

[green granite]

I think it's a bit like hospitals, your phone will cause people to die as it interferes with equipment, so turn it off....................doctors phones, on the other hand are perfectly safe and can be used at all times. :)

[ExSp33db1rd]

So what's new ?

The 707 had the compass fluxgate device ( that provided the magnetic heading reference ) behind the lining of the First Class hatracks (overhead stowage in todayspeak) because, I believe, putting it out on the wing which was more desirable, caused problems due to wing bending motions, or so we were told.

Experiencing navigation problems one day, I was asked by the Captain to check the hatracks, which bore a prominent notice stating that electrical devices must not be stowed between two very obvious marks painted on the edge of the hatrack about a yard apart.

I found a bag containing a tape-recorder, one of those devices about the size of a Remington typewriter, that used reel-to-reel tape on big drums but was what passed as a "portable" tape-recorder in those days positioned precisely in the forbidden area, and the permanent magnet in the loudspeaker of this device was deflecting the Port side compass system.

Removal of same - I refrained from opening the door and tossing it out - corrected our problem, and ensured that the Captain steered the course that I, the Navigator, suggested.

Nothing new under the Sun.

[sitigeltfel]

I think it's a bit like hospitals, your phone will cause people to die as it interferes with equipment, so turn it off....................doctors phones, on the other hand are perfectly safe and can be used at all times. :)

When I was last in an NHS hospital they had given the contract for pay-phones to a private company who were charging extortionate rates to make outgoing calls. The ban on mobiles was probably, at least party due, to protect the companies investment.

[Speed of Sound]

The ban on the use of mobile phones on aircraft and in hospitals was done for commercial reasons in both cases.

No electronic medical equipment or aircraft avionics would be certified for use if there was any chance that their operation could be affected by mobile phone use. And an autopilot disengaging and a CC subsequently finding four people using hand held devices is NOT evidence.

[Denti]

Well, digital net (GSM, 3G) cell phones were simply not around when the current bread and butter airliners were certified, so there was nothing about them in any certification test.

If you want to certify on board cell phone service with a pico cell or WLAN you have to prove that there are no interferences with the onboard system, especially navigation and flight control systems. And indeed some series of the 737NG display system did malfunction with an onboard WLAN network.

[Pub User]

No electronic medical equipment or aircraft avionics would be certified for use if there was any chance that their operation could be affected by mobile phone use

Really? What about the thousands of aircraft still flying, which have been around since mobiles were but a twinkle in Mr Nokia's eye?

Is your 'phone call really worth the risk of someone's hospital treatment being compromised, or an aircraft being put in danger?

Don't be selfish, TURN THEM OFF.

[sabenaboy]

Gentlemen,

I would think that on almost every flight today there are several passengers (and pilots :E) "forgetting" to switch off their mobile, Ipad, laptop etc. So I suppose that if the dangers were that big, some real proof about adverse effect on the safety of flights would have appeared by now if there were any.

But I agree that switching these devices off harms nobody and therefore switching them off is a good idea, but please don't dramatize...:ok:

[The late XV105]

Bang on the money, sitigeltfel. Banning mobile telephones in NHS hospitals is entirely down to protecting the commercial interest of the third party provider (that still ran up a whacking great loss despite the high call charges). I've had this said to me by several hospital execs. Last year on the other hand I spent three days in a Nuffield hotel - sorry, hospital - and could use my mobile telephone as much as I liked.

I have had two conversations with fuel station owners about the ban of using mobile telephones on forecourts; I don't do this simply because it is a serious distraction whilst dispensing volatile liquid and it seems this is exactly what they are interested in, not an ignition source from EMF.

Several conversations with electronics engineers in the aviation industry gave the view that banning mobile telephones was also more down to distraction in a potentially dangerous environment, and consideration for those around. The first of these fits quite well with permitted usage on some carriers today at 3000+ feet agl.

Out of interest; I accidentally left my smartphone switched on all the way from LHR to SIN last year and (to my surprise given FL380 at the time) had "welcome to Vodafone Poland" to prove it when I arrived at my destination!

[Piper_Driver]

As an electrical engineer that has had to deal with RFI issues extensively in my career I am in full agreement that the devices should be switched off. The problem is that while a properly working device will have little or no emissions, a device that has been damaged can have significant emissions with no external indications.

Cell phones, laptops and other portable equipment are subject to dropping and other abuses. These abuses can damage components that are critical in suppressing spurious emissions. The devices may appear to operate perfectly normally or have minor issues such as poor range or reduced battery life. In the meantime they can radiate like crazy!

Better safe than sorry. Turn them off, I do.

[FlightPathOBN]

Boeing just did a short piece on this, going into the radar testing room, to show the emissions from a cell phone, and how some are over the limit and could affect equipment, and that some can get into synch with each other and amplify the waveform.

Most people dont understand that the sensors are all over the aircraft, not just up front.
Boeing explained that the newer aircraft, and ones that have advertised WiFi service, have been shielded....

[Brian Abraham]

From Avweb, bolding mine.

AVwebFlash Complete Issue (http://www.avweb.com/eletter/archives/avflash/1930-full.html)

Report Suggests Cellphone Interference Happens

An International Air Transport Association report suggests cellphones and other personal electronics, notably the iPad, can cause alarming disruptions to aircraft systems. The report, obtained by ABC News, is said to document 75 instances between 2003 and 2009 in which flight crews believed interference from passengers using an electronic device caused something to go wrong with the aircraft. Anomalies ranging from autopilots disconnecting to a clock that ran backwards were said to disappear when the electronics were shut off. The report is getting mixed reviews from those who study aviation safety.

John Nance, author and former commercial and military pilot and ABC's own aviation analyst, dismissed the report as a collection of anecdotes that prove nothing. "There is a lot of anecdotal evidence out there, but it's not evidence at all," said Nance, "It's pilots, like myself, who thought they saw something but they couldn't pin it to anything in particular. And those stories are not rampant enough, considering 32,000 flights a day over the U.S., to be convincing." But Dave Carson, of Boeing, the co-chair of a federal advisory committee looking into the issue, said tests have proven onboard electronics can produce signals that are over what Boeing considers to be the safe limit for avoiding interference. Blackberry and iPhone cellphones were both over the limit but an iPad produced signals that far exceeded the standards.

[aveng]

I was once called to the flt deck of a 737 classic for an "autopilot issue" - when i got there both course windows were going nuts and the course pointers on both HSI's were also going nuts. I tried a few resets to no avail. Then I was about to leave the cockpit to consult the books and saw a passenger talking on his mobile in the forward galley (right above the electronic compartment). When we asked him to end his call and turn off his mobile all probs ceased immediately. Never seen anything like it since.

[AugustusWhittle]

According to the Dail Mail (yes, I know I mustn't believe what I read in the press) Monarch are planning to provide wi-fi internet access for passengers at 35,000 feet. So presumably they're not worried about electronic devides being used to access the service. Is this feasible and how does it work given the coments in this thread?

Monarch to become first to offer wireless internet at 35,000 feet | Mail Online (http://www.dailymail.co.uk/money/article-2001822/Monarch-to-offer-wireless-internet-35-000-feet.html)

[rh200]

I think the problem is people don't really understand the problem deeply enough. There are far to many variables in the real world, and saying I went here with it switched on proves it's a crock.

Any one who has anything to do with RFI testing, arrays etc know's how pervasive RFI is, even on sheilded structures. Any single instance may not cause an incident, it could be any number of factors lining up in a row at a particular time that creates a problem.

We fly on aircraft that have been designed for extremely low statistical failure rates, going flying with your mobile on doesn't even approach being scientific method of proof.

[flydive1]

My questions are:

Do you really need to have your phone on during flight?
Are you really that important that you need to be available at any time?
Do you really need to find out if your phone causes interferences on your flight?

[Mechta]

Having done some EMC shielding validation/verification on a component, what was apparent is that shielding might be satisfactory when initially tested, but a few years down the line when the shield (in this case a coating of silver-loaded epoxy) or seal has suffered a bit of wear and tear, it may not work anything like as well. This is particularly so if the people removing and refitting the shields and seals do not appreciate how they work and the properties of the RF it is trying to keep in or out. Just because a type of aircraft is considered EMC compliant, doesn't mean that particular airframe is. I should think the costs of ensuring continued EMC compliance for all systems on an aircraft would be prohibitive.

A few years ago, when the Nintendo Gameboy DS became popular, I went with the family on a package holiday. When we got there, Mrs Mechta's granddaughter seemed to know a lot more about the other children at the hotel than I thought possible. When I quizzed her, it turned out she had been 'chatting' to the others via the DS's wireless network facility throughout the flight, so its not just phones and laptops that are the problem.

A lot of the problem with things like phones is that their owners think they are switched off when they are not. My own will burst into life with some long forgotten alarm from switched off state, so when I really need it off (as in an exam recently) I take the battery out. Even then there may still be a further battery inside to keep settings.

[chris weston]

Using mobiles in lessons is not permitted where I work. Of course the little s**s do - txt, Facebook, you name it.

So you confiscate it (and return it at the end of that session) when you do this the little s**s friends ring the confiscated phone.

I have a metal biscuit tin and a good solid croc to croc connector. The 'phone goes in, the tin gets earthed.

Works like a dream.

The tin fills up......

They eventually get to hear about about NEMP and the usefulness of Faraday cages after a satisfyingly frustrating time.

Could this idea be extended more widely? Patent free from me as a service to in-flight safety!

CW

[FlightPathOBN]

Study: In-flight cell phone use may cause serious problems | Seattle News, Weather, Sports, Breaking News | KOMO News | Local & Regional (http://www.komonews.com/news/local/123599754.html)

[Piper_Driver]

According to the Dail Mail (yes, I know I mustn't believe what I read in the press) Monarch are planning to provide wi-fi internet access for passengers at 35,000 feet. So presumably they're not worried about electronic devides being used to access the service. Is this feasible and how does it work given the coments in this thread?

Monarch to become first to offer wireless internet at 35,000 feet | Mail Online (http://www.dailymail.co.uk/money/article-2001822/Monarch-to-offer-wireless-internet-35-000-feet.html)

These services are only offered on aircraft that have been specially engineered and tested to handle RF in the WiFi band (2.4GHz).

[stepwilk]

I understand that we're talking about whether or not cellphones cause electromagnetic interference, but I'm surprised that nobody has mentioned that the real reason cellphones, iPods, Walkmans (if any still exist), video games and the like be turned off is not that anybody cares whether they interfere with anything, but because the cabin crew wants the SLF to be at least minimally paying attention and not have their ears blocked with buds during the phase of flight when it just might be most important to hear instsructions from F/As--takeoff to 10,000 feet. Above that, you can immerse yourself in the moronic pursuit of your choice.

It's why cabin crews would equally forbid two tin cans on a taut string, if there are any ex-Boy Scouts out there who remember how that worked...