Venezuela747 From United States of America, joined Jan 2004, 1451 posts, RR: 4
Reply 1, posted (9 years 7 months 3 days 5 hours ago) and read 7245 times:
I don't think it matters....I couldn't get any service at 30,000 ft. I was tryin to stay updated on MarchMadness and when Uconn almost lost to Bradley, and I was also flyin ATL-COS. I started gettin the updates as we were approaching COS.
It's not like the FA could tell since it was in silent and they were all txt messages.
LTBEWR From United States of America, joined Jan 2004, 13767 posts, RR: 17
Reply 2, posted (9 years 7 months 2 days 22 hours ago) and read 7231 times:
While there is only minor evidence or proof where personal cell phones will interfere with aircraft radio and electronic systems, one issue is that with so many different cell phones, frequencies used, etc., it may be impossible to give a blanket ok. As a result, to be on the safe side, they are banned within the a/c at all times.
TLG From United States of America, joined Jul 2005, 395 posts, RR: 0
Reply 3, posted (9 years 7 months 2 days 20 hours ago) and read 7224 times:
I've heard (second hand, so I can't verify the validity) that it's not really a danger, but the cell phone companies want them banned because with the high speed they jump towers so fast that they can't reliably be tracked for billing. It does seem to me that if there really was a danger of confusing aircraft equipment that you wouldn't even be allowed to have them on the plane.
MechEngineer From Germany, joined Jun 2006, 46 posts, RR: 0
Reply 9, posted (9 years 7 months 2 days 10 hours ago) and read 7197 times:
I can't remember the reference, but there was an investigation published some months ago showing that, while individual cellphones are no danger to the aircraft, the electromagnetic noise generated by several dozen of them all trying to get a connection inside a metal fuselage at the same time IS a danger to aircraft systems because of interference and sub-frequencies.
DYflyer From Norway, joined May 2006, 676 posts, RR: 13
Reply 13, posted (9 years 7 months 2 days 5 hours ago) and read 7178 times:
It is safe. Both the Swedish and Norwegian government have OK'd it after intensive testing, so i expect to see cells on SK flights soon . I also believe the French have tested this and concluded it is safe.
Life is like a book. If you don't travel, you only read one page.
MattRB From Canada, joined Apr 2005, 1624 posts, RR: 8
Reply 14, posted (9 years 7 months 2 days 5 hours ago) and read 7175 times:
Quoting Dimoko (Reply 11): and i love turning the phone back on and having a few messages, it makes me feel special!
Unless it's from your airline advising you that your connecting flight has been cancelled
EM interference aside, I don't want to see cellphones allowed in flight because I like as quiet as a flight as I can get. I can see air rage going on the rise if the yappers are allowed to flap their gums at cruise altitudes on their phones..
Aviation is proof that given, the will, we have the capacity to achieve the impossible.
Lobster From Germany, joined Oct 2008, 49 posts, RR: 0
Reply 16, posted (9 years 7 months 1 day 18 hours ago) and read 7150 times:
Whether cell phones are a danger or not, I hope they stay banned. It's the only place on earth that you can go (mostly) and not hear a damn cell phone ringing!! There is no where sacred anymore and people ringtones are SO annoying.
DeltaGator From United States of America, joined Sep 2005, 6341 posts, RR: 12
Reply 17, posted (9 years 7 months 1 day 7 hours ago) and read 7130 times:
Quoting 2H4 (Reply 15): Cellphones most certainly ARE a danger to the safety of the flight.
Proof? Source? Oh wait, just your opinion. Never mind.
If airlines are using instruments that coincide with the licensed and discrete wavelengths used by cell phones then that is an airline begging for a disaster.
I'm all for keeping cell phones banned from in flight use since I could care less about Aunt Marge's kid in prison, Uncle Guido's oozing cyst, or anyone else's conversation...including mine. Flight time is a few hours where I can close my eyes and escape the crap on the ground.
"If you can't delight in the misery of others then you don't deserve to be a college football fan."
Some Anecdotes and Discussion
Jim Irving is a colleague who flies B737 aircraft for a major US carrier. He has an anecdote:
One day departing Portland Oregon we noted that the FMC [Flight Management Computer] Map display showed a disagreement with the "raw data" VOR position. Our training is such that we would normally immediately switch over to "raw data" and assume the FMC was in error.
We would have done that except that it was a beautifully clear day and I looked out the window and was able to determine that the FMC seemed to be right on. I called back to the cabin and asked the flight attendants to check for someone using a cell phone or computer. A few minutes later they called back to say that a man had been using his cell phone and it was now off. Strangely (?) our VOR and FMC map now agreed.
Later in the flight the flight attendants called back and said that they had caught the man using his cell phone again but this time we had not noticed any problems, perhaps because we were in cruise far from the ground and not paying as much attention.
Another pilot's account:
In our company we recently had a Localizer deviation (out of tolerances) on a B737-200 related to a GSM (mobile phone) being operated by a passenger (who was disregarding our company regulations). When requested by the cabin crew to switch off his GSM, localizer indications became normal. Is this scientific proof? Certainly not, but good enough for me as a captain to insist that all the electronic toys, computers, mobile phones, etc., are OFF during critical phases of flight. [...]
I had fuel indications on the FMC going crazy on board the B737, that returned to normal when all electronic stuff in the back was switched off. I suspect a "Gameboy" electronic game device to have interfered, but this is no more than a guess. No, I did not ask to switch the toy back on again and investigate more in depth as I was responsible for the safety of 140 passengers and this would have been extremely irresponsible! This is not a situation in which to do such testing! This [ever-present responsibility accounts for why] there is no "proof" of the relationship.
I also recall experiencing *impossible* mode annunciations on the FMA (flight mode annunciator) on B737. Having both the autothrottle AND the pitch channel of the autopilot trying to maintain speed (both in MCP SPD mode) for example, not programmed by the pilot (you cannot program that). After an expensive in-depth troubleshooting session by our maintenance department, the incompatible mode annunciations were traced to a ... faulty cockpit window heat wiring. This caused electronic interference with the auto flight system.
Here are some more incidents:
June 07, 1997. B737-300: *Verify position* was indicated on the CDU. Both IRS and radio position were correct, the FMC position was not. The difference rapidly increased to 8 nautical miles. After switching a GSM in the cabin from STBY to OFF, the FMC updated normally. FMC was correct for the remainder of the flight and on the return flight.
April 30, 1997. B737-400: During level cruise, the AP pitched up and down with ROC/ROD of 400 fpm indicated. Other AP was selected: no change. Cabin was checked for PC's and other electronic devices: nothing was found. Requested passengers to verify that their mobile phone (GSM) was switched OFF. Soon
after this request all pitch oscillations stopped.
[There was one incident reported with a] B737-200. During approach to MAN (Manchester International, UK), the LOC for landing runway 24 oscillated and centered with the aircraft not on track (but offset), confirmed visually. Ground equipment was monitored and working normally. When a GSM in the cabin was switched off, all indications became correct.
More examples, taken directly from NASA's ASRS:
In October of 1998, a Boeing 757, flying from Seattle to Covington/Cincinnati, experienced loss of all three of its autopilot systems. Flight attendants checked for a passenger using a portable electronic device and discovered a man wearing headphones, which were part of a hearing aid. The passenger was allowed to continue using the device, but was moved forward several rows. The autopilot system then regained full operational capabilities and was later checked by maintenance, with no problems being found.
In March of 1997, a Cessna 340/A pilot experienced erroneous readings when attempting to determine his location because of a passenger using a cellular phone. After the passenger turned off the phone, the pilot was able to locate his position and continue on with no problems.
In January of 1997, a regional jet was flying from Salt Lake City to Eugene. The flight crew received three separate warning messages stating that there were disagreements between the captain’s and the first officer’s instruments. The three warnings were for discrepancies in heading, airspeed, and altitude indicators. After flight attendants checked the cabin for passengers using portable electronic devices and had the devices turned off, all problems ceased.
In August 1995, an aircraft making its approach to George Bush Intercontinental Airport in Houston was advised that it was 4 miles off course. Because the course director indicators had been scalloping left and right of center, the captain ordered the flight attendant to check the cabin for any passengers using a portable electronic device. Within 15 seconds, problems with the course director indicators disappeared. The captain later learned that a passenger had been using a portable computer.
In May of 1995, the electric compass indicators of the first officer of a Boeing 737 gave erratic readings. After a sweep of the cabin was made for portable electronic devices, which resulted in flight attendants asking a passenger to turn off a compact disc player, the first officer’s instruments returned to normal working order.
Shortly after takeoff from Baltimore, in April 1994, an aircraft was advised by ground control that it was 10 miles off course, though the plane’s instruments indicated nothing abnormal. It was found that a passenger in first class was using a portable computer. After the computer was turned off, navigation instruments returned to normal.
In February 1994, a turboprop aircraft flying government officials from Lake Havasu, AZ to Yuma, AZ experienced trouble with its navigational radios. Ground control showed that the airplane was off course and gave corrections. However, the plane’s navigation system had been checked earlier in the month and was said to have zero error. After the flight, the pilot learned that at least one passenger was using a cellular phone while the plane was in the air.
In August 1992, a turbojet aircraft was notified three times, by two different control towers, that it looked to be off course. All instruments in the cockpit were showing the plane’s position to be correct. Flight attendants searched for portable electronic devices and found a tape machine and a hand-held video game unit in use. The devices were turned off and there were no other navigational discrepancies during the flight.
In September of 1990, a plane travelling from Boston to Youngstown/Warren, OH was advised it was off course and was issued a new heading. The plane’s navigational instruments showed it to be on course. After checking the cabin for portable electronic devices, the lead flight attendant informed the captain that 23 passengers were using AM/FM cassette players and one passenger was using a personal computer. The passengers were asked to turn off the devices and the flight proceeded without further incident.
John Dimtroff is an electrical engineer on the Transport Standards Staff of the FAA Transport Aircraft Certification Directorate in Seattle. He is also a member of the Joint Airworthiness Authority/Federal Aviation Administration Electromagnetic Effects Harmonization Working Group. He has been a Federal Communications Commission investigator and inspector, a Boeing RF design engineer and a US Air Force Radar Specialist.
Dimtroff reports some incidents first-hand:
...my experience with the FCC has taught me [to wonder] how many [PED] devices transmit with a clean, zero-spur signal, especially after being dropped, banged, klunked, fondled and sat upon. [In] my former FCC investigative days, [I saw] a number of devices (computers, stereos, TV's, etc., etc.) which purportedly met FCC Part 15 requirements as indicated by their label, [but] were either bogus marked, illegally imported or were just outside the manufacturing quality bell curve. [My personal view is] that every carry-on electronic device is suspect -- until it has been individually tested, which, of course, is impossible.
[My experience suggests to me that] it is nearly impossible to predict/replicate an EMI event on an aircraft when the event involves a portable carry-on device (PED). Location, orientation, power output, modulation, inconjunction with ALL the other PED's/electronics/electrics/avionics active at that time all play a role in the EMI event. And we must not exclude the terrestial based emitters (radars, etc). ...
Finally, the pilot in command is directly responsible for the safety of those on board the aircraft. As André Berger has remarked, this responsibility includes avoiding all potential safety degradations, no matter how minimal. Thus, if EMI from a passenger PED is suspected, the only appropriate recourse, according to this legislative responsibility, is for the pilot to require the device immediately be turned off completely. This precludes any kind of correlation testing, benign or otherwise.
And finally, DeltaGator, here's a source for you:
In response to a FAA request, RTCA Special Committee 177 was formed in 1992 to investigate and determine the causes of the potential interference to installed aircraft electrical and electronic systems from portable electronic devices (PED) carried aboard aircraft by passengers.
Those findings indicated that the probability of interference to installed aircraft systems from PED, singly or in multiples, is extremely slight. However, the slight possibility of interference to aircraft navigation and information systems during critical phases of flight, e.g., takeoff and landing, should be viewed as potentially hazardous and an unacceptable risk for aircraft involved in passenger carrying operations. Therefore, the committee recommends that the use of PEDs be restricted during certain critical phases of flight.
IAirAllie From , joined Dec 1969, posts, RR:
Reply 19, posted (9 years 7 months 1 day 1 hour ago) and read 7113 times:
Cell phones are a danger. On it's own a single cell phone functioning normaly is not much of a danger. Take 200 cell phones some of which have been dropped or dammaged so they aren't functioning within normal parameters and you could have a problem. Any crash is preceeded by a chain of errors, remove even one link and the accident could be avoided. Banning cellphones is a way to eliminate one of the links in that chain of error.
DeltaGator From United States of America, joined Sep 2005, 6341 posts, RR: 12
Reply 20, posted (9 years 7 months 20 hours ago) and read 7105 times:
Quoting 2H4 (Reply 18): In response to a FAA request, RTCA Special Committee 177 was formed in 1992
1992? Anything more recent with digital cell phones being researched instead of the old analog ones? I stand by the statement that if an airline uses instruments that function in the same frequencies of registered and licensed cell phone bands then they are begging for a disaster.
Believe me that I don't want them in the air but what about all the private pilots that use them with no crashes attributed to them? There must be something to it.
"If you can't delight in the misery of others then you don't deserve to be a college football fan."
2H4 From United States of America, joined Oct 2004, 8957 posts, RR: 58
Reply 21, posted (9 years 7 months 20 hours ago) and read 7104 times:
Quoting DeltaGator (Reply 20): I stand by the statement that if an airline uses instruments that function in the same frequencies of registered and licensed cell phone bands then they are begging for a disaster.
Well, then the entire global airline industry is, by your criteria, "begging for a disaster"...
Quoting DeltaGator (Reply 20): but what about all the private pilots that use them with no crashes attributed to them?
If you examine the ASRS reports posted above, you'll see that general aviation is affected by PEDs, as well. Regardless, though, your logic.....that "if it hasn't happened yet, it must not be a problem"....is very misguided and dangerous from a safety perspective, in that it's entirely reactive to accidents and incidents. The key is to predict and anticipate problems, and then take measures to be proactive, thereby minimizing risk. Waiting for the problems to surface on their own would result in many, many unnecessary deaths.
RwSEA From Netherlands, joined Jan 2005, 3242 posts, RR: 2
Reply 22, posted (9 years 7 months 19 hours ago) and read 7100 times:
Quoting TLG (Reply 3): I've heard (second hand, so I can't verify the validity) that it's not really a danger, but the cell phone companies want them banned because with the high speed they jump towers so fast that they can't reliably be tracked for billing. It does seem to me that if there really was a danger of confusing aircraft equipment that you wouldn't even be allowed to have them on the plane.
Bingo! That's it. It messes up all of the cell towers and the companies can't accurately track the calls. If phones were that dangerous, they wouldn't be allowed on board. That said, I don't want their use allowed because I enjoy not listening to other people's calls.