air traffic

[MUTNAV]

I, also, have been flying for the airlines for nearly 20 years. I have most definitely had cell phones interfere with VHF comms, though it depends on the aircraft.

During my time at the regional, I had multiple occasions of heavy ticking/buzzing in my headset from phones...on one occasion I was holding short of the inboard runway at Newark and could not hear any ATC clearances to cross 22R because of everyone turning on their phones at the same time after landing on 22L. Have also had strong buzzing inside the marker on an ILS when someones phone who was left on started to affiliate with the system as we descended on the glide...if it was buzzing that loud in my ear it was likely also buzzing that loud on my ILS receiver...not cool when the weather is down to mins. This was all on Embrare aircraft.

Now, at mainline and flying the Beautiful Bus, I have never had a problem...YMMV

Concur with your ideas, VHF comms is the least of the concerns to me, ILS much more so....

Keep in mind that even strong MAGNETS have to be specially packed to ship on on airplane.

Thanks
Joel

 

[MILCOMM]

I, also, have been flying for the airlines for nearly 20 years. I have most definitely had cell phones interfere with VHF comms, though it depends on the aircraft.

During my time at the regional, I had multiple occasions of heavy ticking/buzzing in my headset from phones...on one occasion I was holding short of the inboard runway at Newark and could not hear any ATC clearances to cross 22R because of everyone turning on their phones at the same time after landing on 22L. Have also had strong buzzing inside the marker on an ILS when someones phone who was left on started to affiliate with the system as we descended on the glide...if it was buzzing that loud in my ear it was likely also buzzing that loud on my ILS receiver...not cool when the weather is down to mins. This was all on Embrare aircraft.

Now, at mainline and flying the Beautiful Bus, I have never had a problem...YMMV

Thank you for making my point!

 

[KevinC]

I, also, have been flying for the airlines for nearly 20 years. I have most definitely had cell phones interfere with VHF comms, though it depends on the aircraft.

During my time at the regional, I had multiple occasions of heavy ticking/buzzing in my headset from phones...on one occasion I was holding short of the inboard runway at Newark and could not hear any ATC clearances to cross 22R because of everyone turning on their phones at the same time after landing on 22L. Have also had strong buzzing inside the marker on an ILS when someones phone who was left on started to affiliate with the system as we descended on the glide...if it was buzzing that loud in my ear it was likely also buzzing that loud on my ILS receiver...not cool when the weather is down to mins. This was all on Embrare aircraft.

Now, at mainline and flying the Beautiful Bus, I have never had a problem...YMMV

How do you know this was caused by cellphones?

 

[MILCOMM]

How do you know this was caused by cellphones?

Ah hello....the interference only happens when there is a cell phone on board.
Produce of elimination?

 

[KevinC]

Ah hello....the interference only happens when there is a cell phone on board.
Produce of elimination?

That’s nice, but I’d like the person I asked to answer.

 

[immelmen]

How do you know this was caused by cellphones?

The same way you can identify a Radio Teletype signal, a trunking control channel or your wife's voice...because of how it sounds. Cell phones have a very specific cadence when they are doing their thing. hold one up next to a speaker with the volume cranked up and turn it on: Bupadip bupadip bupadip bupadip bupubuzzzzzzzzzzzzzzzzzzzzzzz. Say versus the ACARS system which has a very different, higher pitched, sharper and more ear piercing screech than a phone.

FWIW, the Embrare aircraft that are susceptible to cell phone interference also get bleed through from their own ACARS transmissions (obviously a poorly designed comms system/shield). I also remember instances back then of the ACARS acknowledging an inbound message and the bleed through blocking an ATC call....unlike cell phones ACARS can/will screech at any altitude, however the ACARS bursts are much shorter than the cell phone.

 

[KevinC]

The same way you can identify a Radio Teletype signal, a trunking control channel or your wife's voice...because of how it sounds. Cell phones have a very specific cadence when they are doing their thing. hold one up next to a speaker with the volume cranked up and turn it on: Bupadip bupadip bupadip bupadip bupubuzzzzzzzzzzzzzzzzzzzzzzz. Say versus the ACARS system which has a very different, higher pitched, sharper and more ear piercing screech than a phone.

FWIW, the Embrare aircraft that are susceptible to cell phone interference also get bleed through from their own ACARS transmissions (obviously a poorly designed comms system/shield). I also remember instances back then of the ACARS acknowledging an inbound message and the bleed through blocking an ATC call....unlike cell phones ACARS can/will screech at any altitude, however the ACARS bursts are much shorter than the cell phone.

So it’s a crappy design all around and not specific to cell phones, especially if they receive interference from their own onboard devices.

 

[alcahuete]

99.999% of the time, the interference is due to poor shielding in the pilot headsets, and that's why pilots can sometimes hear the "cell phone sound." Turn the speakers on and take your headset off, and you'll see that it immediately goes away. Is that interference? Sure. But it isn't going to bring the plane down. It is extremely rare these days (basically non-existent) for electronic devices to cause interference to the avionics themselves.

 

[immelmen]

So it’s a crappy design all around and not specific to cell phones, especially if they receive interference from their own onboard devices.

yup. my experience with it was specific to Embrare. Have never heard it since on the Airbus or Boeing. never flew the CRJs so not sure about them.

 

[immelmen]

99.999% of the time, the interference is due to poor shielding in the pilot headsets, and that's why pilots can sometimes hear the "cell phone sound." Turn the speakers on and take your headset off, and you'll see that it immediately goes away. Is that interference? Sure. But it isn't going to bring the plane down. It is extremely rare these days (basically non-existent) for electronic devices to cause interference to the avionics themselves.

That is not the case in in this instance. Crews commonly take the headseats off above 18000 ft and commonly taxied with them off in the Embrare. All of the interference I described above is in the aircraft's system and is audible through the speaker...it does not go away and is a well known and documented issue. There were many many FAA ASAP reports filed by pilots detailing the problem and the Airline put out internal communications stating they were working with Embrare in an attempt to resolve the issue.

Edit to add: the issue is not causing interference to the avionics themselves, I dont see why that would even be a consideration. It is very possible, however, to distort, disrupt or corrupt the reception by the aircraft of the signal transmitted by an instrument landing system...the FAA establishes ILS critical areas for that very reason....Further, as I posted earlier, I have personally experienced cellphone interference dirrectly affecting saftey of flight when I could not hear a controller issuing runway crossing instructions to my aircraft. Runway incursion has gotten people killed more than once before.

 

[alcahuete]

That is not the case in in this instance. Crews commonly take the headseats off above 18000 ft and commonly taxied with them off in the Embrare. All of the interference I described above is in the aircraft's system and is audible through the speaker...it does not go away and is a well known and documented issue. There were many many FAA ASAP reports filed by pilots detailing the problem and the Airline put out internal communications stating they were working with Embrare in an attempt to resolve the issue.

Any airworthiness directives on any of that? If it is such a known safety issue in Embraer aircraft, there should be an AD calling for repairs.

the FAA establishes ILS critical areas for that very reason....

Not even close. ILS critical areas are established ON THE GROUND so that vehicles, aircraft, etc. do not interfere with or attenuate the ILS signal. It has absolutely nothing to do with interference from onboard electronic devices.

 

[FedFyrGuy]

Interesting reading (Boeing):

AERO Interference from Electronic Devices

AERO is a quarterly magazine published by Boeing Commercial Airplane Group providing operators of Boeing and Douglas commercial airplane products with supplemental technical information to promote continuous safety and efficiency in fleet operations.

www.boeing.com

 

[KK4JUG]

Remember when hospitals banned cell phones? About the same time that smart phones were born, the proscription began to disappear. Does that also apply here?

 

[chrismol1]

Interesting reading (Boeing):

AERO Interference from Electronic Devices

AERO is a quarterly magazine published by Boeing Commercial Airplane Group providing operators of Boeing and Douglas commercial airplane products with supplemental technical information to promote continuous safety and efficiency in fleet operations.

www.boeing.com

Yea, I remember electronics back then put out a lot of crap shielding wasn't as great
by the way, what was the power output of cell phones back in the 90s?

 

[nd5y]

what was the power output of cell phones back in the 90s?

The analog AMPS standard had 8 power levels from 8 dBm to 36 dBm (6 mW to 4.0 W) in 4 dB steps with a tolerance of +2/-4 dB. The first three power levels were all the same on hand helds (28 dBm or 630 mW) but most portable (bag phones) and mobiles had up to 1.6 or 4.0 W as the highest power. When TDMA-136 digital came out there were three more low power levels added that went down to -4 dBm (0.4 mW)

Now it depends on the type of phone, frequency band and technology used.
You can look up the FCC ID of your phone and see what the max power output is.

 

[INLANDNEWS]

We use VHF radios in both Helicopters and Airplanes for off-road race communications. Several pilots use their IPADS for navigation. Some even have a bluetooth set-up that allows them to make cell phone calls through their headsets. Usually only works when you are below 3,000ft though.

 

[RichardKramer]

Ah hello....the interference only happens when there is a cell phone on board.
Produce of elimination?

I just made some cell phone calls while searching the 108 - 137MHz band in the AM mode while having the cell phone right up against my BCD396 scanner w/rubber duck - can't figure out why I'm not getting any rfi from it - only high powered VHF pagers. Gee, maybe the cell phone towers could be the culprit, if at all, with their much higer power levels???

 

[G7RUX]

The same way you can identify a Radio Teletype signal, a trunking control channel or your wife's voice...because of how it sounds. Cell phones have a very specific cadence when they are doing their thing. hold one up next to a speaker with the volume cranked up and turn it on: Bupadip bupadip bupadip bupadip bupubuzzzzzzzzzzzzzzzzzzzzzzz. Say versus the ACARS system which has a very different, higher pitched, sharper and more ear piercing screech than a phone.

FWIW, the Embrare aircraft that are susceptible to cell phone interference also get bleed through from their own ACARS transmissions (obviously a poorly designed comms system/shield). I also remember instances back then of the ACARS acknowledging an inbound message and the bleed through blocking an ATC call....unlike cell phones ACARS can/will screech at any altitude, however the ACARS bursts are much shorter than the cell phone.

GSM phones do, CDMA/3G/4G/5G do not...