AndyMan 7
Recommended Posts
QuoteQuoteI have a PCS phone, it is not required to turn it off.
I mentioned FCC rules.
Clearly the FAA also has rules. Break them at your own risk.
_Am
There is no FAA regulation. As far as I can find the FAA only "supports the FCC regulation."
But do you want to know what is really funny that I just found?
The seatback phones on airliners are regular cellular phones!! They use the existing cell sites on the ground in addition to special sites that point up.
http://www.aircell.com/
Edited to add some more informational reading
The FAA has rules restricting the use of PEDs on commercial airlines. Those rules, at 14 CFR 91.21, 121.306 and 135.144, prohibit the operation of a PED on an aircraft unless the airline has determined that the device will not cause interference with the navigation or communication system of the aircraft. The rule includes exceptions for portable voice recorders, hearing aids, heart pacemakers, and electric shavers to allow them to be used. The rules do not apply to private planes flying under visual flight rules (VFR).
Additionally, the FAA published Advisory Circular (AC) 91.21-1 in 1993 to help aircraft operators comply with FAA regulations. The AC recommended that the use of PEDs be prohibited during the takeoff and landing phases of flight below 10,000 feet. As justification, the FAA cites both the potential for electronic interference with aircraft systems and the potential for passengers to miss safety announcements.
The Federal Communications Commission (FCC) also has rules in this area. Its rule, at 47 CFR 22.925, prohibits the use of cell phones after the aircraft leaves the ground. This rule applies to all aircraft whether commercial or private or whether powered or simply a balloon. The FCC rule applies only to cell phones. It does not apply to other PEDs. Nor, according to a FCC engineer, does it apply to PCS phones such as the AT&T Wireless or the Sprint PCS.
From what it sounds like, Laptops and CD players actually cause more problems than cell phones do.
Source: http://www.house.gov/transportation/aviation/hearing/07-20-00/07-20-00memo.html
QuoteThe seatback phones on airliners are regular cellular phones!! They use the existing cell sites on the ground in addition to special sites that point up
DAMN, you stole my thunder. I was going to mention this but I wanted to see where this was going first. So do cell phones crash airplanes? If so, why do they have seat back phones? Is it just a conspiracy to get people to turn off their phones and use the ones on the seat back? Is it so that people's phones don't interrogate the countless number of towers it is communicating with at that altitude and while they rapidly move accross a wide geographical section? Is this all just BS to scare you into complying?
Frankly, I think it's BS. They don't know. They can't say for certain that all phones will cause interference so they err on the side of safety. I've flown many a time without turning my cell phone off and ya know what? My plane landed fine and the only noted anomoly was that my battery was drained. HMMMM , I wonder what casued that?
Edited to add: so where does this put the AFF students you have various makes and models of two way radios on them during flight? I have heard of a few cypess fires suspected to be caused by RF from transmiters. What of the instructor and student who both have radios on them and in the on position?
Of interest and why I suspect the general consensus is to turn them (cell phones)off is because of the chance of something going wrong. Case in point, using military electrical blasting caps for demolition charges using a remote firing system. All is fine and dandy, everything going according to plan. Medic makes a cell phone call to establish comms and BOOM, the charge goes off bigger than shit. Nothing could be recreated to cause the same effect but there is no doubt that as soon as the cell phone was used the explosives detonated. So, now whenever we use electical firing systems and remote firing devices the use of cell phones is prohibited. So in the end I think It's like sun spots. Some days it gets in the way and other times it doesn't.
"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING
billvon 3,111
.thumb.jpg.4bb795e2eaf21b8b300039a5e1ec7f92.jpg)
>The seatback phones on airliners are regular cellular phones!!
Huh? No they're not. It's a separate system using different frequencies and one central antenna _outside_ the aircraft.
Huh? No they're not. It's a separate system using different frequencies and one central antenna _outside_ the aircraft.
billvon 3,111
>The problem is that some times cell phones can impact systems or
>communications with their repeater and a lot of time they don't.
Same is true of laptop computers, CD players and GameBoys. I can understand your caution (why take chances?) but cellphones will only be prohibited until such time as the airline can make a few bucks on them. We've already done some early tests with cabin-based 'microcells' that essentially turn the aircraft into one cell of a cellphone system. A satellite or terrestrial LOS system then provides the backhaul.
>communications with their repeater and a lot of time they don't.
Same is true of laptop computers, CD players and GameBoys. I can understand your caution (why take chances?) but cellphones will only be prohibited until such time as the airline can make a few bucks on them. We've already done some early tests with cabin-based 'microcells' that essentially turn the aircraft into one cell of a cellphone system. A satellite or terrestrial LOS system then provides the backhaul.
Quote>The seatback phones on airliners are regular cellular phones!!
Huh? No they're not. It's a separate system using different frequencies and one central antenna _outside_ the aircraft.
They are chordless transmitting devices... Sure they may use a repeater, but that one antenna on the outside of the plane transmits/receives to/from standard and proprietary cell sites. So those frequencies must be the same.
Then the next question here is... what causes the navigational anomalies? RFI or EMI? My guess is the EMI since all the other devices interfere too. If that is the case.. regarless of frequency, the seatback phones could just as easily interfere.
QuoteIs it so that people's phones don't interrogate the countless number of towers it is communicating with at that altitude and while they rapidly move accross a wide geographical section? Is this all just BS to scare you into complying?
This is what I think the answer is... It is not really fair to be locking down a frequency across half a state because you hit all those towers at once.
But remember, this regulation is for analog phones. Digital PCS phones are different technology.
billvon 3,111
>They are chordless transmitting devices...
Well, they are all corded, and they all use one radio. On a typical business jet. there are nearly a dozen transmitters, from several VHF radios to TCAS to the transponder to satellite comm systems to HF radios. It's no problem as long as they are all designed and tested to not intefere with each other. Sometimes it takes a lot of effort to prevent such interference, depending on the frequencies involved.
>Sure they may use a repeater, but that one antenna on the outside of
>the plane transmits/receives to/from standard and proprietary cell sites.
>So those frequencies must be the same.
There is not a system out there that uses standard cell sites. They use a separate ground based system, with antennas and coverage patterns optimized for enroute aircraft. Note that cellphones in the US use frequencies from 800 to 1900 MHz. The GTE airphone system uses frequencies around 850-890 MHz; these are not frequencies ordinarily used by cellphones, although the frequencies are indeed close.
>Then the next question here is... what causes the navigational
>anomalies? RFI or EMI?
A bigger issue is conducted vs radiated, or inband vs out of band emissions. RFI is a type of EMI.
>My guess is the EMI since all the other devices interfere too. If that is the
> case.. regarless of frequency, the seatback phones could just as easily interfere.
They could, but they have been tested to ensure they do not. We have installed systems that use cellphone-like frequencies on aircraft, and to get the field approval we have to do test flights to ensure that the signals do not interfere with other aircraft equipment. There is little doubt that most cellphones would pass such tests, but they haven't been done very often.
Well, they are all corded, and they all use one radio. On a typical business jet. there are nearly a dozen transmitters, from several VHF radios to TCAS to the transponder to satellite comm systems to HF radios. It's no problem as long as they are all designed and tested to not intefere with each other. Sometimes it takes a lot of effort to prevent such interference, depending on the frequencies involved.
>Sure they may use a repeater, but that one antenna on the outside of
>the plane transmits/receives to/from standard and proprietary cell sites.
>So those frequencies must be the same.
There is not a system out there that uses standard cell sites. They use a separate ground based system, with antennas and coverage patterns optimized for enroute aircraft. Note that cellphones in the US use frequencies from 800 to 1900 MHz. The GTE airphone system uses frequencies around 850-890 MHz; these are not frequencies ordinarily used by cellphones, although the frequencies are indeed close.
>Then the next question here is... what causes the navigational
>anomalies? RFI or EMI?
A bigger issue is conducted vs radiated, or inband vs out of band emissions. RFI is a type of EMI.
>My guess is the EMI since all the other devices interfere too. If that is the
> case.. regarless of frequency, the seatback phones could just as easily interfere.
They could, but they have been tested to ensure they do not. We have installed systems that use cellphone-like frequencies on aircraft, and to get the field approval we have to do test flights to ensure that the signals do not interfere with other aircraft equipment. There is little doubt that most cellphones would pass such tests, but they haven't been done very often.
quade 4
Debating cell phone technology with billvon is a little like debating the speed of light with Michaelson.
quade -
The World's Most Boring Skydiver
The World's Most Boring Skydiver
fergs 0
OK, enough of the techo stuff!
I reckon I’ve got the best “how to use a cell phone in the sport” story – so the challenge is out …
10 years ago (remember those days – school kids didn’t own cell phones back then) I was doing my annual display jump into the Australia Day celebrations in Commonwealth Park in Canberra (that’s the country’s capital city).
That year we wanted to provide something “extra”. So between myself and a telecom technician friend we:
1. Developed a throat mike that was strapped onto my throat directly above my voice box. The mike had webbing above it too, so that wind noise was minimised.
2. Wired another cell phone into the TV / Radio station gear as well as the PA system in the Park..
On jump run I phoned the ground phone and basically made small talk about the scenery, what we were about to do, etc. Then on exit and in freefall I continued to chat – continuing on under canopy. We were a 4 way team (although this display was individual exits due low cloud). The plan always had me landing first, as I did on this jump. After landing I continued to give commentary on the last 3 jumpers as they landed.
All the time the radio and TV crews had my live commentary as a part of their shows. Plus it had been broadcast at the same time over the PA system.
Sure was a novel way of having live commentary for a display jump.
So let’s hear from others as to their use of a cell phone while skydiving.
Blue Skies,
fergbird
I reckon I’ve got the best “how to use a cell phone in the sport” story – so the challenge is out …
10 years ago (remember those days – school kids didn’t own cell phones back then) I was doing my annual display jump into the Australia Day celebrations in Commonwealth Park in Canberra (that’s the country’s capital city).
That year we wanted to provide something “extra”. So between myself and a telecom technician friend we:
1. Developed a throat mike that was strapped onto my throat directly above my voice box. The mike had webbing above it too, so that wind noise was minimised.
2. Wired another cell phone into the TV / Radio station gear as well as the PA system in the Park..
On jump run I phoned the ground phone and basically made small talk about the scenery, what we were about to do, etc. Then on exit and in freefall I continued to chat – continuing on under canopy. We were a 4 way team (although this display was individual exits due low cloud). The plan always had me landing first, as I did on this jump. After landing I continued to give commentary on the last 3 jumpers as they landed.
All the time the radio and TV crews had my live commentary as a part of their shows. Plus it had been broadcast at the same time over the PA system.
Sure was a novel way of having live commentary for a display jump.
So let’s hear from others as to their use of a cell phone while skydiving.
Blue Skies,
fergbird
QuoteThe seatback phones on airliners are regular cellular phones!! They use the existing cell sites on the ground in addition to special sites that point up.
Yes, and they are also hardwired into the aircraft's electrical system so they are not going to interfere with it!
Chris Schindler
www.diverdriver.com
ATP/D-19012
FB #4125
www.diverdriver.com
ATP/D-19012
FB #4125
Genn 0
Cell phones and CRW can be quite handy
Quote>The problem is that some times cell phones can impact systems or
>communications with their repeater and a lot of time they don't.
Same is true of laptop computers, CD players and GameBoys. I can understand your caution (why take chances?) but cellphones will only be prohibited until such time as the airline can make a few bucks on them. We've already done some early tests with cabin-based 'microcells' that essentially turn the aircraft into one cell of a cellphone system. A satellite or terrestrial LOS system then provides the backhaul.
Bill, I'm telling you as someone who flys airliners. I hear clicking in my headset when a cell phone (even the f'n precious PCS phone) is turned on in the back of the plane. It CAN interfere with me hearing what ATC just told me. That instruction just might be "Go around there is another plane on the runway" but if I didn't hear the call sign I might not know that was for me. Cell phones DO interfere with communication and we DO suspect them of causing certain anomalies onboard highly advanced electrical aircraft. Heck, we even had one guy get put onboard and his inplanted defibrilator started going off big time. We pulled him off with the paramedics. It went off a total of 12 times and you can hear it each time. The ramp agents said that was really weird because the same thing happened to him 2 weeks earlier when he tried to board. So don't tell me aircraft electrical systems can't be interfered with by an outside source. They emit a field and they can be influenced by a field.
Chris Schindler
www.diverdriver.com
ATP/D-19012
FB #4125
www.diverdriver.com
ATP/D-19012
FB #4125
billvon 3,111
>Cell phones DO interfere with communication and we DO suspect them of
> causing certain anomalies onboard highly advanced electrical aircraft.
No problem. You're the guy who flies the plane, I'm the guy who designs stuff that goes _in_ the plane. We both have different perspectives on how things work. Some cell phones can cause interference on some aircraft. Most cell phones don't cause interference on most aircraft. This can be proven; we've done some of the testing.
Mode-C transponders emit a much more powerful signal than any digital cellphone, and have, in some cases, been shown to interfere with other aircraft systems. That doesn't mean the answer is "never fly with the transponder turned on." The answer is "fix the transponder and the affected system." The same will happen with cellphones - again, once there's something in it for the airline.
> So don't tell me aircraft electrical systems can't be interfered with by an
>outside source. They emit a field and they can be influenced by a field!
Definitely. One of the many parts of certifying that a system is safe to fly with is showing that it generates a sufficiently low amount of EMI, and that the rest of the aircraft is sufficiently resistant to that EMI. Sometimes it's difficult. I designed one system that emitted several watts at 1620 MHz; it was within inches of a GPS antenna that receives signals at 1575 MHz. It took a lot of filtering to make sure the two would not interfere. Cellphones are farther from aircraft frequencies, emit at lower powers and are physically farther from other aircraft antennas, so they'll be a bit easier to work with.
> causing certain anomalies onboard highly advanced electrical aircraft.
No problem. You're the guy who flies the plane, I'm the guy who designs stuff that goes _in_ the plane. We both have different perspectives on how things work. Some cell phones can cause interference on some aircraft. Most cell phones don't cause interference on most aircraft. This can be proven; we've done some of the testing.
Mode-C transponders emit a much more powerful signal than any digital cellphone, and have, in some cases, been shown to interfere with other aircraft systems. That doesn't mean the answer is "never fly with the transponder turned on." The answer is "fix the transponder and the affected system." The same will happen with cellphones - again, once there's something in it for the airline.
> So don't tell me aircraft electrical systems can't be interfered with by an
>outside source. They emit a field and they can be influenced by a field!
Definitely. One of the many parts of certifying that a system is safe to fly with is showing that it generates a sufficiently low amount of EMI, and that the rest of the aircraft is sufficiently resistant to that EMI. Sometimes it's difficult. I designed one system that emitted several watts at 1620 MHz; it was within inches of a GPS antenna that receives signals at 1575 MHz. It took a lot of filtering to make sure the two would not interfere. Cellphones are farther from aircraft frequencies, emit at lower powers and are physically farther from other aircraft antennas, so they'll be a bit easier to work with.
QuoteWell, they are all corded,
That is incorrect, The two times I have pulled them off of the seatback there was NO cord. And, the Manufacturer's web site I previously linked to lists a cordless model.QuoteThere is not a system out there that uses standard cell sites.
I hear clicking in my headset when a cell phone (even the f'n precious PCS phone) is turned on in the back of the plane*** You always will. My PCS phone makes my earphones click whenever it checks in with the tower or right before it rings.Quote
That is incorrect again. The FCC exempted one company from the regulations, I followed a link from the FCC's website to that Manufacturer, AirCell, The Manufacturer's web site even states they use existing cell sites addition to the special ground system. In fact, existing cell sites were all they used until the completion of the upward facing towers network.
I hope the Manufacturers white papers are not total BS!
From diverdiver:
And to play the trump card....ya, I was saving this one
Regardless of the technical stuff, or what the FCC or FAA says. The Pilot of the plane and the flight crew ARE the law on any flight. Disobeying a request from them (i.e. turning off your cell phone when asked to) is a felony.
Regardless of the technical stuff, or what the FCC or FAA says. The Pilot of the plane and the flight crew ARE the law on any flight. Disobeying a request from them (i.e. turning off your cell phone when asked to) is a felony.
QuoteAnd to play the trump card....ya, I was saving this one
Regardless of the technical stuff, or what the FCC or FAA says. The Pilot of the plane and the flight crew ARE the law on any flight. Disobeying a request from them (i.e. turning off your cell phone when asked to) is a felony.
{Insert theme music here} BREAKING THE LAW, BREAKING THE LAW
"It's just skydiving..additional drama is not required"
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING
Some people dream about flying, I live my dream
SKYMONKEY PUBLISHING
Ok, I agree with all that Bill. But here is the other fact that the flying public has to accept. If your cell phone is on you might be on it too. When would a cell phone get a signal? Taxi, takeoff, and landing. What is the most critical phase of flying? Taxi, takeoff, and landing. I don't want any passenger on a cell phone in case of an emergency. And not all emergencies are obvious to passengers. I need them ready to hear crew member instructions. That's why the headphones that plug into the aircraft system are allowed to be used during these times. The PA system can break into the broadcast. Anything else it can not. Then there's the whole projectile issue. If you are talking on or listening to messages the phone could then be a projectile in a crash. Not a good thing. And jumpers should understand that issue well.
So, with all that I know, I have many reasons why people should turn their cell phone off while on airplanes. Even if they totally get rid of the interference that cell phones could ever cause I still don't want anyone using them.
So, with all that I know, I have many reasons why people should turn their cell phone off while on airplanes. Even if they totally get rid of the interference that cell phones could ever cause I still don't want anyone using them.
Chris Schindler
www.diverdriver.com
ATP/D-19012
FB #4125
www.diverdriver.com
ATP/D-19012
FB #4125
QuoteYou always will. My PCS phone makes my earphones click whenever it checks in with the tower or right before it rings.
And that's what I call communication interference. It must be turned off.
Chris Schindler
www.diverdriver.com
ATP/D-19012
FB #4125
www.diverdriver.com
ATP/D-19012
FB #4125
riddler 0
QuoteThe Pilot of the plane and the flight crew ARE the law on any flight. Disobeying a request from them (i.e. turning off your cell phone when asked to) is a felony.
I really wish more jumpers understood this.
So, regarding cell phone on jump planes, I hear this from BillVon:
Quotethere was never a similar regulation passed concerning PCS phones.
So it's not illegal to have a PCS phone *on* as long as it's not used to make a call?
And this from Chris:
QuoteI hear clicking in my headset when a cell phone (even the f'n precious PCS phone) is turned on in the back of the plane.
And this from Bill:
QuoteOn most modern aircraft, nothing will be affected.
I don't think I've sever seen a modern skydiving plane
But most of them (in my experience) are VFR, not IFR.
Sounds like it's just plain safer to make sure all cell phones (GPRS included) are turned off in the plane. I can get my DA reports on the ground.
billvon 3,111
>The two times I have pulled them off of the seatback there was NO cord.
Sorry, I was talking about the GTE airphone system. There are systems that use cordless links between the handset and base, then another link from the aircraft to the ground.
>The FCC exempted one company from the regulations . . .
To use most frequencies you need to get FCC approval; approval for cellphone operation does not extend to approval to operate the same system at higher power levels on aircraft. You can definitely _get_ that approval if you work at it, and you can get approval for using that new system with another company's ground based cellphone system. However, that's a far cry from being similar to using a cellphone in flight.
>In fact, existing cell sites were all they used until the completion of
>the upward facing towers network.
They use Iridium, a satellite communications system, to fill in many of their holes in coverage. I'd be interested to see what their agreement with ground-based non-aviation cells covered.
Sorry, I was talking about the GTE airphone system. There are systems that use cordless links between the handset and base, then another link from the aircraft to the ground.
>The FCC exempted one company from the regulations . . .
To use most frequencies you need to get FCC approval; approval for cellphone operation does not extend to approval to operate the same system at higher power levels on aircraft. You can definitely _get_ that approval if you work at it, and you can get approval for using that new system with another company's ground based cellphone system. However, that's a far cry from being similar to using a cellphone in flight.
>In fact, existing cell sites were all they used until the completion of
>the upward facing towers network.
They use Iridium, a satellite communications system, to fill in many of their holes in coverage. I'd be interested to see what their agreement with ground-based non-aviation cells covered.
billvon 3,111
>The PA system can break into the broadcast.
And it could at least disable any microcell based cellular phone communication system on an aircraft, which would at the very least cause the calls on the system to drop.
>Then there's the whole projectile issue.
I don't see any difference between cellphones and, say, books in that regard. A great many people read books during takeoff and landing - and books are orders of magnitude heavier than phones. In any case, a directive to 'stow everything' should apply to everything, books and cellphones included.
>I have many reasons why people should turn their cell phone off while on airplanes.
>Even if they totally get rid of the interference that cell phones could ever cause
>I still don't want anyone using them.
Right now, I agree - there aren't any systems that I know of that allow usage of your cellphone while on board. But even today, some Airbus A340's and Boeing 767's have 802.11b wireless networks on board, with all the same problems of any other wireless network (including cellular networks.) It won't be long until cells that allow usage of cellphones are installed on aircraft. We have one such system; the GSM folks (which is worse in terms of interference) have them ready to go as well, and are just awaiting approvals to put them on aircraft.
And it could at least disable any microcell based cellular phone communication system on an aircraft, which would at the very least cause the calls on the system to drop.
>Then there's the whole projectile issue.
I don't see any difference between cellphones and, say, books in that regard. A great many people read books during takeoff and landing - and books are orders of magnitude heavier than phones. In any case, a directive to 'stow everything' should apply to everything, books and cellphones included.
>I have many reasons why people should turn their cell phone off while on airplanes.
>Even if they totally get rid of the interference that cell phones could ever cause
>I still don't want anyone using them.
Right now, I agree - there aren't any systems that I know of that allow usage of your cellphone while on board. But even today, some Airbus A340's and Boeing 767's have 802.11b wireless networks on board, with all the same problems of any other wireless network (including cellular networks.) It won't be long until cells that allow usage of cellphones are installed on aircraft. We have one such system; the GSM folks (which is worse in terms of interference) have them ready to go as well, and are just awaiting approvals to put them on aircraft.
To billvon:
From what it said on their website they have usage agreements with 20 something major cellular carriers. I would assume that it is probably the same type of roaming agreement that they all use.
To riddler:
So Have fun all! I'm off to the DZ See ya Monday morning--if weather permits.
QuoteThey use Iridium, a satellite communications system, to fill in many of their holes in coverage. I'd be interested to see what their agreement with ground-based non-aviation cells covered.
From what it said on their website they have usage agreements with 20 something major cellular carriers. I would assume that it is probably the same type of roaming agreement that they all use.
To riddler:
Exactly! and why not discuss it with your jump pilot? That's what I am going to do this weekend.QuoteSounds like it's just plain safer to make sure all cell phones (GPRS included) are turned off in the plane. I can get my DA reports on the ground.
So Have fun all! I'm off to the DZ See ya Monday morning--if weather permits.
I mentioned FCC rules.
Clearly the FAA also has rules. Break them at your own risk.
_Am
You put the fun in "funnel" - craichead.
Share this post
Link to post
Share on other sites