"DaveC" wrote in message
al.net...
Cell phone usage is restricted on all domestic commercial flights by the
FAA,
so the flight attendant keeps telling me.

The regulation against using electronic devices that have not been
determined by the operator to be harmless pre-dates the invention of
cellular phones. The text of the regulation is:

§ 121.306 Portable electronic devices.
(a) Except as provided in paragraph (b) of this section, no person may
operate, nor may any operator or pilot in command of an aircraft allow the
operation of, any portable electronic device on any U.S.-registered civil
aircraft operating under this part.

(b) Paragraph (a) of this section does not apply to-

(1) Portable voice recorders;

(2) Hearing aids;

(3) Heart pacemakers;

(4) Electric shavers; or

(5) Any other portable electronic device that the part 119 certificate
holder has determined will not cause interference with the navigation or
communication system of the aircraft on which it is to be used.

(c) The determination required by paragraph (b)(5) of this section shall be
made by that part 119 certificate holder operating the particular device to
be used.


The FCC prohibits using cellular phones on aircraft, but that applies only
to cellular phones, few of which exist any more. Most modern 'cellular'
phones are in fact PCS phones, which are not subject to that regulation.
This ban was created when the regulations for cellular phones were first
written and was not included in the regulations for PCS phones.

Anyway, cellular phones are specifically banned by the FCC and few flight
attendants are probably willing or able to verify whether a particular phone
is covered by the regulation or not, while all portable electronic devices
are banned by the FAA unless the air carrier has determined that they will
not be harmful. Few air carriers are probably willing to test every type and
model of electronic device for radio interference, but most of them have no
problem with pocket calculators, laptop computers, and the like, even though
a laptop computer or PDA with Bluetooth or WiFi would seem to be a potential
problem.

DaveC wrote:
Cell phone usage is restricted on all domestic commercial flights by the FAA,
so the flight attendant keeps telling me.

Nope. The FAA rules have not changed on this, nor have the FCC ones.
You can't use Advanced Mobile Phone Service (i.e., traditional cellular)
airborne. That is an FCC rule.

The FAA rule is just that the airline (i.e., the operator) must
determine when electronic devices are safe to use. The only thing that
has really changed is the "conventional wisdom" on the FAA's part got a
little tighter after some supposed interference issues (primarily blamed
on laptops) a few years back.

Is cell phone usage also restricted on private jets, etc. for similar
reasons?

Yes, all airborne use is prohibited. On cell phones permanently
installed on private jets, there has to be a warning label attached to
prohibit it's use in the air. (FCC rule).

So my question... what is the technical reason for restriction of cell phone
us on commercial flights? Is this reason valid, technically? Or is it simply
an excuse to force anyone who needs to make a call to use the airline's
on-board phones (and pay their outrageous rates)?

Forcing you to use the Airphones is the least of the FAA's or the FCC's
concern.

The real reason is that the cellular phone industry does not want you
to. Their bread and butter is the ground based caller, and their
systems are not designed to work with callers that have some altitude on
the system (there are techncial deficiencies in this that I won't go
into unless you really want to know). As a matter of fact, the cellular
industry fought a company who wanted to share the spectrum
tooth-and-nail over airborne use.

Oddly, this prohibition is NOT written into the rules for the newer
wireless services (PCS, NEXTEL, etc...) that operate outside the AMPS
(800MHz) band. However, most of the carriers with these services still
discourate airborne use.

I noticed on the evening news the other night that someone is trying to get
a modular mobile "cell tower" approved that would be installed in commercial
aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)

I don't have to like Bush and Cheney (Or Kerry, for that matter) to love
America

"Ron Natalie" wrote in message
m...
DaveC wrote:
Cell phone usage is restricted on all domestic commercial flights by the
FAA,
so the flight attendant keeps telling me.

Nope. The FAA rules have not changed on this, nor have the FCC ones.
You can't use Advanced Mobile Phone Service (i.e., traditional cellular)
airborne. That is an FCC rule.

The FAA rule is just that the airline (i.e., the operator) must
determine when electronic devices are safe to use. The only thing that
has really changed is the "conventional wisdom" on the FAA's part got a
little tighter after some supposed interference issues (primarily blamed
on laptops) a few years back.

Is cell phone usage also restricted on private jets, etc. for similar
reasons?

Yes, all airborne use is prohibited. On cell phones permanently
installed on private jets, there has to be a warning label attached to
prohibit it's use in the air. (FCC rule).

So my question... what is the technical reason for restriction of cell
phone
us on commercial flights? Is this reason valid, technically? Or is it
simply
an excuse to force anyone who needs to make a call to use the airline's
on-board phones (and pay their outrageous rates)?

Forcing you to use the Airphones is the least of the FAA's or the FCC's
concern.

The real reason is that the cellular phone industry does not want you
to. Their bread and butter is the ground based caller, and their
systems are not designed to work with callers that have some altitude on
the system (there are techncial deficiencies in this that I won't go
into unless you really want to know). As a matter of fact, the cellular
industry fought a company who wanted to share the spectrum
tooth-and-nail over airborne use.

Oddly, this prohibition is NOT written into the rules for the newer
wireless services (PCS, NEXTEL, etc...) that operate outside the AMPS
(800MHz) band. However, most of the carriers with these services still
discourate airborne use.

"Bob Chilcoat" wrote in message
...
I noticed on the evening news the other night that someone is trying to
get
a modular mobile "cell tower" approved that would be installed in
commercial
aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)


Still won't work. The frequency the cell in the air is on, will be hitting
dozens of towers on the ground, making them unable to use that frequency for
other users on the land.
--
Jim in NC


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.774 / Virus Database: 521 - Release Date: 10/7/2004

Actually it could work very well, and I have seen this proposal from
several different sources. The Idea is to install a low power cell
phone tower into the airliner.

As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

By installing the tower in the aircraft you are only a few hundred
feet from the tower (at the most). The Cell phones will get an
excellent signal from it and will drop to the lowest transmit power
setting, Thus the interference with towers on the ground should be
minimal.

I am not an expert on these, I am just repeating how it was explained
to me.

Brian

"Morgans" wrote in message ...
"Bob Chilcoat" wrote in message
...
I noticed on the evening news the other night that someone is trying to
get
a modular mobile "cell tower" approved that would be installed in
commercial
aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)


Still won't work. The frequency the cell in the air is on, will be hitting
dozens of towers on the ground, making them unable to use that frequency for
other users on the land.

Brian Case wrote:


As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

The cellular phone does use an adaptive power control (it's not tied to
the signal strength bar).

The problem is that even at mimimal power, if you're sitting close to
the window, you can be heard equally well by a large number of cells
over the system. There's nothing magic that they can do to stop this
short of rf shielding the aircraft windows somehow.

"Brian Case" wrote in message
om...
Actually it could work very well, and I have seen this proposal from
several different sources. The Idea is to install a low power cell
phone tower into the airliner.

As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

By installing the tower in the aircraft you are only a few hundred
feet from the tower (at the most). The Cell phones will get an
excellent signal from it and will drop to the lowest transmit power
setting, Thus the interference with towers on the ground should be
minimal.

I am not an expert on these, I am just repeating how it was explained
to me.

Brian
I could see the possibilities of strong enough signal not reaching the
ground to cause problems, but......

Which company (Of the multitudes) will you have to belong to, to get your
phone to work? How will the plane's system communicate with the ground? By
cell tower? g
--
Jim in NC


---
Outgoing mail is certified Virus Free.
Checked by AVG anti-virus system (http://www.grisoft.com).
Version: 6.0.774 / Virus Database: 521 - Release Date: 10/7/2004

The only thing that I see wrong with this is that the cell "tower" needs
to connect to the wired phone system. We know that it can't be
hardwired, that would be one hell of a long cable! So, as the "tower"
needs to transmit and receive (transceiver) from other transceivers on
the ground that are hardwired to the phone system. You can put the
ground transceivers on a different frequency pairs, but that's a whole
new world wide system!

Brian Case wrote:

Actually it could work very well, and I have seen this proposal from
several different sources. The Idea is to install a low power cell
phone tower into the airliner.

As I understand it that signal bar you see on you Cell phone is
dictates how much power the cell phone uses to transmit. So the closer
you are to the tower the less power it uses to transmit. This is why
you phone batteries probably last longer in town than the do out in
the boondocks.

By installing the tower in the aircraft you are only a few hundred
feet from the tower (at the most). The Cell phones will get an
excellent signal from it and will drop to the lowest transmit power
setting, Thus the interference with towers on the ground should be
minimal.

I am not an expert on these, I am just repeating how it was explained
to me.

Brian

"Morgans" wrote in message ...

"Bob Chilcoat" wrote in message
...

I noticed on the evening news the other night that someone is trying to

get

a modular mobile "cell tower" approved that would be installed in

commercial

aircraft so that passengers can use their own mobile phones. It will be
interesting to see how the FCC and FAA handle this one.

--
Bob (Chief Pilot, White Knuckle Airways)


Still won't work. The frequency the cell in the air is on, will be hitting
dozens of towers on the ground, making them unable to use that frequency for
other users on the land.

Brian Case wrote:

Actually it could work very well, and I have seen this proposal from
several different sources. The Idea is to install a low power cell
phone tower into the airliner.

Well, it would work well, but not if they actually used the cellular frequencies
(AMPS). If they installed a PCS processor in the plane, modern PCS phones would
communicate with it and not fall back on the AMPS frequencies.

George Patterson
If a man gets into a fight 3,000 miles away from home, he *had* to have
been looking for it.

"Ron Natalie" wrote in message
m...
DaveC wrote:
Cell phone usage is restricted on all domestic commercial flights by the
FAA,
so the flight attendant keeps telling me.

Nope. The FAA rules have not changed on this, nor have the FCC ones.
You can't use Advanced Mobile Phone Service (i.e., traditional cellular)
airborne. That is an FCC rule.

The FAA rule is just that the airline (i.e., the operator) must
determine when electronic devices are safe to use. The only thing that
has really changed is the "conventional wisdom" on the FAA's part got a
little tighter after some supposed interference issues (primarily blamed
on laptops) a few years back.

Is cell phone usage also restricted on private jets, etc. for similar
reasons?

Yes, all airborne use is prohibited. On cell phones permanently
installed on private jets, there has to be a warning label attached to
prohibit it's use in the air. (FCC rule).

So my question... what is the technical reason for restriction of cell
phone
us on commercial flights? Is this reason valid, technically? Or is it
simply
an excuse to force anyone who needs to make a call to use the airline's
on-board phones (and pay their outrageous rates)?

Forcing you to use the Airphones is the least of the FAA's or the FCC's
concern.

The real reason is that the cellular phone industry does not want you
to. Their bread and butter is the ground based caller, and their
systems are not designed to work with callers that have some altitude on
the system (there are techncial deficiencies in this that I won't go
into unless you really want to know). As a matter of fact, the cellular
industry fought a company who wanted to share the spectrum
tooth-and-nail over airborne use.

Oddly, this prohibition is NOT written into the rules for the newer
wireless services (PCS, NEXTEL, etc...) that operate outside the AMPS
(800MHz) band. However, most of the carriers with these services still
discourate airborne use.

Later this month an industry group is going to announce standards and an
icon that will come on to show that a device that is not in a transmit mode,
even if it is turned on for other uses.