Re: [time-nuts] FreeBSD version
Hi Tom,
There are new EMC standards and HIRF too. But that still leaves the legacy aircraft flying around. If you made the rules retrospective it would push the cost of flying up considerably. Most people don't want to know that the aircraft they are in is older than any car they would consider for everyday use!
Robert G8RPI.
--- On Sun, 4/10/09, Thomas A. Frank ka2cdk@cox.net wrote:
From: Thomas A. Frank ka2cdk@cox.net
Subject: Re: [time-nuts] GPS from a window seat
To: "Discussion of precise time and frequency measurement" time-nuts@febo.com
Date: Sunday, 4 October, 2009, 9:28 PM
I have read that there have been studies with a spectrum
analyzer system on planes that have shown that compliance with the no
radiating device rules and electronics off during takeoff and landing is
far less than 100% though I certainly would not personally deliberately
violate the law whether or not the probability of it causing a problem
is significant. Apparently one or two cellphones can be seen registering
with cell systems during takeoff and landing on many flights - probably
most of them unintentionally left on.
Which is why the onus should be on the aircraft manufacturers to make certain that there is no potential for life threatening danger from electronic devices.
A blanket ban is the usual response from a bureaucracy to something that they cannot actually control, and which they do not wish to put the effort into correcting.
But that doesn't change the fact that if a drunk businessman or a bored 6 year old with a new toy can stealthily endanger all the passengers on a plane, the responsibility - and liability - should be with the aircraft designer.
Bringing it back to the normal topic at hand, I wonder - if you had a radio receiver tuned to WWV, and a GPS with a 1pps, if you could see the relativistic effect of flying at 500 knots at 30K feet and log it on your computer?
Tom Frank, KA2CDK
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Hi
There is of course a non technical, non EMC reason for such a ban. Security. It might be considered that exact position and speed information could be of use to a passenger with ill intent. Note that most airlines turn of the moving map on the descent.
Robert G8RPI.
--- On Mon, 5/10/09, Keith E. Brandt, WD9GET wd9get@amsat.org wrote:
From: Keith E. Brandt, WD9GET wd9get@amsat.org
Subject: Re: [time-nuts] GPS from a window seat
To: "Discussion of precise time and frequency measurement" time-nuts@febo.com
Date: Monday, 5 October, 2009, 1:02 AM
See Joe Mehaffey's list of airlines at
[1]http://gpsinformation.net/airgps/airgps.htm
The list of airlines that allow GPS have the caveat that the Captain has the
final decision.
It is interesting that American is listed as banning them as of
October 2009 (apparently they have switched back and forth on this
policy)...
Earlier this week the Mehaffy list had American as approving GPS, but I
checked the AA website earlier this week and it listed them as being
banned. I contacted Mehaffey and maybe he updated the list after
contacting AA. I'm flying AA this coming Friday, so I'll see how it
goes. I flew up on Delta and used my Garmin Legend HCx in a window seat
and it worked beautifully. My next leg was on a United Shuttle, and
despite their website saying GPS was approved, the flight attendant
specifically announced that they were not approved. I didn't push it
since it was a 0.5 hr commuter flight.
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Col Keith E. Brandt, MD, MPH
Chief, Aerospace Medicine Consultation Division
Brooks City Base, San Antonio, Texas
[2]keith.brandt@gmail.com
Goodbye cruel world that was my home-
there's cleaner space out here to roam
Put my feet up on the moons of Mars-
sit back, relax, and count the stars
*This message transmitted with 100% recycled electrons
--
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Col Keith E. Brandt, MD, MPH
Chief, Aerospace Medicine Consultation Division
Brooks City Base, San Antonio, Texas
[3]wd9get@amsat.org
Goodbye cruel world that was my home-
there's cleaner space out here to roam
Put my feet up on the moons of Mars-
sit back, relax, and count the stars
*This message transmitted with 100% recycled electrons
References
1. http://gpsinformation.net/airgps/airgps.htm
2. mailto:keith.brandt@gmail.com
3. mailto:wd9get@amsat.org
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On Mon, Oct 5, 2009 at 12:15 AM, Robert Atkinson robert8rpi@yahoo.co.uk wrote:
Hi
There is of course a non technical, non EMC reason for such a ban. Security. It might
be considered that exact position and speed information could be of use to a passenger
with ill intent. Note that most airlines turn of the moving map on the descent.
And it might be that denying me coffee in the morning has severe
security repercussions. This hypothetical passenger with ill intent
would obey a "no gps" ban because...?
Not all gpses look like gpses. The globalsat ND100 looks like just
another thumb drive, lots of people have hacked a gps into netbooks.
Data loggers are featureless little blocks that fit neatly into a
shirt pocket.
I've seen a few people fiddling about with their personal
communicators on approach, and even more people playing with their
personal media players; it seems very unlikely that someone with
actual intent to do harm (rather than simple selfishness) would give
any consideration to a restriction on gps - aside from wondering when
the flight attendants will make their final cabin walk-through.
CK
(who'd rather see that cellphones be banned on aircraft because we
don't want to be stuck in a can for a couple of hours with people
blabbering loudly.)
--
GDB has a 'break' feature; why doesn't it have 'fix' too?
I can only draw on my experience in the past as
an avionics technician and Private PIC.
How about a different perspective on this?
Imagine that I bring aboard a "box of rocks" for
my entertainment. It may be magnetic, radioactive,
or some such. Now, these "rocks" could theoretically
influence the aircraft's navigation or communications
systems, but it "probably" won't, and no one has
been able to prove it ever caused an incident yet.
Now imagine that the majority of the passengers
are also unwilling to sit still for the duration
of the flight and have each brought their own boxes
of rocks to entertain themselves.
There should be no reason to be concerned, right?
You bet your life.
Why would you operate any device that might cause
a problem? Your life probably isn't worth that
cell phone call or PC application. And I am certain
that it isn't worth mine.
Chris Kuethe wrote:
On Mon, Oct 5, 2009 at 12:15 AM, Robert Atkinson robert8rpi@yahoo.co.uk wrote:
Hi
There is of course a non technical, non EMC reason for such a ban. Security. It might
Hi Mike,
I'm sorry but " Your life probably isn't worth that
cell phone call or PC application. And I am certain
that it isn't worth mine." Does not wash, witness the number of people who make cell calls while driving.
Furthermore Radioactive and magnetic materials have been banned for years. People who should now better still put hazardus items on aircraft. Witness ValuJet flight 592. It's normally about money.
Robert G8RPI.
EASA licenced aircraft engineer, Senior Avionics Designer, MRAeS.
--- On Mon, 5/10/09, Mike Naruta AA8K aa8k@comcast.net wrote:
From: Mike Naruta AA8K aa8k@comcast.net
Subject: Re: [time-nuts] GPS from a window seat
To: "Discussion of precise time and frequency measurement" time-nuts@febo.com
Date: Monday, 5 October, 2009, 9:13 PM
I can only draw on my experience in the past as
an avionics technician and Private PIC.
How about a different perspective on this?
Imagine that I bring aboard a "box of rocks" for
my entertainment. It may be magnetic, radioactive,
or some such. Now, these "rocks" could theoretically
influence the aircraft's navigation or communications
systems, but it "probably" won't, and no one has
been able to prove it ever caused an incident yet.
Now imagine that the majority of the passengers
are also unwilling to sit still for the duration
of the flight and have each brought their own boxes
of rocks to entertain themselves.
There should be no reason to be concerned, right?
You bet your life.
Why would you operate any device that might cause
a problem? Your life probably isn't worth that
cell phone call or PC application. And I am certain
that it isn't worth mine.
Chris Kuethe wrote:
On Mon, Oct 5, 2009 at 12:15 AM, Robert Atkinson robert8rpi@yahoo.co.uk wrote:
Hi
There is of course a non technical, non EMC reason for such a ban. Security. It might
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Group,
Completed circumnavigation of the world via Singapore with a hand-held
Garmin 60 CSx GPS receiver.
Set it to record at 6 minute intervals, and marked waypoints. Used about 6%
of track space with 4 GB micro SD card.
Had no trouble with aircraft interference. Talked to the Captain after a 4
hour flight from MSP to LAX. He said he had no problems, and thinks GPS
receivers are quite safe. He worries about active transmitters, like cell
phones and wireless laptops.
Had no trouble getting a lock at altitude and speed. Didn't have a window
seat in the A380 from Singapore to London. About 2/3 of the way through,
over the Ukraine, I found a window I could stand by. Took about 2 minutes to
lock. Last lock was in Singapore.
Had no trouble with getting 20 foot accuracy with the receiver in a jacket
pocket near the window. Can get 10 foot accuracy when stationary. Could go
to 40 feet in some satellite configurations. Close enough for recording a
trip.
There was some discussion of hand held devices being crippled for aviation,
so that aviation units could be sold for more money. The 60 CSx will not
display GPS altitude. It only uses a barometric sensor, which gives you
cabin pressure. OTOH, the compass display uses GPS if you are moving, and
magnetic when you are standing still. No problem for a map of the course.
Cabin pressure will tell you when you have landed or leaped into the sky.
Very impressed with the performance of the receiver and antenna in that
device. Newer units don't have an antenna stub, so they may not have the
response of the 60 CSx.
Also useful for setting your watch. But you can get several inexpensive
watches and preset them for the cities that you will visit. As you are
landing, change to another watch. Saw an oil executive do that in the
Concorde in '83, with expensive watches.
That was my experience. YMMV.
Bill Hawkins