Sectional use

Jay Honeck writes:
The 496 displays terrain quite nicely. I haven't upgraded the
software in our 2000c to do so, but it has the same capability. (Of
course, most of our "terrain" worries are towers, here in the
Midwest...)

Mxsmanic wrote:
I thought it was bad form to look at the little GPS screen when you're
supposed to be looking out the window.

It's not bad to *look* at the little GPS screen, it's bad to be
*fixated* on it.

Recently, Tony posted:

Nothing, absolutely nothing, replaces a sweaty finger on a sectional
while doing pilotage. My favorite use of them, though, is to give them
to a pax and let them track my navigation if the weather is clear
enough.

I can't remember the last time I used one in real life for navigation,
but for flight planning they are convenient for chosing airports close
to where ever it was I was going. In the good old days, for example,
it would help me choose between Midway and (was it Burke?) Lakefront
in Chicago, depending on where in the city I was going.

Burke Lakefront is in Cleveland, so it would be hard to choose it on the
same sectional as Midway. ;-)

You probably meant Meigs...

Neil

Jay Honeck writes:

That's an interesting (if appalling) topic.

I think it is a real risk, but it would depend on the personality of
the bad guys. Unfortunately, it's quite feasible technically. The
U.S. military already has effective "area denial" (local jamming)
technology for GPS, and by now someone has certainly stolen it.

I wonder why no one (to
my knowledge) has ever taken out an ILS transmitter -- or, worse,
jammed it to cause false readings -- in an effort to do the same
thing?

The bad guys probably just aren't that sophisticated, and perhaps they
lack imagination, just as the good guys do.

A single ILS wouldn't be as damaging as jamming or spoofing GPS over a
populated area. And since civilian GPS is not encrypted, it is
particularly vulnerable to this. You just replace the satellite and
WAAS signals and direct an aircraft anywhere you want.

This is vastly harder to do with VORs, because there are so many of
them, the signal is simpler and stronger, and so on.

If you think about what this would do at, for example, Chicago's
O'Hare International, with planes landing at better than one per
minute, the results could be truly appalling.

Exactly. That's one reason why I wouldn't trust GPS entirely, even
when it seems to be working perfectly.

You could literally (in theory) steer a dozen jumbo jets into the
ground during a snow storm before anyone caught on... Yet, it's not
been done.

Yup.

Have Osama's buddies just not thought of this yet, or are we talking
about something that is much harder to accomplish than we might
assume?

I don't think they've thought of it. Hopefully they don't read this
newsgroup. And hopefully someone in the government has thought of it,
and is working on it, instead of all the dog-and-pony shows of useless
security that wastes so much time and effort and eats so deeply into
civil liberties now.

--
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Martin Hotze writes:

GPS jamming is only done by those operating the GPS satellites.

Anyone with the right equipment can jam the signal, and it can be done
from the ground.

Don't know how the
receiver will react when one signal (out of how many?) is out of scope.

All the signals can be spoofed within a specific area by the right
equipment.

And: What alert level you think would bring another terrorist act? They
already won. Shock and awe, you know.

They won as soon as they generated the hysteria and loss of civil
liberties that they had targeted. They had the government to help
them, which has the same objectives but for different reasons (the
government likes to increase power whenever possible).

Terrorism requires acts that are spectacular, since terrorists don't
have the means to do things that are actually highly damaging in an
objective sense. So exploding things is much more popular than, say,
embezzlement. But multiple plane crashes might have enough of a
Hollywood flavor to appeal to terrorists.

--
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Bob Noel writes:

Unlikely. There are field monitors and most jumbos would have radar
altimeters (or radio altimeters or whatever the heck they are called).

Famous last words. The USA had gate security before 9/11, and that
was supposed to stop the bad guys.

--
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Roy Smith writes:

Someday, you'll be flying an approach and the box will pop up with, "We're
sorry, but our account records show you have only subscribed to the
non-precision plan. If you would like to continue to track the glideslope,
please swipe your credit card now".

Yes, I worry about that, too. Imagine the screen going blank because
you forgot to "activate" it for the month with a credit card before
departing.

Unfortunately, this scenario isn't as farfetched as it sounds. Just
look at all the DRM junk in Vista and you can see where the world is
heading.

--
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On Sun, 28 Jan 2007 17:41:41 +0100, Mxsmanic wrote:

GPS jamming is only done by those operating the GPS satellites.

Anyone with the right equipment can jam the signal, and it can be done
from the ground.

yes. I meant: right now it is only done by those operating the satellites.

Don't know how the
receiver will react when one signal (out of how many?) is out of scope.

All the signals can be spoofed within a specific area by the right
equipment.

I can't argue on that due to lack of knowledge on this topic. ah, well,
thanks to wikipedia:
http://en.wikipedia.org/wiki/Global_...em#GPS_jamming
and:
---snip
According to John Ruley, of AVweb, "IFR pilots should have a fallback plan
in case of a GPS malfunction".
---snap

as for the terrorists: no idea how much effort, skill, money and time you
need. And how big the jammers are. *gooogle* oh, here is a GPS jammer
cookbook: http://www.phrack.org/archives/60/p60-0x0d.txt *g*

Terrorism requires acts that are spectacular, since terrorists don't
have the means to do things that are actually highly damaging in an
objective sense. So exploding things is much more popular than, say,
embezzlement. But multiple plane crashes might have enough of a
Hollywood flavor to appeal to terrorists.

So pouring 1 gallon of $pickyourfavouritepoison into the water basin of a
small town would do the trick. It will show that rural areas can be hit
("nobody is safe!") too and you have Hollywood-like szenes (hey, they
already have done films on such topics). This is much cheaper, low tech and
takes so much less effort than jamming GPS signals.

disclaimer: I am NOT a terrorist.

#m
--
I am not a terrorist. http://www.casualdisobedience.com/

Martin Hotze writes:

yes. I meant: right now it is only done by those operating the satellites.

Actually, some other parties have developed jamming capabilities.
Mostly governments, IIRC, but it's pretty much inevitable that it has
already fallen into private hands.

So pouring 1 gallon of $pickyourfavouritepoison into the water basin of a
small town would do the trick.

There isn't any poison toxic enough to work with only one gallon, if
the water supply is of any significant size (it would work for a well,
though).

But overall the idea is to do something spectacular and highly
visible, even though it may not do much objective damage. 9/11 is a
typical example of this: the actual objective impact of the attack was
vastly smaller than the psychological impact.

Terrorists do this because they simply don't have the means to win
with real firepower. If they have real military capability, they just
attack in the classic way instead, with aircraft and tanks and so on.
Indeed, sometimes the only difference between the two groups is that
one has the means to maintain and use a standing military, and the
other doesn't.

This is much cheaper, low tech and
takes so much less effort than jamming GPS signals.

Maybe. It doesn't take much to make people hysterical, especially in
areas where the mass media fan the flames. It's interesting that
terrorists, the government, and the media all have somewhat different
goals, but the very same acts serve their purposes. A terrorist
attack is a win for the terrorists, a win for the government (it can
keep a president in office, for example), and a win for the media
(fodder for creating Fear, Uncertainty, and Dread, the essential
prerequisites to revenue).

Anyway, it's not a good idea to rely too much on GPS, or on any other
one navigation method.

I just finished flying from the Grand Canyon to Phoenix by VORs with a
chart, just to stay in practice. I kept the GPS turned off. It works
just fine, and I'm not sure that it's that much more tedious than
using a GPS.

--
Transpose mxsmanic and gmail to reach me by e-mail.

You're right, I was thinking of Miegs. I lov3ed landing there and
walking to conventions at McCormick (did I get that right?) place. Did
the same thing at Atlantic City, it was something like Bader Field
that was about a mile from the boardwalk -- an OK walk in the daytime,
but probably a walk to eternity if taken at late night.

On Jan 28, 11:26 am, "Neil Gould" wrote:
Recently, Tony posted:

Nothing, absolutely nothing, replaces a sweaty finger on a sectional
while doing pilotage. My favorite use of them, though, is to give them
to a pax and let them track my navigation if the weather is clear
enough.

I can't remember the last time I used one in real life for navigation,
but for flight planning they are convenient for chosing airports close
to where ever it was I was going. In the good old days, for example,
it would help me choose between Midway and (was it Burke?) Lakefront
in Chicago, depending on where in the city I was going.Burke Lakefront is in Cleveland, so it would be hard to choose it on the
same sectional as Midway. ;-)

You probably meant Meigs...

Neil

"Jay Honeck" wrote

That's an interesting (if appalling) topic. I wonder why no one (to
my knowledge) has ever taken out an ILS transmitter -- or, worse,
jammed it to cause false readings -- in an effort to do the same
thing?

Taking out the transmitter would probably be nothing more than a minor and
temporary annoyance (a runway switch). Creating a false signal that
overrides the main signal well enough to fool someone - not practical and
probably not possible to pull it off without someone noticing.

Same holds true for airborne GPS in my opinion. Jamming the signals - not
too effective if earth-based (GPS are line-of-sight transmissions that
cannot penetrate objects). Creating a false signal to "fool" an airborne
receiver - not practical or economically feasible.

You could literally (in theory) steer a dozen jumbo jets into the
ground during a snow storm before anyone caught on... Yet, it's not
been done.

Doubtful - you don't follow an ILS signal blindly. There are cross checks
you can (and should) make along the way.

BDS