WTF??

wrote:
On Aug 17, 6:09 pm, (Paul Tomblin) wrote:
In a previous article, NoneYa said:

CINCINNATI
For the second time in six months, a primary
radar failure Sunday morning at Cincinnati Tower (CVG) and
Terminal Radar Approach Control (TRACON) and lack of
appropriate secondary radar feeds severely delayed scores of
flights into and out of the nation's 14th-busiest airport at
the beginning of a morning rush hour period. It also exposed
again the lack of Federal Aviation Administration action to
But don't worry, because the airlines will still blame GA.

--
Paul Tomblin http://blog.xcski.com/
``Furthermore, [your wishlist item] would end up being the sort of system
feature that we in software engineering call an "SPR generator".''
- Paul S. Winalski

Of course it was GA's fault... all those spam cans reflect a lot of
radar energy and overloaded the primary radar system causing it to go
down. Then all those 1200 transponder codes overflowed the input
buffer on the secondary system, causing the feed to lock up. This
would be easily solved by implementing user fees. With high enough
user fees, all those transponders would be turned off instead of
broadcasting 1200, and the spam cans would be flying at tree top level
to avoid detection, which would prevent the primary radar from going
down.

See, simple cause and effect...

Dean W
AeroLEDs LLC
www.aeroleds.com

When you use ancient technology like the FAA the comment
about system overload is real and not a joke. The FAA ground
DME stations routinely overload at major airports(Atlanta is
real bad) because the ancient ITT equipment in the FAA
facilities was only designed to simultaneously interrogate
about 150 aircraft at a time.

After that threshold is reached the system begins to
throttle back and drop targets at the outer range of the DME
equipment. In technical terms the "reply efficiency" drops.

So the sarcasm does have some validity. The FAA and their
outdated equipment is overloaded. However, under the
umbrella of political correctness the FAA now is filled with
unqualified people satisfying politically correct goals and
the result is a Government organization that was once like
NASA more like HUD.

If not for the technical innovations in the cockpit our Air
Traffic system in America would be more like Africa.

So, the sarcasm is valid

On Sat, 18 Aug 2007 11:50:00 -0400, NoneYa
wrote:


When you use ancient technology like the FAA the comment
about system overload is real and not a joke. The FAA ground
DME stations routinely overload at major airports(Atlanta is
real bad) because the ancient ITT equipment in the FAA
facilities was only designed to simultaneously interrogate
about 150 aircraft at a time.

After that threshold is reached the system begins to
throttle back and drop targets at the outer range of the DME
equipment. In technical terms the "reply efficiency" drops.

How does the system know which are the outer dme "targets"? Is it
just the weaker dme transmissions that are received by the ground
station that are dropped? Stan

In a previous article, said:
How does the system know which are the outer dme "targets"? Is it
just the weaker dme transmissions that are received by the ground
station that are dropped? Stan

By response time. It sends out a signal, and the first N to respond are
tracked.

--
Paul Tomblin http://blog.xcski.com/
"Whoah, whoah! A fat sarcastic Star Trek fan? You must be a devil with the
ladies!" - Simpsons

On Sun, 19 Aug 2007 14:23:44 +0000 (UTC),
(Paul Tomblin) wrote:

In a previous article, said:
How does the system know which are the outer dme "targets"? Is it
just the weaker dme transmissions that are received by the ground
station that are dropped? Stan

By response time. It sends out a signal, and the first N to respond are
tracked.
I thought you were referring to DME navaids. Now I understand. I
presume DME navaids must have a limiting number of units they can
respond to too? Stan

wrote:
On Sun, 19 Aug 2007 14:23:44 +0000 (UTC),
(Paul Tomblin) wrote:


In a previous article, said:

How does the system know which are the outer dme "targets"? Is it
just the weaker dme transmissions that are received by the ground
station that are dropped? Stan

By response time. It sends out a signal, and the first N to respond are
tracked.

I thought you were referring to DME navaids. Now I understand. I
presume DME navaids must have a limiting number of units they can
respond to too? Stan

I believe he was commenting about DME. I believe the high volumne
facilities can handle 200 aircraft at a time.

In article , B wrote:

I thought you were referring to DME navaids. Now I understand. I
presume DME navaids must have a limiting number of units they can
respond to too? Stan

I believe he was commenting about DME. I believe the high volumne
facilities can handle 200 aircraft at a time.

The usual means for DME transponders to limit the maximum number of replies
sent out is by reducing the receiver sensitivity so that weaker interrogations
are rejected. This does not necessarily mean that the more distant aircraft
are dropped since airborne interrogaters have different power levels. For
example, my KN-64 is 100 watts (iirc) while the TSO'd KN-62 is 200 watts.

Specifications for DME ground stations are usually expressed in terms of
maximum number of interrogations and replies.

--
Bob Noel
(goodness, please trim replies!!!)

"Paul Tomblin" wrote in message ...
In a previous article, said:
How does the system know which are the outer dme "targets"? Is it
just the weaker dme transmissions that are received by the ground
station that are dropped? Stan

By response time. It sends out a signal, and the first N to respond are
tracked.

--
No, Paul, the DME ground station does not initiate the exchange.
The ground stations only reply to interrogations from aircraft.
See Bob Noel's correct explanation elsewhere in this thread.
When the ground station is not being interrogated, it increases
its receiver sensitivity until it "replies" occasionally to random noise.
As more actual interrogations are received, the ground receiver
reduces its sensitivity to limit the rate of replies transmitted.

On Aug 19, 10:55 am, "John R. Copeland"
wrote:
"Paul Tomblin" wrote in ...
In a previous article, said:
How does the system know which are the outer dme "targets"? Is it
just the weaker dme transmissions that are received by the ground
station that are dropped? Stan

By response time. It sends out a signal, and the first N to respond are
tracked.

--

No, Paul, the DME ground station does not initiate the exchange.
The ground stations only reply to interrogations from aircraft.
See Bob Noel's correct explanation elsewhere in this thread.
When the ground station is not being interrogated, it increases
its receiver sensitivity until it "replies" occasionally to random noise.
As more actual interrogations are received, the ground receiver
reduces its sensitivity to limit the rate of replies transmitted.

Back when I was about 18 years old I had a guy on a construction crew
tell me that his radar detector worked by sending out a beam which
intercepted the beam of the cops radar and that is how it detected
it. When I tried to explain that it didn't work like that, but simply
received reflected signals which is why it could detect a cop over a
hill, he dismissed my explanation and stubbornly stuck to his
idea... :-)

wrote:
On Aug 19, 10:55 am, "John R. Copeland"
wrote:
"Paul Tomblin" wrote in ...
In a previous article, said:
How does the system know which are the outer dme "targets"? Is it
just the weaker dme transmissions that are received by the ground
station that are dropped? Stan
By response time. It sends out a signal, and the first N to respond are
tracked.
--
No, Paul, the DME ground station does not initiate the exchange.
The ground stations only reply to interrogations from aircraft.
See Bob Noel's correct explanation elsewhere in this thread.
When the ground station is not being interrogated, it increases
its receiver sensitivity until it "replies" occasionally to random noise.
As more actual interrogations are received, the ground receiver
reduces its sensitivity to limit the rate of replies transmitted.

Back when I was about 18 years old I had a guy on a construction crew
tell me that his radar detector worked by sending out a beam which
intercepted the beam of the cops radar and that is how it detected
it. When I tried to explain that it didn't work like that, but simply
received reflected signals which is why it could detect a cop over a
hill, he dismissed my explanation and stubbornly stuck to his
idea... :-)


Sigh...Some people are just stupid. You can't fix stupid!

-----Original Message-----
From: NoneYa ]
Posted At: Monday, August 20, 2007 10:06 AM
Posted To: rec.aviation.ifr
Conversation: WTF??
Subject: WTF??

....

Sigh...Some people are just stupid. You can't fix stupid!

I very much like my wall sign that reads "It's too bad stupid isn't
painful!" I had to bring it home - they wouldn't let me leave it
displayed at the office. I figure it was too much of a threat to middle
management.