Feds Want to Equipe Gliders With Transponders and Radios

On Apr 29, 5:51*am, Larry Dighera wrote:


I would guess the controller would need to adjust his scope from it's
usual setting to see primary targets, so a radio call may be
necessary. *While a corner reflector would doubtless increase the
radar energy returned to the radar antenna and provide a brighter
primary target, I doubt that would be sufficient to cause the glider
so equipped to become visible on ATC's scopes without reconfiguring
them to display slow-moving primary targets.


How slow does a target need to be to be undisplayed -typically? I
would have thought that even a glider is fast (45 knots) compared to
usual clutter.

Cheers

On Mon, 28 Apr 2008 12:49:07 -0700 (PDT), WingFlaps
wrote in
:

On Apr 29, 5:51*am, Larry Dighera wrote:


I would guess the controller would need to adjust his scope from it's
usual setting to see primary targets, so a radio call may be
necessary. *While a corner reflector would doubtless increase the
radar energy returned to the radar antenna and provide a brighter
primary target, I doubt that would be sufficient to cause the glider
so equipped to become visible on ATC's scopes without reconfiguring
them to display slow-moving primary targets.


How slow does a target need to be to be undisplayed -typically? I
would have thought that even a glider is fast (45 knots) compared to
usual clutter.


I have no idea, but just assumed it was a tunable parameter.

Perhaps one of the ATC folks among the readership of these newsgroups
may offer some input on that subject.

In rec.aviation.soaring WingFlaps wrote:
On Apr 29, 5:51?am, Larry Dighera wrote:

I would guess the controller would need to adjust his scope from it's
usual setting to see primary targets, so a radio call may be
necessary. ?While a corner reflector would doubtless increase the
radar energy returned to the radar antenna and provide a brighter
primary target, I doubt that would be sufficient to cause the glider
so equipped to become visible on ATC's scopes without reconfiguring
them to display slow-moving primary targets.

How slow does a target need to be to be undisplayed -typically? I
would have thought that even a glider is fast (45 knots) compared to
usual clutter.

A cruising glider is likely to be faster than that. However, gliders
climbing in a thermal are making tight little circles, and I believe this
will look like a stationary target to the radar. Worse, a glider climbing
in wave really will *be* stationary, as the glider will try not to move by
matching airspeed to wind speed at altitude. I have heard stories of
unintelligent GPS units deciding the airplane was parked and shutting
themselves off in this situation.

--
Michael Ash
Rogue Amoeba Software

"WingFlaps" wrote in message
...

How slow does a target need to be to be undisplayed -typically? I
would have thought that even a glider is fast (45 knots) compared to
usual clutter.


There are two windmill farms about twenty miles northeast of Green Bay that
break through the Moving Target Indicator. The windmills are stationary, of
course, but the moving rotors are detected.

In article ,
WingFlaps wrote:

How slow does a target need to be to be undisplayed -typically? I
would have thought that even a glider is fast (45 knots) compared to
usual clutter.

Don't forget that it's the radial velocity that is detected by skin paint.

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

On May 4, 8:37*am, Bob Noel
wrote:
In article ,

*WingFlaps wrote:
How slow does a target need to be to be undisplayed -typically? I
would have thought that even a glider is fast (45 knots) compared to
usual clutter.

Don't forget that it's the radial velocity that is detected by skin paint.



Aha, someone who understands Dopplewho knows!. data from the secondary
sites can fix that problem.

Cheers

In rec.aviation.piloting WingFlaps wrote:
On May 4, 8:37?am, Bob Noel
wrote:
In article ,

?WingFlaps wrote:
How slow does a target need to be to be undisplayed -typically? I
would have thought that even a glider is fast (45 knots) compared to
usual clutter.

Don't forget that it's the radial velocity that is detected by skin paint.



Aha, someone who understands Dopplewho knows!. data from the secondary
sites can fix that problem.

The FAA radars are what they are.

You can arm wave forever about what they could be, but that isn't going
to change them.


--
Jim Pennino

Remove .spam.sux to reply.

On Sat, 03 May 2008 23:15:03 GMT, wrote in
:



The FAA radars are what they are.

You can arm wave forever about what they could be, but that isn't going
to change them.

But decommissioning them, as part of the ADS-B implementation, will
make them moot.

Larry Dighera wrote:

On Sat, 03 May 2008 23:15:03 GMT, wrote in
:



The FAA radars are what they are.

You can arm wave forever about what they could be, but that isn't going
to change them.

But decommissioning them, as part of the ADS-B implementation, will
make them moot.

What is being lost? Primary radar is making a comeback after 2001, not
going away.

On Sat, 03 May 2008 20:15:32 -0400, Jennifer Allen
wrote in :



Larry Dighera wrote:

On Sat, 03 May 2008 23:15:03 GMT, wrote in
:



The FAA radars are what they are.

You can arm wave forever about what they could be, but that isn't going
to change them.

But decommissioning them, as part of the ADS-B implementation, will
make them moot.

What is being lost? Primary radar is making a comeback after 2001, not
going away.

I would enjoy reading supporting documentation for that assertion.


As this message thread refers to painting glider primary targets, it
would seem that post ADS-B, the FAA primary radars will be
decommissioned with the exception of those around the peripheral of
the US, hence my statement above.

http://72.14.253.104/search?q=cache:...ient=firefox-a
Decommissioning only the primary radar would result in both cost
avoidance (no upgrades) and maintenance cost-savings. Annual savings
estimates are approximately $30M per year. (Note: For purposes of
national defense, the primary radars around the peripheral of the
United States, would not be decommissioned in the near term).



http://astra.aero/downloads/ABIT/ABI...ting_final.pdf
The FAA envisions decommissioning. more than 300 en route radars. ...



http://www.fcw.com/print/12_23/news/94989-1.html
Radar is an outdated technology, the FAA says. Moving to ADS-B will
let the agency eventually decommission some of the current ground
radars. According to an FAA report, radar is imperfect and sometimes
has trouble distinguishing airplanes from flocks of birds or patches
of rain.



http://en.wikipedia.org/wiki/Automat...ance-broadcast
FAA segment 3 (2015-2020)

ADS-B In equipage will be based on user perceived benefit, but is
expected to be providing increased situational awareness and
efficiency benefits within this segment. Those aircraft who choose to
equip in advance of any mandate will see benefits associated with
preferential routes and specific applications. Limited radar
decommissioning will begin in the time frame with an ultimate goal of
a 50% reduction in the Secondary Surveillance Radar infrastructure.



http://www.faa.gov/about/office_org/...0-07_Final.pdf
Will there be a back-up system for ADS-B?

Yes, the FAA recognizes that a back-up system is needed in case of
problems with the satellite system. In 2006, a team from the FAA,
industry, and the military performed an analysis, taking into account
such things as the operational capability needed during an outage, the
length of time the back-up system would be expected to operate during
an outage, and any overlap between the back-up and ADS-B that would
result in a vulnerability. The agency adopted the team’s
recommendation to maintain about half the current network of
*secondary* radars as a back-up system in case of a GPS outage.