On 10/17/2010 12:31 PM, Mike the Strike wrote:
On Oct 17, 5:14 am, Mike
wrote:
On 10/17/2010 4:43 AM, Mark Dickson wrote:
Sorry, but thermalling gliders will almost always show on radar.
At 23:39 16 October 2010, John Smith wrote:
Mark Dickson wrote:
No, it's Ryanair. They always look for direct routings, even if it
takes them outside controlled airspace.
They can ask as much as they want, it's the controller authority to
allow it or not. But how can I explain this to somebody who
doesn't even
know that class E airspace is controlled?
Contrary to popular myth, gliders show
as a primary return on radar displays
Contrary to popular myth, stationary primary targets are filtered
out by
the radar software, hence thermalling gliders don't show on the
controller's display.
Even if non-equipped gliders show up, there is no altitude info. In the
US, standard procedure is that IFR traffic is not routed around VFR
airplanes, even if they are transponder equipped. If you are lucky, the
IFR traffic will get a traffic advisory. Keep your fingers crossed that
the IFR traffic has TCAS and that the pilots follow the RA instructions.
--
Mike Schumann
At least in Tucson, I believe that ATC does route IFR traffic away
from transponder-equipped gliders. We have a unique squawk code and,
at least from my observations, controllers keep airliners well away
from gliders so equipped. When my transponder was down for repair, I
got to see a lot of aircraft really close up!
Of course, the unintended consequence is that airliners diverted from
around me are often sent through nearby thermals where some of my non-
transponder equipped colleagues are soaring.
Mike
It's great that your local controllers are doing this. It needs to
happen everywhere. See this study by MIT's Lincoln labs from 2005:
http://www.ll.mit.edu/publications/j...2_04Kuchar.pdf
See pages 287-288. There were an average of 9 TCAS RAs per DAY within
60 miles of the Lincoln Labs sensor in Boston. This is a direct result
of ATC not vectoring traffic around transponder equipped GA aircraft,
and effectively using TCAS as the primary VFR / IFR collision avoidance
system.
--
Mike Schumann