Any pireps for PCAS MRX collision avoidance system?

On Jun 4, 11:24 am, Thomas Borchert
wrote:
Andrew,

Do they work when there is no radar
facility nearby, or you are below the radar altitude?

Your targets must be hit by radar (or an active TCAS from an airliner),
not yourself. If that doesn't happen, the units don't work. How much
traffic will there be in such areas?


Since mid-air collisions occur near traffic patterns at low altitudes
this is where I would want the system to be most responsive. It seems
as if the opposite is true. Identifiying airplanes at cruise altitudes
might make someone feel better, but they are rarely a hazard. It would
be nice if there were a passive system that does not rely on a
transponder, like a laser radar.

A couple of week ago I heard; Glider-Glider-Glider, this is twin umpt-
upm, descending through 20,000 over the Pinenuts for landing at Carson
City.I responded that glider Jay Jay was descending through 10,000 on
the west side of the Pinenuts. About 3 minutes later the twin said,
Jay Jay, I have you on my TCAS and just got a visual on you about 500
feet below and 1 mile east of me. I responded, Roger that, I have you
on my PCAS and just got a visual on you also. We both agreed that this
was the way its supposed to work.
JJ



On Jun 3, 11:34 am, Mutts wrote:
Crossposting over to soaring...

worth 500 clams?..............http://www.zaonflight.com/content/view/2/13/

Some have commented that the lack of bearing info is a limitation,
others not so much.

Anyone with lots of experience using this unit or similar, thoughts?

Thanks!

On Fri, 1 Jun 2007 19:18:47 -0400, "Capt. Geoffrey Thorpe" The Sea
Hawk at wow way d0t com wrote:


"Mutts" wrote in message
.. .

worth 500 clams?..............

http://www.zaonflight.com/content/view/2/13/

Ax over on r.a.soaring - they seem to be more popular over there.- Hide quoted text -

- Show quoted text -

Our club, Black Forest Soaring Society (BFSS) now has five members
with the MRX PCAS. Mine is doing exactly what it is supposed to do:
detect transponder or TCAS equipped aircraft being interrogated near
my glider. two common things interrogate: a ground-based radar or
airborne TCAS. It is also portable so we can take it with us when we
teach or do intro rides in other planes.

There are two modes: advisory and alert.

Advisory is a two-beep warning that something is nearby and within my
preset altitude and distance criteria. Alert is a four-beep sound that
means the traffic is even closer.

I have been operating my PCAS with the screen at its lowest brightness
because it really is not important to me to know about traffic that is
relatively far from me. All I need is the noise: two-beeps or four;
that is, near or nearer.

That noise says it all since the criteria for activating those sounds
are set by the pilot, me.

When MRX beeps, my eyes sweeps (added the extra "s" to complete the
rhyme).

In the nine months I've owned the MRX, there have been four cases of
four-beeping. In all four cases, the traffic came from behind. And, in
all four cases I had plenty of time to search and locate the traffic.
The surprise traffic came from behind because MRX trained me to be
better at spotting traffic ahead and to my sides.

When I get rich, I'll also add a transponder. But for now, and
recognizing that jet guys are flying heads-down more often than even
they realize, PCAS is helping me a bunch. Oh, for a living I fly large
jets equipped with TCAS. I watch my fellow crewmembers and they don't
look out the window as often as they should.

So, I'd rather know that I can see most of them, then to hope that
they see me, and to hope that the Bonanza guys are talking to a radar
controller who will alert them to my presence.

Raul Boerner
LS6-B "DM"

wrote:

Advisory is a two-beep warning that something is nearby and within my
preset altitude and distance criteria. Alert is a four-beep sound that
means the traffic is even closer.

I'm also using an MRX. I believe it's warnings are also based distance
and altitude trends, not just distance and altitude. For example,
consider two aircraft the same distance from you and the same altitude
above, one descending and one ascending. Only the descending one will
trigger the alert signal.

In practice, I've found another glider can fly close to me going in the
same direction and not trigger the alert, but a more distant glider
coming at me will trigger the alert. Similar response when thermalling:
if we are both ascending at the same rate, no alert; if the lower glider
begins to gain on the higher glider, an alert may occur.

This more sophisticated threat determination seems to make it work well
in the traffic pattern when there are other aircraft around. My
experience in busy patterns is limited, however.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly
* "Transponders in Sailplanes" http://tinyurl.com/y739x4
* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

Eric wrote: I'm also using an MRX. I believe it's warnings are also
based distance and altitude trends, not just distance and altitude.
For example, consider two aircraft the same distance from you and the
same altitude above, one descending and one ascending. Only the
descending one will trigger the alert signal.

This "trend" clarification is a very important distinction. Thank you
for pointing it out. It helps to explain why sometimes aircraft are
within the MRX parameters, but don't trigger the beep-beeps.