John,

I've read your review of the various PCAS (same as TPAS) devices. I use the
Proxalert R-5 and would add to your comments re this unit.

You are correct, it does not have internal batteries and so needs ship's
power. This has not been much of an issue for me - - install the wire and
plug once, don't have to change batteries.

It does hang down some 3/4" below the glare shield. This allows it to have a
good sized display, while not blocking forward view. In my ASH26E, it sits
on the glareshield and doesn't block the view of the upper portion of the
panel (this area is already blocked by the glare shield "brow", nor does it
block forward view at all.

The Proxalert is the only unit I'm aware of that displays threat aircraft
squawk code. This is important to me as the threat level from a 1200 squawk
aircraft, all other things being equal, is much higher than that from a
discreet squawking aircraft. The discreet squawking aircraft is talking to
ATC and probably has been told of my presence (I use a transponder).

If the host, PCAS glider, has no transponder, then I guess it doesn't much
matter what the threat aircraft is squawking - - not likely he is aware of
you in any case!

I have heard complaints from some R-5 owners that their unit did not alarm
reliably or was inconsistent. I've not had that problem with mine at all. It
finds traffic that I otherwise wouldn't see, some of which I never do see
(g). When I'm talking to ATC getting flight following, the R-5 display is
remarkably consistent with their advisories.
--
bumper ZZ (reverse all after @)
"Dare to be different . . . circle in sink."
Quiet Vent kit and MKII yaw string
"jcarlyle" wrote in message
oups.com...
I fly with a PCAS, Randy. I bought it because my glider club lies
inside the Mode C veil of PHL, because an active military air base is 5
miles away, and because there are several airways that lie within
several miles of us.

It has gone off several times during each of the 5 flights that I've
had it in my glider. As I get height and distance readings, it is
usually pretty easy to spot the traffic. Once I had difficulty finding
the threat, and it turned out to be a commuter running through the
clouds above me. I wasn't too worried, because the MRX indicated that
he was level and 600 feet higher than me, but if he had been descending
I would have been sweating big time!

Incidentally, I did a review of the various PCAS units available; you
can read the discussion he http://tinyurl.com/pcmkw

-John

wrote:
PCAS - Portable Collision Avoidance System
http://www.zaonflight.com/mrx.html
Is there anyone out there using this system in their glider?

From what I have read, it seems like a like a pretty nice system to
at least make you aware of what fast moving traffic is approaching
your current airspace.
If you think that an airliner in going to spot you just because
you have a transponder, is a very false security.
I fly a Boeing jet for a living and at times it is very hard to see
another jet that ATC and TCAS alerted us to.

When I flew my glider in Moriarty last June, I was amazed at the number
of large jets coming in from the east passing above and below me.
I was talking and listening to ABQ approach control. ACT gave the
approaching traffic my position and altitude and none of the airliners
could look visually locate me. I saw all of them. I am sure that most
of these pilots are running their descent and approach check lists,
doing an approach briefing and saying a few last words to the
passengers.

At work when we get below 18,000 feet, I am always looking for gliders
below the base of the clouds. I have never seen a glider in over
19 years of flying, but I know that they are there. I am hoping that
they see me.
It seems to me that a PCAS type of system would help me locate
a majority of the biggest and fastest moving threats in the sky,
commercial airliners, corporate jet and higher-end general aviation
aicraft).

Any PCAS users out there?

Randy