Any pireps for PCAS MRX collision avoidance system?

The unit won't see other transponders, unless the other transponder is
interrogated by a TCAS-equipped aircraft.


Correct except for the last 4 words. ATC radar also intrerrogats
transponders.

Tony V.
http://home.comcast.net/~verhulst/SOARING

In article ,
Tony Verhulst wrote:

The unit won't see other transponders, unless the other transponder is
interrogated by a TCAS-equipped aircraft.


Correct except for the last 4 words. ATC radar also intrerrogats
transponders.

Note that I was responding to a poster discussing what happens
when you are below radar coverage.

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

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?

--
Thomas Borchert (EDDH)

Bob Noel wrote:


Note that I was responding to a poster discussing what happens
when you are below radar coverage.


Missed that. Thanks for the correction.

Tony

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"

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.

On Jun 4, 7:31 pm, Andrew Sarangan wrote:
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.

We don't need to dream about exotic technology, the stuff available
today does the job well enough to be very useful. Wherever you are
flying you are very likely to be being painted by TCAS, civil SSR
radar or military radar or TCAD (i.e. "TCAS lite" systems now being
sold for GA aircraft, not many of these flying yet but it seems quite
a lot of the $400k or so popular GA aircraft get sold with these
systems). I see my transponder being interrogated and my MRX PCAS
working out in the boondocks of the CA/NV great basin, down in valleys
in central CA well away from SSR radar etc. where likely interrogation
sources are airline traffic TCAS.

This topic keeps coming up again and again, and unfortunately r.a.s
seem to be write only, a search of the archives will turn up lots of
dicusssion on PCAS. The bottom line is that PCAS works suprisingly.
But it relies on transponder equipped aircraft so obviously won't work
between gliders that are not transponder equipped. The issue here is
getting your flying buddies to install tranponders not worrying about
wether those tranponders are likely to be painted by radar or TCAS,
etc. they very likely will. Zaon Flight systems keeps trying to
educate people about this, look at the coverage maps at
http://www.zaonflight.com/content/view/22/10/ as a starting point.

The adoption pattern that I've seen for PCAS is one pilot at a glider
port buys one and once people see that it works all of a sudden lots
of pilots have them. I'm not suprised people are pessimistic that
these little toys work, but they do work remarkably well, try to find
somebody in your area who has one and get their feedback on it or even
better borrow it and go flying.

PCAS *is* capable of working at low altitudes including in remote
areas, however I might disagree that the major danger of mid-air
collisions are at "low altitudes". Certainly not the glider-heavy iron
collisions that I am concerned about as a strategic threat to our
sport. And we could argue about what low altitude means, but around
places like Reno, or San Jose airspace where I fly the real danger
points for collisions that I worry about are some victor airways and
associated traffic into and out of VORs and approach/departure routes
or heavy iron, particuary that traffic transitioning down from class A
airspace and very very busy in the cockpit and certainly not
expecting a glider sitting there just below class A... just like the
Minden area Hawker/ASG-29 collision.

BTW Transponders, keep coming up as well on r.a.s, they also work
remarkably well - just ask anybody who flies with a transpoder near
these areas and actually listens to or talks to approach control.
Modern transponders don't have a high drain/exotic battery
requirements (some PDAs/GPSs can be worse), might take a little work
to install, there are really not difficult problems with antenna
location etc. etc. Yes they cost money to buy and install and that can
be a serious barrier -- everything else is addressable or just an
excuse. Once you fly with a transponder in high traffic areas (like
near Reno as JJ said) you suddenly wake up to ATC vectoring heavy iron
around you, being seen by TCAS, etc. a whole scary world many people
are oblivious to. If your shooting patterns miles from anywhere I
don't care if you have a transponder, but if you are flying around,
under or over major airspace then you are taking more of a risk and I
get very worried about the damage to our sport when a glider collides
with a commercial aircraft. (yep my main concern is about protecting
the sport not protecting glider pilots from an individual mid-air,
that's secondary - and on average we are probably more of a danager to
ourselves through stall/spin accidents or lack of pre-flight/positive
control checks than mid-air collisions.).

Darryl Ramm
6DX

Andrew,

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.


Two points:

1. Except at very remote fields, the likelyhood of airliners with TCAS
being above the pattern is high at most busy GA fields, since they will
be near major cities.

2. In a busy pattern, I would not want you to look at a fancy display
giving you traffic information, I want you to look out.

To expand: My experience with these simpler devices is that if you have
more than, say, two close-by targets (a typical situation in a busy
pattern), they become useless since you'll be busy looking outside. I
turn our voice alerting off on the Monroy in these cases, since it will
just say "traffic nearby" all the time and show a distance of a mile. I
know that already, so I look outside.

These units are great for alerting you at times where you don't expect
traffic to be around, e.g. at that lonely field where it finds you that
one other plane in the pattern you have missed, or during cruise when
you are busy programming the GPS.

--
Thomas Borchert (EDDH)

I find it also effective in alerting for glider traffic nearby, if the
glider is transponder equiped and the transponder is on. Now that more
pilots are flying with PCAS it is even more important to keep your
transponder on in remote areas such as the White Mountains.
Transponders are still interogated in these areas and will alert PCAS
equiped gliders to your presence.

Ramy

On Jun 4, 9:38 pm, "
wrote:
On Jun 4, 7:31 pm, Andrew Sarangan wrote:





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.

We don't need to dream about exotic technology, the stuff available
today does the job well enough to be very useful. Wherever you are
flying you are very likely to be being painted by TCAS, civil SSR
radar or military radar or TCAD (i.e. "TCAS lite" systems now being
sold for GA aircraft, not many of these flying yet but it seems quite
a lot of the $400k or so popular GA aircraft get sold with these
systems). I see my transponder being interrogated and my MRX PCAS
working out in the boondocks of the CA/NV great basin, down in valleys
in central CA well away from SSR radar etc. where likely interrogation
sources are airline traffic TCAS.

This topic keeps coming up again and again, and unfortunately r.a.s
seem to be write only, a search of the archives will turn up lots of
dicusssion on PCAS. The bottom line is that PCAS works suprisingly.
But it relies on transponder equipped aircraft so obviously won't work
between gliders that are not transponder equipped. The issue here is
getting your flying buddies to install tranponders not worrying about
wether those tranponders are likely to be painted by radar or TCAS,
etc. they very likely will. Zaon Flight systems keeps trying to
educate people about this, look at the coverage maps athttp://www.zaonflight.com/content/view/22/10/as a starting point.

The adoption pattern that I've seen for PCAS is one pilot at a glider
port buys one and once people see that it works all of a sudden lots
of pilots have them. I'm not suprised people are pessimistic that
these little toys work, but they do work remarkably well, try to find
somebody in your area who has one and get their feedback on it or even
better borrow it and go flying.

PCAS *is* capable of working at low altitudes including in remote
areas, however I might disagree that the major danger of mid-air
collisions are at "low altitudes". Certainly not the glider-heavy iron
collisions that I am concerned about as a strategic threat to our
sport. And we could argue about what low altitude means, but around
places like Reno, or San Jose airspace where I fly the real danger
points for collisions that I worry about are some victor airways and
associated traffic into and out of VORs and approach/departure routes
or heavy iron, particuary that traffic transitioning down from class A
airspace and very very busy in the cockpit and certainly not
expecting a glider sitting there just below class A... just like the
Minden area Hawker/ASG-29 collision.

BTW Transponders, keep coming up as well on r.a.s, they also work
remarkably well - just ask anybody who flies with a transpoder near
these areas and actually listens to or talks to approach control.
Modern transponders don't have a high drain/exotic battery
requirements (some PDAs/GPSs can be worse), might take a little work
to install, there are really not difficult problems with antenna
location etc. etc. Yes they cost money to buy and install and that can
be a serious barrier -- everything else is addressable or just an
excuse. Once you fly with a transponder in high traffic areas (like
near Reno as JJ said) you suddenly wake up to ATC vectoring heavy iron
around you, being seen by TCAS, etc. a whole scary world many people
are oblivious to. If your shooting patterns miles from anywhere I
don't care if you have a transponder, but if you are flying around,
under or over major airspace then you are taking more of a risk and I
get very worried about the damage to our sport when a glider collides
with a commercial aircraft. (yep my main concern is about protecting
the sport not protecting glider pilots from an individual mid-air,
that's secondary - and on average we are probably more of a danager to
ourselves through stall/spin accidents or lack of pre-flight/positive
control checks than mid-air collisions.).

Darryl Ramm
6DX- Hide quoted text -

- Show quoted text -

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