Transponder Praise

[jcarlyle]

On July 2 (a day with blue skies, a few scattered CUs and typical east
coast haze) a friend and I were thermalling our ASW-20 and ASW-19
sailplanes at 6,000 feet 3 miles SE of Blairstown, NJ (a clearly
marked glider port some 40 miles from Newark Airport and Teterboro
Airport). My Zaon MRX alerted us to traffic at our altitude 5 miles
away, which then rapidly closed on us. Despite our best efforts over
the next 30 seconds, neither my friend nor I saw anything approaching.
Then suddenly we saw a business jet in a 45-50 degree bank less than a
mile away. Apparently my transponder caused a TA on his TCAS, he
looked outside and saw our wings flashing, and he turned away from the
impending collision.

I realize not everyone flies in a high traffic area like that around
NY and PHL. But especially for my soaring friends who fly the
Governor’s Cup course, I strongly recommend you put a transponder in
your ship. They cost less than a glide computer, and while they won’t
tell you where you are, a transponder might just get you home someday…

-John

[BT]

Transponders are a good thing.. when the other guy has TCAS or TIS
capability.
I would venture a guess it's 50-50 he never saw you and simply reacted to
the TA commands.
The small GA aircraft without a TIS display will still never see you.
BT


"jcarlyle" > wrote in message
...
On July 2 (a day with blue skies, a few scattered CUs and typical east
coast haze) a friend and I were thermalling our ASW-20 and ASW-19
sailplanes at 6,000 feet 3 miles SE of Blairstown, NJ (a clearly
marked glider port some 40 miles from Newark Airport and Teterboro
Airport). My Zaon MRX alerted us to traffic at our altitude 5 miles
away, which then rapidly closed on us. Despite our best efforts over
the next 30 seconds, neither my friend nor I saw anything approaching.
Then suddenly we saw a business jet in a 45-50 degree bank less than a
mile away. Apparently my transponder caused a TA on his TCAS, he
looked outside and saw our wings flashing, and he turned away from the
impending collision.

I realize not everyone flies in a high traffic area like that around
NY and PHL. But especially for my soaring friends who fly the
Governor’s Cup course, I strongly recommend you put a transponder in
your ship. They cost less than a glide computer, and while they won’t
tell you where you are, a transponder might just get you home someday…

-John

[Darryl Ramm]

On Jul 5, 10:21*am, "BT" > wrote:
> Transponders are a good thing.. when the other guy has TCAS or TIS
> capability.
> I would venture a guess it's 50-50 he never saw you and simply reacted to
> the TA commands.
> The small GA aircraft without a TIS display will still never see you.
> BT
>
> "jcarlyle" > wrote in message
>
> ...
> On July 2 (a day with blue skies, a few scattered CUs and typical east
> coast haze) a friend and I were thermalling our ASW-20 and ASW-19
> sailplanes at 6,000 feet 3 miles SE of Blairstown, NJ (a clearly
> marked glider port some 40 miles from Newark Airport and Teterboro
> Airport). My Zaon MRX alerted us to traffic at our altitude 5 miles
> away, which then rapidly closed on us. Despite our best efforts over
> the next 30 seconds, neither my friend nor I saw anything approaching.
> Then suddenly we saw a business jet in a 45-50 degree bank less than a
> mile away. Apparently my transponder caused a TA on his TCAS, he
> looked outside and saw our wings flashing, and he turned away from the
> impending collision.
>
> I realize not everyone flies in a high traffic area like that around
> NY and PHL. But especially for my soaring friends who fly the
> Governor’s Cup course, I strongly recommend you put a transponder in
> your ship. They cost less than a glide computer, and while they won’t
> tell you where you are, a transponder might just get you home someday…
>
> -John

I hope the real point is that without a transponder you are really are
quite invisible in the system. The GA aircraft has a lot less chance
of avoiding you if you don't have a transponder at all. More and more
GA aircraft are flying with "something", but certainly not TCAS. I
wish numbers were available but look around the airport, certainly the
high performance singles crowd and above seem to have traffic
avoidance toys, including PCAS (e.g Zaon MRX) or more advanced TAS
systems from vendors like Avidyne, or they may have TIS, but that's
getting less interesting nowdays. Or GA aircraft may just be under the
control of ATC or under flight following and get a traffic advisory.
And to counter recent concerns about what ATC does with VFR traffic -
I've had excellent advisories of VFR to VFR traffic when in a
sailplane under flight following (and hear them advisign traffic of
me) - including to unknown VFR (i.e. traffic squawking 1200) and heard
traffic advisories about me to airline traffic when not under flight
following (including Reno approach, before the mid-air).

Darryl

[Hellman]

On Jul 5, 10:21*am, "BT" > wrote:
> Transponders are a good thing.. when the other guy has TCAS or TIS
> capability.
> I would venture a guess it's 50-50 he never saw you and simply reacted to
> the TA commands.
> The small GA aircraft without a TIS display will still never see you.
> BT

Which is why it's good to fly with both a transponder and a PCAS like
the Zaon MRX. I fly near both SFO and RNO airspace, and while these
aids must be regarded as aids - not substitutes - I find them
invaluable for helping "see and be seen." I know there's a cost
involved, but in the grand scheme of the cost of soaring, it is not a
huge increase when amortized over the life of the units.

As I noted in a PASCO Safety Seminar talk last Fall, one way to reduce
fatalities is to treat serious but non-fatal accidents with the same
respect as if there had been loss of life. Along those lines, what our
reaction (and the FAA's!) would have been if the Minden glider-bizjet
midair two years ago had been with an airliner and if there had been
significant loss of life on the airliner. I suspect our use of
transponders and PCAS would go way up, voluntarily at first and then
mandatorily as the FAA got into the act and took away many of our
privileges. Let's not wait for something of that magnitude - which
could kill soaring as we know it along with hundreds of people - to
take action.

I wrote up that talk "Complacency: What Me Worry?" and have posted it
at

http://www-ee.stanford.edu/~hellman/soaring/PASCO_2007_talk.html

Martin

[BT]

Agree to all Darryl..
Sadly my club LS4 is without a transponder

But I have listened to ATC and heard them calling traffic, "altitude unknown
appears to be a glider", so they know we are there.
The problem lies with the smaller GA aircraft ducking in under the edge of
Class B so as to not have to talk to approach control while they zip into
one of the satellite airports.

BT

[5Z]

Last Tuesday, I received a package with my transponder in it. Of
course, the soaring weather looked good on Friday and Saturday,
perhaps Sunday, so the installation would have to wait another week.

Today, as I prepare to take off, my MRX fails to turn on. I launch
anyway.

Our airport is located half way between Colorado Springs and Denver.
Lots of airliners, etc. flying overhead at 9-13K MSL (2-5K AGL).

About 45 minutes after launch, I watch a TED 737 cruise less than 1/4
mile abeam my thermal. Later, as I'm getting the last bit of altitude
about 5 E of COS, a Southwest 737 drives right through the center of
my thermal and 500' below. I think all the virga and OD around were
squeezing gliders and airliners into a fairly small area. After the
Southwest jet flew under me, I called COS approach and stayed in
contact for the next 15 miles. They NEVER saw my primary target
(ASH-26E) even though I was able to provide a very accurate position.

What's interesting is that in both cases, I was thermalling, so
providing about the best possible "target" for a visual observation.

Guess what I'll be doing tomorrow!

-Tom

PS Our club just bought 3 MRX units to put in the club ships in order
to provide more info to the pilots. And yes, we are in contact with
both DEN and COS approach regarding the traffic issues.

[Soarin Again[_2_]]

At 16:34 05 July 2008, jcarlyle wrote:
> My Zaon MRX alerted us to traffic at our altitude 5 miles
>away, which then rapidly closed on us. Despite our best
>efforts over the next 30 seconds, neither my friend nor
>I saw anything approaching.
>Then suddenly we saw a business jet in a 45-50 degree
>bank less than a mile away. Apparently my transponder
>caused a TA on his TCAS, he looked outside and saw our
>wings flashing, and he turned away from the impending collision.

Assuming that you are talking nautical miles. If you are alerted
to the aircraft at 5 miles and within 30 seconds he is at 1 mile
then is apparently doing 480 knots (well above the 250 kt limit
below 10,000 msl).
If you don't see him and you know he is at your altitude and
closing at that high of a rate, why not just pull full spoilers and
dive to vacate that altitude as quickly as possible?
Is there a better option available?

[Darryl Ramm]

On Jul 5, 11:27*pm, Soarin Again > wrote:
> At 16:34 05 July 2008, jcarlyle wrote:
>
> > My Zaon MRX alerted us to traffic at our altitude 5 miles
> >away, which then rapidly closed on us. Despite our best
> >efforts over the next 30 seconds, neither my friend nor
> >I saw anything approaching.
> >Then suddenly we saw a business jet in a 45-50 degree
> >bank less than a mile away. Apparently my transponder
> >caused a TA on his TCAS, he looked outside and saw our
> >wings flashing, and he turned away from the impending collision.
>
> Assuming that you are talking nautical miles. *If you are alerted
> to the aircraft at 5 miles and within 30 seconds he is at 1 mile
> then is apparently doing 480 knots (well above the 250 kt limit
> below 10,000 msl).
> If you don't see him and you know he is at your altitude and
> closing at that high of a rate, why not just pull full spoilers and
> dive to vacate that altitude as quickly as possible?
> Is there a better option available?

The distance measurements with PCAS are approximate and only based on
radiated power from the other aircraft's transponder and can be fooled
as the aircraft change atitudes/altirudes relateive to each other.

With two gliders flying near each other and both thermalling (so that
you are most visible to other traffic) I'd be trying to stay with the
other glider (traffic might see and try to avoid one glider and hit
the other), I'd be focused on scanning for the traffic and not be
shoving the nose over and pulling spoilers unless I could see the
traffic and thought that was a good thign to do. If traffic is
getting close on PCAS and I can't see it I will bank or turn the
glider to have a good look around.


Darryl

[JS]

Six or seven years ago, I started to fly out of Jean, Nevada fairly
often so I installed a transponder. Jean is just outside the Las Vegas
Class B (8 to 9,000' at 20NM), and under the Mode C Veil which - not
printed on charts - is essentially Class B between 9 and 10,000'
unless you have a transponder or use a negotiated climb window.
One weekday morning, the pilot for the skydiving operation helped me
rig. That evening he helped me put the glider back in the box.
As we were pulling tape, he said: "You have a transponder, don't you?
I heard ATC vectoring aircraft around you." The pilot must actually
talk with control before a jump run to allow several small objects to
drop through the veil.
That confirmed the good idea of installing the transponder and
batteries.
Just installed and certified a transponder in the new flying
machine, too. But this is old technology. When we all have
transponders it will drive ATC crazy with gaggles of proximity alarms
going off. Be better if every aircraft had FLARM.
Jim

[Eric Greenwell]

JS wrote:

> Just installed and certified a transponder in the new flying
> machine, too. But this is old technology. When we all have
> transponders it will drive ATC crazy with gaggles of proximity alarms
> going off.

That can be handled with an assigned code like the 0440 used in Reno for
gliders. The software can be instructed to ignore conflicts between 0440
codes, which, I believe, is what is done in Reno. There may be other
methods they can already use, especially if the glider density is lower
than Reno.

> Be better if every aircraft had FLARM.

We will, in 10 to 20 years, but we'll likely call it ADSB. FLARM, as
presently implemented, probably wouldn't appeal to 250+ knot airliners,
because it's range is too small. I think it's better to work for a low
cost, low power, ADSB with modest features like the Mitre unit.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[Andy[_1_]]

On Jul 5, 10:21*am, "BT" > wrote:
> Transponders are a good thing.. when the other guy has TCAS or TIS
> capability.
> I would venture a guess it's 50-50 he never saw you and simply reacted to
> the TA commands.

TCAS never commands an aircraft to turn to avoid a conflict. TCAS is
only capable of providing vertical commands. If the aircraft turned
it's reasonable to assume the pilots had visual contact.

Andy

[Mike Schumann]

We may not have to wait 10-20 years. The new MITRE low cost ADS-B
transceiver (transmitting your location, while also receiving traffic &
weather data) should be in testing this fall. The last I heard, they
already have a couple of companies lined up to license the design for
commercial production.

Mike Schumann

"Eric Greenwell" > wrote in message
news:Bj9ck.310$rb1.279@trndny08...
> JS wrote:
>
>> Just installed and certified a transponder in the new flying
>> machine, too. But this is old technology. When we all have
>> transponders it will drive ATC crazy with gaggles of proximity alarms
>> going off.
>
> That can be handled with an assigned code like the 0440 used in Reno for
> gliders. The software can be instructed to ignore conflicts between 0440
> codes, which, I believe, is what is done in Reno. There may be other
> methods they can already use, especially if the glider density is lower
> than Reno.
>
>> Be better if every aircraft had FLARM.
>
> We will, in 10 to 20 years, but we'll likely call it ADSB. FLARM, as
> presently implemented, probably wouldn't appeal to 250+ knot airliners,
> because it's range is too small. I think it's better to work for a low
> cost, low power, ADSB with modest features like the Mitre unit.
>
> --
> Eric Greenwell - Washington State, USA
> * Change "netto" to "net" to email me directly
>
> * Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
> * New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more
>
> * "A Guide to Self-launching Sailplane Operation" at www.motorglider.org


** Posted from http://www.teranews.com **

[BT]

True.. the most basic levels of TCAS do not give commands..
those aboard most airliners do
BT


"Andy" > wrote in message
...
On Jul 5, 10:21 am, "BT" > wrote:
> Transponders are a good thing.. when the other guy has TCAS or TIS
> capability.
> I would venture a guess it's 50-50 he never saw you and simply reacted to
> the TA commands.

TCAS never commands an aircraft to turn to avoid a conflict. TCAS is
only capable of providing vertical commands. If the aircraft turned
it's reasonable to assume the pilots had visual contact.

Andy

[BT]

the system will not give alarms for multiple 1200 codes in the same vicinity
that might conflict with each other
it will give an alarm for a discreet code conflicting with another discrete
code.. (0440 is not considered discrete)
It may or may not give alarms if a discrete code will conflict with a 1200
code

The jumpers at Jean have negotiated 1201, 1202, 1203 etc so TRACON instantly
knows it's the jump plane.

BT

"Eric Greenwell" > wrote in message
news:Bj9ck.310$rb1.279@trndny08...
> JS wrote:
>
>> Just installed and certified a transponder in the new flying
>> machine, too. But this is old technology. When we all have
>> transponders it will drive ATC crazy with gaggles of proximity alarms
>> going off.
>
> That can be handled with an assigned code like the 0440 used in Reno for
> gliders. The software can be instructed to ignore conflicts between 0440
> codes, which, I believe, is what is done in Reno. There may be other
> methods they can already use, especially if the glider density is lower
> than Reno.
>
>> Be better if every aircraft had FLARM.
>
> We will, in 10 to 20 years, but we'll likely call it ADSB. FLARM, as
> presently implemented, probably wouldn't appeal to 250+ knot airliners,
> because it's range is too small. I think it's better to work for a low
> cost, low power, ADSB with modest features like the Mitre unit.
>
> --
> Eric Greenwell - Washington State, USA
> * Change "netto" to "net" to email me directly
>
> * Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
> * New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more
>
> * "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[Darryl Ramm]

On Jul 6, 7:57*pm, "BT" > wrote:
> True.. the most basic levels of TCAS do not give commands..
> those aboard most airliners do
> BT
>
> "Andy" > wrote in message
>
> ...
> On Jul 5, 10:21 am, "BT" > wrote:
>
> > Transponders are a good thing.. when the other guy has TCAS or TIS
> > capability.
> > I would venture a guess it's 50-50 he never saw you and simply reacted to
> > the TA commands.
>
> TCAS never commands an aircraft to turn to avoid a conflict. TCAS is
> only capable of providing vertical commands. *If the aircraft turned
> it's reasonable to assume the pilots had visual contact.
>
> Andy

No! Andy was exactly correct, even TCAS-II resolution advisories (RA)
are vertical only. You need a time machine and TCAS IV for lateral
advisories. And strictly going back to earlier comments the traffic
advisory (TA) does not issue a resolution, that is the RA.

Still TCAS, if they were so equipped, could have indicated to the
pilot(s) the presence of the transponder equipped gliders which was
the initial point. But who knows, maybe ATC issues a traffic advisory?

Darryl

[jcarlyle]

What is the group’s suggestion on the best procedure to follow when
flying a transponder equipped sailplane outside of an area where
specific squawk codes have been assigned, ie, where you get lumped in
with other VFR traffic? It’d be nice if gliders and balloons had a
discrete squawk code everywhere in the US, so ATC would know
immediately that we were a different kind of traffic, but since that’s
not going to happen soon (if ever) what strategies could glider pilots
use to stay as safe as possible?

Currently I’m squawking 1200, communicating on 123.3 with other XC
gliders, monitoring my Zaon MRX PCAS for transponder equipped traffic,
and of course constantly visually scanning for traffic. As Darryl
said, if my PCAS alerts me to closing traffic and I don’t see it, I
start turning while increasing my visual scan. This makes me more
visible to them, and allows me to look at what was my 6 o’clock. I
also tend to get more vigilant when I’m nearing a VOR as well as when
I'm flying at a multiple of 1000 feet, as I figure other traffic tends
to fly at those locations and altitudes.

One hardware change I plan on making soon is to move my PCAS antenna
from the instrument panel area to a location back in the tail boom. My
PCAS antenna is now getting shadowed from multiple directions by
various instruments from the rear and below, by the compass from the
front and above, by the canopy and instrument panel lifting mechanism
from the front, and by the rudder pedal assembly from the front and
below. In the tail boom the only real shadowing will come from the
landing gear from the front. Shadowing of the PCAS antenna in its
present location might explain why the business jet closed with my
friend and I so quickly.

-John

On Jul 6, 3:36 am, Darryl Ramm > wrote:
> The distance measurements with PCAS are approximate and only based on
> radiated power from the other aircraft's transponder and can be fooled
> as the aircraft change atitudes/altirudes relateive to each other.
>
> With two gliders flying near each other and both thermalling (so that
> you are most visible to other traffic) I'd be trying to stay with the
> other glider (traffic might see and try to avoid one glider and hit
> the other), I'd be focused on scanning for the traffic and not be
> shoving the nose over and pulling spoilers unless I could see the
> traffic and thought that was a good thign to do. If traffic is
> getting close on PCAS and I can't see it I will bank or turn the
> glider to have a good look around.
>
> Darryl

[Papa3]

On Jul 5, 12:34*pm, jcarlyle > wrote:
> On July 2 (a day with blue skies, a few scattered CUs and typical east
> coast haze) a friend and I were thermalling our ASW-20 and ASW-19
> sailplanes at 6,000 feet 3 miles SE of Blairstown, NJ (a clearly
> marked glider port some 40 miles from Newark Airport and Teterboro
> Airport). My Zaon MRX alerted us to traffic at our altitude 5 miles
> away, which then rapidly closed on us. Despite our best efforts over
> the next 30 seconds, neither my friend nor I saw anything approaching.
> Then suddenly we saw a business jet in a 45-50 degree bank less than a
> mile away. Apparently my transponder caused a TA on his TCAS, he
> looked outside and saw our wings flashing, and he turned away from the
> impending collision.
>
> I realize not everyone flies in a high traffic area like that around
> NY and PHL. But especially for my soaring friends who fly the
> Governor’s Cup course, I strongly recommend you put a transponder in
> your ship. They cost less than a glide computer, and while they won’t
> tell you where you are, a transponder might just get you home someday…
>
> -John

What I particularly like about John's post is that it's a "total
package" approach. No one item is enough, and even all of them
combined aren't foolproof.

As an aside, any of us who fly on the perimeter of busy class B
airspace need to take the time to understand the standard terminal
arrival routes. Spend some time learning where the "big boys" are
and make a conscious decision not to go there. For instance, there
are 3 or 4 places in our local contest area (Governor's Cup) where I
would never want to be even if the best thermal in the world is
sitting right there.

As a second aside, I came as close as I've ever come to being skewered
by a Dash-8 a couple of weeks ago at 5,000 feet in a spot that's not
on anyone's "standard" anything. Who knows if the guy was being
vectored for spacing or whatever, but it was REAL close. "Get the
transponder installed" has been on the to-do list for the winter. I
think it's going to make it to the "must do" list for the next month
or so.

P3

[Mike Schumann]

One option would be to take along a handheld and use it request flight
following from your local center.

Mike Schuman

"jcarlyle" > wrote in message
...
What is the group’s suggestion on the best procedure to follow when
flying a transponder equipped sailplane outside of an area where
specific squawk codes have been assigned, ie, where you get lumped in
with other VFR traffic? It’d be nice if gliders and balloons had a
discrete squawk code everywhere in the US, so ATC would know
immediately that we were a different kind of traffic, but since that’s
not going to happen soon (if ever) what strategies could glider pilots
use to stay as safe as possible?

Currently I’m squawking 1200, communicating on 123.3 with other XC
gliders, monitoring my Zaon MRX PCAS for transponder equipped traffic,
and of course constantly visually scanning for traffic. As Darryl
said, if my PCAS alerts me to closing traffic and I don’t see it, I
start turning while increasing my visual scan. This makes me more
visible to them, and allows me to look at what was my 6 o’clock. I
also tend to get more vigilant when I’m nearing a VOR as well as when
I'm flying at a multiple of 1000 feet, as I figure other traffic tends
to fly at those locations and altitudes.

One hardware change I plan on making soon is to move my PCAS antenna
from the instrument panel area to a location back in the tail boom. My
PCAS antenna is now getting shadowed from multiple directions by
various instruments from the rear and below, by the compass from the
front and above, by the canopy and instrument panel lifting mechanism
from the front, and by the rudder pedal assembly from the front and
below. In the tail boom the only real shadowing will come from the
landing gear from the front. Shadowing of the PCAS antenna in its
present location might explain why the business jet closed with my
friend and I so quickly.

-John

On Jul 6, 3:36 am, Darryl Ramm > wrote:
> The distance measurements with PCAS are approximate and only based on
> radiated power from the other aircraft's transponder and can be fooled
> as the aircraft change atitudes/altirudes relateive to each other.
>
> With two gliders flying near each other and both thermalling (so that
> you are most visible to other traffic) I'd be trying to stay with the
> other glider (traffic might see and try to avoid one glider and hit
> the other), I'd be focused on scanning for the traffic and not be
> shoving the nose over and pulling spoilers unless I could see the
> traffic and thought that was a good thign to do. If traffic is
> getting close on PCAS and I can't see it I will bank or turn the
> glider to have a good look around.
>
> Darryl


** Posted from http://www.teranews.com **

[Eric Greenwell]

jcarlyle wrote:

> One hardware change I plan on making soon is to move my PCAS antenna
> from the instrument panel area to a location back in the tail boom. My
> PCAS antenna is now getting shadowed from multiple directions by
> various instruments from the rear and below, by the compass from the
> front and above, by the canopy and instrument panel lifting mechanism
> from the front, and by the rudder pedal assembly from the front and
> below. In the tail boom the only real shadowing will come from the
> landing gear from the front. Shadowing of the PCAS antenna in its
> present location might explain why the business jet closed with my
> friend and I so quickly.

Shadowing is certainly a possibility. I've also wondered if the amount
of radar interrogations can cause the same thing; e.g., where I fly in
SE Washington state, my transponder is triggered only 5-10 times a minute.

Rather than just relocating the antenna, you can get Zaon's dual antenna
option. That puts antennas top and bottom on the aircraft, essentially
eliminating all shadowing. It might be easier than moving one antenna to
the tail, but it's pricey at $280 for the option, plus two blade antennas.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[chipsoars]

On Jul 7, 1:29*pm, Papa3 > wrote:
> On Jul 5, 12:34*pm, jcarlyle > wrote:
>
>
>
>
>
> > On July 2 (a day with blue skies, a few scattered CUs and typical east
> > coast haze) a friend and I were thermalling our ASW-20 and ASW-19
> > sailplanes at 6,000 feet 3 miles SE of Blairstown, NJ (a clearly
> > marked glider port some 40 miles from Newark Airport and Teterboro
> > Airport). My Zaon MRX alerted us to traffic at our altitude 5 miles
> > away, which then rapidly closed on us. Despite our best efforts over
> > the next 30 seconds, neither my friend nor I saw anything approaching.
> > Then suddenly we saw a business jet in a 45-50 degree bank less than a
> > mile away. Apparently my transponder caused a TA on his TCAS, he
> > looked outside and saw our wings flashing, and he turned away from the
> > impending collision.
>
> > I realize not everyone flies in a high traffic area like that around
> > NY and PHL. But especially for my soaring friends who fly the
> > Governor’s Cup course, I strongly recommend you put a transponder in
> > your ship. They cost less than a glide computer, and while they won’t
> > tell you where you are, a transponder might just get you home someday…
>
> > -John
>
> What I particularly like about John's post is that it's a "total
> package" approach. * *No one item is enough, and even all of them
> combined aren't foolproof.
>
> As an aside, any of us who fly on the perimeter of busy class B
> airspace need to take the time to understand the standard terminal
> arrival routes. * *Spend some time learning where the "big boys" are
> and make a conscious decision not to go there. * For instance, there
> are 3 or 4 places in our local contest area (Governor's Cup) where I
> would never want to be even if the best thermal in the world is
> sitting right there.
>
> As a second aside, I came as close as I've ever come to being skewered
> by a Dash-8 a couple of weeks ago at 5,000 feet in a spot that's not
> on anyone's "standard" anything. * Who knows if the guy was being
> vectored for spacing or whatever, but it was REAL close. * *"Get the
> transponder installed" has been on the to-do list for the winter. * I
> think it's going to make it to the "must do" list for the next month
> or so.
>
> P3- Hide quoted text -
>
> - Show quoted text -

What led to our transponder installation was my nearly getting run
over from the 6 by a Regional Jet near UKT about a year ago,
in an area where I've never seen commercial activity. It may an
exageration, but I think the separation was less than 1000'. Hard to
see and avoid that.

Needless to say, that I was gratified to watch a Dash 8 manueuver to
avoid me
in a thermal near Limerick a couple of weeks ago. I think the Zaon is
the next addition, or is it the ELT upgrade............

Interestingly, these devices have a much higher WAF (wife acceptance
factor) than normal glider related stuff. In fact, the transponder
was mandated.

Chip F.

[Mike125]

While not a really close call, I had my eyes opened last week, too.
Our airport is located between PHL and ACY (Class C) and Maguire AFB.
The heavies are rarely a problem but there is also an airway that
runs adjacent to the field and I try to keep extra vigilant when near
it. (I don't have a transponder). I was thermalling near the airway at
about 4000' when I saw four dots under a line at my altitude and they
appeared to be heading right at me. I moved away and watched a 747 go
by at a distance close enough to see that, while painted, it had no
logos showing anywhere. He wasn't heading toward PHL or ACY and didn't
appear to be climbing or descending and wasn't on the airway. He
wasn't flying in the "normal" places and I doubt he saw me. A few more
turns in the thermal w/o seeing him would have made things very
interesting. I think its time to invest in some electronic
insurance.

Mike

[jcarlyle]

P3, learning where the "big boys" are is something I've just gotten
involved with. I persuaded a FedEx pilot to educate me about approach
charts, and using that information I've modified my SUA file to mark
VORs and PHL approach fixes in and near the lower part of the southern
Governor's Cup route. I'll contact you off line - I'd be glad to share
and would like to learn from you the 3 or 4 places you would never
want to be on the GC route.

-John

On Jul 7, 1:29 pm, Papa3 > wrote:
> What I particularly like about John's post is that it's a "total
> package" approach. No one item is enough, and even all of them
> combined aren't foolproof.
>
> As an aside, any of us who fly on the perimeter of busy class B
> airspace need to take the time to understand the standard terminal
> arrival routes. Spend some time learning where the "big boys" are
> and make a conscious decision not to go there. For instance, there
> are 3 or 4 places in our local contest area (Governor's Cup) where I
> would never want to be even if the best thermal in the world is
> sitting right there.
>
> As a second aside, I came as close as I've ever come to being skewered
> by a Dash-8 a couple of weeks ago at 5,000 feet in a spot that's not
> on anyone's "standard" anything. Who knows if the guy was being
> vectored for spacing or whatever, but it was REAL close. "Get the
> transponder installed" has been on the to-do list for the winter. I
> think it's going to make it to the "must do" list for the next month
> or so.
>
> P3

[jcarlyle]

Eric, I wasn't too impressed with the antenna extenders that Zaon
offers. They use RG-174 cable, and while it's OK for short runs it
would markedly decrease the signal strength running from my tail cone
to my instrument panel. I've found several places on line that offer 6
meter male to female RP SMA cables made from LMR 200 for less than
$15. The attenuation with LMR 200 at 1 GHz is 10 dB per 100 feet,
rather than the 22 dB per 100 feet with RG-174.

I guess there's a possibility that high interrogation rates could mess
up the Zaon range estimate, but even here in the PHL NY area the
transponder's transmitting triangle only flashes about once a second.
Could be that there are many, many transmissions per flash, but I've
noticed that generally if the Zaon says the range is within 3 miles of
me it is pretty accurate (to my "calibrated" eye, that is).

-John

On Jul 7, 2:39 pm, Eric Greenwell > wrote:
> Shadowing is certainly a possibility. I've also wondered if the amount
> of radar interrogations can cause the same thing; e.g., where I fly in
> SE Washington state, my transponder is triggered only 5-10 times a minute.
>
> Rather than just relocating the antenna, you can get Zaon's dual antenna
> option. That puts antennas top and bottom on the aircraft, essentially
> eliminating all shadowing. It might be easier than moving one antenna to
> the tail, but it's pricey at $280 for the option, plus two blade antennas.
>
> --
> Eric Greenwell - Washington State, USA

[Eric Greenwell]

jcarlyle wrote:
> Eric, I wasn't too impressed with the antenna extenders that Zaon
> offers. They use RG-174 cable, and while it's OK for short runs it
> would markedly decrease the signal strength running from my tail cone
> to my instrument panel. I've found several places on line that offer 6
> meter male to female RP SMA cables made from LMR 200 for less than
> $15. The attenuation with LMR 200 at 1 GHz is 10 dB per 100 feet,
> rather than the 22 dB per 100 feet with RG-174.

The PCAS MRX Dual Antenna Harness isn't really an "extender", but a way
of improving coverage to eliminate blind spots. I believe the antennas
used with the extender could be mounted close to the cockpit: e.g., one
on top of the glare shield, and one below it on the outside of the
glider (you couldn't do that on a glider that uses a CG hook to tow
with, of course).

Those locations would allow very short cables, if you wanted to;
however, the fact that two antennas are used probably makes up for
losses in the cable. If my math is right, the 15 foot cables they supply
do cut the signal from each antenna by one half, so that suggests they
intend the total signal (both antennas) to be the same as the one
antenna mounted directly on the unit. In any case, the dual antenna
package and the PCAS MRX Single Antenna Harness include "gain adapters",
so perhaps concerns about signal loss are irrelevant.

I suggest calling tech support at Zaon about the cable to use for a
remote mounting. Proper operation might require these losses, which
could be accounted for by the gain adapter.

>
> I guess there's a possibility that high interrogation rates could mess
> up the Zaon range estimate, but even here in the PHL NY area the
> transponder's transmitting triangle only flashes about once a second.
> Could be that there are many, many transmissions per flash, but I've
> noticed that generally if the Zaon says the range is within 3 miles of
> me it is pretty accurate (to my "calibrated" eye, that is).

Actually, I was thinking infrequent interrogations might be the problem,
but it was just a guess.

--
Eric Greenwell - Washington State, USA
* Change "netto" to "net" to email me directly

* Updated! "Transponders in Sailplanes" http://tinyurl.com/y739x4
* New Jan '08 - sections on Mode S, TPAS, ADS-B, Flarm, more

* "A Guide to Self-launching Sailplane Operation" at www.motorglider.org

[jcarlyle]

You're absolutely correct on the heights! Since most of my close calls
have come from IFR traffic, though, I tend to become more antsy at
multiples of 1000. Doesn't mean I let down my guard at other
altitudes...

-John

On Jul 7, 11:31 pm, Clark > wrote:
> Keeping a sharp eye out around VOR's is good. Avoiding VOR's is probably
> better. Still a lot of traffic without GPS out there.
>
> Assuming you're in the USA: IFR traffic will be on the 1000's, VFR will be on
> the 500's. Within 3000 AGL all bets are off.