New transponder mode S vs. mode C

AH, but the real question is... would a 302 or other GPS be capable of
generating the data that could be fed to a Mode S transponder? Yeah,
yeah all the illegal stuff and your insurance would never pay if you
ground looped..., but would it work or are the certified GPS units
sending out a different data protocol?

hans wrote:
Hi Tom!

your 302 does not qualify as a certified GPS for the mode S transponder.

Best Regards


Hans


Tom N. schrieb:

I live in San Antonio, Texas, USA. We fly out of a field 15 nautical
miles away from San Antonio International airport and are basically on
final approach for a lot of jet traffic. There are also two Air Force
bases in the immediate area. There is no requirement in the U.S. to
have mode S as there will be in Europe. However, if there is less
power consumption due to fewer interrogations or if there is more
accuracy on TCAS, I would be willing to go with it. I use a Cambridge
302 for GPS.
Stefan wrote:

Tom N. schrieb:

Any opinions? I plan to install a new Becker transponder in my ASW-28.
Should I go with the old mode C unit or pay extra for the new mode S
unit? Thanks.

Tor answer this question, it would be extremely helpful to know in which
part of the world you intend to fly.

I can't remember any requirement of NMEA output for aviation certified
GPS receiver. Mode S transponder are at least required to work with
ARINC input. I have to check whether the ARINC input is the only
permitted input to the mode S transponder.


Gary Emerson schrieb:
AH, but the real question is... would a 302 or other GPS be capable of
generating the data that could be fed to a Mode S transponder? Yeah,
yeah all the illegal stuff and your insurance would never pay if you
ground looped..., but would it work or are the certified GPS units
sending out a different data protocol?

hans wrote:
Hi Tom!

your 302 does not qualify as a certified GPS for the mode S transponder.

Best Regards


Hans


Tom N. schrieb:

I live in San Antonio, Texas, USA. We fly out of a field 15 nautical
miles away from San Antonio International airport and are basically on
final approach for a lot of jet traffic. There are also two Air Force
bases in the immediate area. There is no requirement in the U.S. to
have mode S as there will be in Europe. However, if there is less
power consumption due to fewer interrogations or if there is more
accuracy on TCAS, I would be willing to go with it. I use a Cambridge
302 for GPS.
Stefan wrote:

Tom N. schrieb:

Any opinions? I plan to install a new Becker transponder in my
ASW-28.
Should I go with the old mode C unit or pay extra for the new mode S
unit? Thanks.

Tor answer this question, it would be extremely helpful to know in
which
part of the world you intend to fly.

Why would you want a Mode S transponder to be fed by a GPS? The
Extended Squitter variation of ADS-B does layer on top of the Mode S
downlink protocol, but simply feeding GPS data to a Mode S transponder
will not make it ADS-B compliant. An entirely new box will be needed.

The only reason to use a Mode S transponder in the US (outside of the
categories of aircraft for which it is mandated) is to take advantage of
the uplinked traffic and weather information, which needs an expensive
and power hungry multi-function display. Since some of those services
are now being shut down in anticipation of ADS-B deployment, even that
reason is slowly being rendered meaningless. Also, do not forget that
it costs roughly twice as much to recertify a Mode S transponder, and
you may have to go farther to find a shop that has the right test equipment.

In response to the original poster, if you spend extra money to install
and maintain a Mode S (instead of C) transponder in a glider operating
in the US, you're simply wasting money...

Marc

Gary Emerson wrote:
AH, but the real question is... would a 302 or other GPS be capable of
generating the data that could be fed to a Mode S transponder? Yeah,
yeah all the illegal stuff and your insurance would never pay if you
ground looped..., but would it work or are the certified GPS units
sending out a different data protocol?

hans wrote:
Hi Tom!

your 302 does not qualify as a certified GPS for the mode S transponder.

Best Regards


Hans


Tom N. schrieb:

I live in San Antonio, Texas, USA. We fly out of a field 15 nautical
miles away from San Antonio International airport and are basically on
final approach for a lot of jet traffic. There are also two Air Force
bases in the immediate area. There is no requirement in the U.S. to
have mode S as there will be in Europe. However, if there is less
power consumption due to fewer interrogations or if there is more
accuracy on TCAS, I would be willing to go with it. I use a Cambridge
302 for GPS.
Stefan wrote:

Tom N. schrieb:

Any opinions? I plan to install a new Becker transponder in my
ASW-28.
Should I go with the old mode C unit or pay extra for the new mode S
unit? Thanks.

Tor answer this question, it would be extremely helpful to know in
which
part of the world you intend to fly.

A Mode S transponder does not need any inputs from a GPS.

Mike Schumann

"Gary Emerson" wrote in message
t...
AH, but the real question is... would a 302 or other GPS be capable of
generating the data that could be fed to a Mode S transponder? Yeah, yeah
all the illegal stuff and your insurance would never pay if you ground
looped..., but would it work or are the certified GPS units sending out
a different data protocol?

hans wrote:
Hi Tom!

your 302 does not qualify as a certified GPS for the mode S transponder.

Best Regards


Hans


Tom N. schrieb:

I live in San Antonio, Texas, USA. We fly out of a field 15 nautical
miles away from San Antonio International airport and are basically on
final approach for a lot of jet traffic. There are also two Air Force
bases in the immediate area. There is no requirement in the U.S. to
have mode S as there will be in Europe. However, if there is less
power consumption due to fewer interrogations or if there is more
accuracy on TCAS, I would be willing to go with it. I use a Cambridge
302 for GPS.
Stefan wrote:

Tom N. schrieb:

Any opinions? I plan to install a new Becker transponder in my
ASW-28.
Should I go with the old mode C unit or pay extra for the new mode S
unit? Thanks.

Tor answer this question, it would be extremely helpful to know in
which
part of the world you intend to fly.

US military fighter type aircraft do not currently have TCAS
Do not rely on TCAS to keep you safe
BT

"Tom N." wrote in message
ups.com...
I live in San Antonio, Texas, USA. We fly out of a field 15 nautical
miles away from San Antonio International airport and are basically on
final approach for a lot of jet traffic. There are also two Air Force
bases in the immediate area. There is no requirement in the U.S. to
have mode S as there will be in Europe. However, if there is less
power consumption due to fewer interrogations or if there is more
accuracy on TCAS, I would be willing to go with it. I use a Cambridge
302 for GPS.
Stefan wrote:
Tom N. schrieb:
Any opinions? I plan to install a new Becker transponder in my ASW-28.
Should I go with the old mode C unit or pay extra for the new mode S
unit? Thanks.

Tor answer this question, it would be extremely helpful to know in which
part of the world you intend to fly.

BT wrote:
US military fighter type aircraft do not currently have TCAS
Do not rely on TCAS to keep you safe

This is correct. However, there is no doubt a TCAS will keep you safeR!
But then again, you must have a transponder to be see on their screen.
It's an overkill on a 2-33 going around the pattern all day long, but
certainly not in a modern glider within 30 miles of a class B or C
airspace.

I fly for the same company involved in the mid-air. Trust me, at the
speed we fly, gliders are hard to see. Heck, even thermalling in a
glider, other gliders can be hard to spot!

Richard
Phoenix AZ

"jeplane" wrote in message
ups.com...
BT wrote:
US military fighter type aircraft do not currently have TCAS
Do not rely on TCAS to keep you safe

This is correct. However, there is no doubt a TCAS will keep you safeR!
But then again, you must have a transponder to be see on their screen.
It's an overkill on a 2-33 going around the pattern all day long, but
certainly not in a modern glider within 30 miles of a class B or C
airspace.

I fly for the same company involved in the mid-air. Trust me, at the
speed we fly, gliders are hard to see. Heck, even thermalling in a
glider, other gliders can be hard to spot!

Richard
Phoenix AZ


I will agree on the safeR part.. but only from part of the variety of
aircraft flying.
Gliders are hard to see.. so are T-38s coming at you nose on. T-38s don't
have TCAS.

Would it have made a difference if it was a Cessna Single Engine at cruise
altitude instead of a glider? Probabily not.. there still may have been an
accident.. granted the Cessna Single would more likely have a transponder,
so the BIZ Jet would have gotten a TCAS return.. but that Cessna with no TIS
display would never have gotten a return on the Jet or the Glider.

I do fly 2-33s inside the Mode C Veil and up to 12K MSL in summer.. and
other gliders much higher. Not just around the traffic pattern. The 2-33,
Grob 103 and LS-4 all show up on approach radar with no transponder.
Center's tend to filter non transponder returns to reduce clutter.

BT