Transponder Inspection Not Required?

In the east (i.e., where we're generally below 10,000 ft.), if a
glider is not flying in Class A, B, or C airspace, does a transponder
fall under the 24-month inspection rule? From the latest AOPA email
advisory (emphasis added):

****************
Question: I know an altimeter inspection is only required when flying
under IFR, but what about the transponder inspection? Is it required
for both VFR and IFR flights?

Answer: Unlike the altimeter inspection that is required to operate
under IFR, A TRANSPONDER INSPECTION IS DICTATED BY THE AIRSPACE
THROUGH WHICH YOU ARE. A transponder used in airspace specified by FAR
91.215 (which includes operation within Class A, within or above Class
B and C, and above 10,000 ft msl) must be inspected within the
preceding 24 calendar months for both VFR and IFR flights. For more
information, view the AOPA online subject report on Aircraft
Inspections.
****************

I checked the cited FAR (and the others it references) and I'm still
not sure of the answer. Ignoring the safety issues of flying around
with a transponder that may not be reporting accurate info, this is
serious question in an area I know relatively little about but which a
lot of us are considering these days.

Chip Bearden
ASW 24 "JB"
USA

This brings up another question and complication regarding the
installation of transponders in sailplanes. The altimeter. I get a
different answer everytime I ask it, but the transponder inspection
may/may not include inspection of the altimeter. I had to install an
IFR altimeter (large size) to pass the original installation
inspection. I could not find a small size altimeter that met the
accuracy requirements. Subsequent inspectors didn't care so I went
back to my small altimeter.

Guy Acheson "DDS"

On May 2, 8:28*am, Chip Bearden wrote:
In the east (i.e., where we're generally below 10,000 ft.), if a
glider is not flying in Class A, B, or C airspace, does a transponder
fall under the 24-month inspection rule? From the latest AOPA email
advisory (emphasis added):

****************
Question: I know an altimeter inspection is only required when flying
under IFR, but what about the transponder inspection? Is it required
for both VFR and IFR flights?

Answer: Unlike the altimeter inspection that is required to operate
under IFR, A TRANSPONDER INSPECTION IS DICTATED BY THE AIRSPACE
THROUGH WHICH YOU ARE. A transponder used in airspace specified by FAR
91.215 (which includes operation within Class A, within or above Class
B and C, and above 10,000 ft msl) must be inspected within the
preceding 24 calendar months for both VFR and IFR flights. For more
information, view the AOPA online subject report on Aircraft
Inspections.
****************

I checked the cited FAR (and the others it references) and I'm still
not sure of the answer. Ignoring the safety issues of flying around
with a transponder that may not be reporting accurate info, this is
serious question in an area I know relatively little about but which a
lot of us are considering these days.

Chip Bearden
ASW 24 "JB"
USA

According to my understanding of the regulations, 91.413, and what I
was told by Airborne Electronics, the test must be done every 24
months. 91.411 refers to testing the altimeter & static for IFR every
24 months, which doesn't apply to most gliders. A calibration between
the altimeter and encoder were performed as part of the testing in
addition to all the test to ensure the transponder was transmitting
and receiving within specification.

Chip Fitzpatrick

We did a transponder/altimeter certification on a friend's glider in
my garage the night before last.
The 57mm Winter altimeter has only one external adjustment screw,
not the two of the 80mm units. This was an older altimeter, and needed
some help. It was initially 700 feet off at 4000' (home).
Help provided, both altimeter and encoder/transponder were taken
down to sea level, up to 20,000 feet, and certified. Cost was $160.00
with the tech coming to my house.
Will be doing the same with my glider (and a new 57mm altimeter) in
a week or two.
Incidentally, the adjustment screw is on the corner of the 57mm
altimeter's casing, and has wax in the access hole making it difficult
to identify. You must remove the altimeter from the panel to adjust.
Jim

wrote:
This brings up another question and complication regarding the
installation of transponders in sailplanes. The altimeter. I get a
different answer everytime I ask it, but the transponder inspection
may/may not include inspection of the altimeter. I had to install an
IFR altimeter (large size) to pass the original installation
inspection. I could not find a small size altimeter that met the
accuracy requirements. Subsequent inspectors didn't care so I went
back to my small altimeter.

The altimeter is required to meet specific accuracy standards for IFR
use, but not for VFR use. Your original inspector was wrong to require
it for your glider, unless you indicated you wanted to use it under IFR.

--
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

Eric, with respect Chip is correct. I found the FARs to be very
confusing on this subject. After some research, though, I'm pretty
sure that the following interpretation is correct:

For VFR operations the applicable paragraphs are 91.413, and Part 43
Appendices E and F. You start with 91.413(a). This requires that every
two years you must have transponder electrical checks done in
accordance with 43 Appendix F. As you'll see, if you have a Mode S
transponder there are a lot more checks, so it is more expensive.

Again for VFR, if you've just installed (or done some maintenance) on
a transponder that will be used in VFR operations, you then must
follow 91.413(b). This leads you to 43 Appendix E paragraphs (c) and
(a), which together require the static system to be leak tested,
followed by doing an alititude correspondance test between the
alitimeter and the transponder in which they must agree to within 125
feet. Notice this gets you out of paragraphs (b) and (d), which are
rigorous altimeter checks and record keeping, which makes the testing
cheaper for VFR.

For IFR operations, you start with 91.411. This leads you to comply
with the much more rigorous testing of the alitimeter under paragraphs
(b) and (d) of 43 Appendix E, and in the process of complying with
91.411 you automatically comply with 91.413 (the more limited VFR
requirements cited above).

-John

jcarlyle wrote:
Eric, with respect Chip is correct. I found the FARs to be very
confusing on this subject. After some research, though, I'm pretty
sure that the following interpretation is correct:

For VFR operations the applicable paragraphs are 91.413, and Part 43
Appendices E and F. You start with 91.413(a). This requires that every
two years you must have transponder electrical checks done in
accordance with 43 Appendix F. As you'll see, if you have a Mode S
transponder there are a lot more checks, so it is more expensive.

This part I've always accepted.

Again for VFR, if you've just installed (or done some maintenance) on
a transponder that will be used in VFR operations, you then must
follow 91.413(b). This leads you to 43 Appendix E paragraphs (c) and
(a), which together require the static system to be leak tested,
followed by doing an altitude correspondance test between the
altimeter and the transponder in which they must agree to within 125
feet. Notice this gets you out of paragraphs (b) and (d), which are
rigorous altimeter checks and record keeping, which makes the testing
cheaper for VFR.

This was the confusing one, but after going around in circles in the
CFRs for at least 30 minutes, I have to agree with you. It's confusing
because 43 Appendix E references 91.411, which is clearly IFR only. It
took a while to realize 91.413(b) points just to 43 Appendix E (c), not
to the entire 43 Appendix E. And, then (c) points back to (a)! Cheez, it
takes a flow chart to keep things straight.

It would be clear if they copied 43 E (a) and 43 E (c) and made those
paragraphs part of 91.413(b), instead of forcing you to go from section
to section, but they don't do that.

Now I'm puzzled that the regs insist on IFR quality data correspondence
for the initial installation, but with no checks after that as long as
you don't change anything.

--
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

While you're pondering the logic of the regs insisting on VFR
transponder/altimeter data correspondance after installation or
maintenance, consider the implications of 91.411(c). This IFR
requirement considers TSOed altimeters and encoders to be tested and
inspected as of the date of their manufacture. The way I read this,
you don't have to perform the checks in 43 Appendix E on intial IFR
transponder installation, you just have to do them within 24 months
after their manufacturing date.

-John

On May 3, 5:22 pm, Eric Greenwell wrote:
Now I'm puzzled that the regs insist on IFR quality data correspondence
for the initial installation, but with no checks after that as long as
you don't change anything.

--
Eric Greenwell - Washington State, USA

This is a curious question. Presumably you went to the expense and
bother to install the transponder so that ATC and TCAS equipped aircraft
can determine your position and altitude and take appropriate action. If
your equipment isn't working properly, then when you most need it the
other aircraft won't have the correct info they need to avoid a collision.

This is safety equipment. If you're going to carry it, get it properly
maintained. Do you get your parachute repacked regularly? Same issue.

Steve

Chip Bearden wrote:
In the east (i.e., where we're generally below 10,000 ft.), if a
glider is not flying in Class A, B, or C airspace, does a transponder
fall under the 24-month inspection rule? From the latest AOPA email
advisory (emphasis added):

****************
Question: I know an altimeter inspection is only required when flying
under IFR, but what about the transponder inspection? Is it required
for both VFR and IFR flights?

Answer: Unlike the altimeter inspection that is required to operate
under IFR, A TRANSPONDER INSPECTION IS DICTATED BY THE AIRSPACE
THROUGH WHICH YOU ARE. A transponder used in airspace specified by FAR
91.215 (which includes operation within Class A, within or above Class
B and C, and above 10,000 ft msl) must be inspected within the
preceding 24 calendar months for both VFR and IFR flights. For more
information, view the AOPA online subject report on Aircraft
Inspections.
****************

I checked the cited FAR (and the others it references) and I'm still
not sure of the answer. Ignoring the safety issues of flying around
with a transponder that may not be reporting accurate info, this is
serious question in an area I know relatively little about but which a
lot of us are considering these days.

Chip Bearden
ASW 24 "JB"
USA

I think the regs on FAA required maintenance checks were written when
equipment had hand cranks and vacuum tubes. Avionics has been pretty much
reliable and drift free for several decades. Getting a transponder check
from ATC should be "good enough" for VFR.

bumper


"Steve" wrote in message
news:gcjTj.743$Jb2.588@trndny03...
This is a curious question. Presumably you went to the expense and bother
to install the transponder so that ATC and TCAS equipped aircraft can
determine your position and altitude and take appropriate action. If your
equipment isn't working properly, then when you most need it the other
aircraft won't have the correct info they need to avoid a collision.

This is safety equipment. If you're going to carry it, get it properly
maintained. Do you get your parachute repacked regularly? Same issue.

Steve

Chip Bearden wrote:
In the east (i.e., where we're generally below 10,000 ft.), if a
glider is not flying in Class A, B, or C airspace, does a transponder
fall under the 24-month inspection rule? From the latest AOPA email
advisory (emphasis added):

****************
Question: I know an altimeter inspection is only required when flying
under IFR, but what about the transponder inspection? Is it required
for both VFR and IFR flights?

Answer: Unlike the altimeter inspection that is required to operate
under IFR, A TRANSPONDER INSPECTION IS DICTATED BY THE AIRSPACE
THROUGH WHICH YOU ARE. A transponder used in airspace specified by FAR
91.215 (which includes operation within Class A, within or above Class
B and C, and above 10,000 ft msl) must be inspected within the
preceding 24 calendar months for both VFR and IFR flights. For more
information, view the AOPA online subject report on Aircraft
Inspections.
****************

I checked the cited FAR (and the others it references) and I'm still
not sure of the answer. Ignoring the safety issues of flying around
with a transponder that may not be reporting accurate info, this is
serious question in an area I know relatively little about but which a
lot of us are considering these days.

Chip Bearden
ASW 24 "JB"
USA