CAT IIIC minimums

A question: the landing minimums section for ILS CAT-III approaches
may have separate lines for A, B, and C. In some cases the C line
has an "NA" for visibility, and on some other plates the whole C
line is missing. So, what's the difference? Does "NA" mean "not
authorized", i.e. CAT-IIIC cannot be used?

Thanks!


Andrey

Andrey Serbinenko wrote:
A question: the landing minimums section for ILS CAT-III approaches
may have separate lines for A, B, and C. In some cases the C line
has an "NA" for visibility, and on some other plates the whole C
line is missing. So, what's the difference? Does "NA" mean "not
authorized", i.e. CAT-IIIC cannot be used?

Thanks!


Andrey

NA indeed means Not Authorized.

OK, then why do they include IIIC line with an "NA" on some
plates and omit it altogether on others?


Sam Spade wrote:
Andrey Serbinenko wrote:
A question: the landing minimums section for ILS CAT-III approaches
may have separate lines for A, B, and C. In some cases the C line
has an "NA" for visibility, and on some other plates the whole C
line is missing. So, what's the difference? Does "NA" mean "not
authorized", i.e. CAT-IIIC cannot be used?

Thanks!


Andrey

NA indeed means Not Authorized.

-----Original Message-----
From: Andrey Serbinenko ]
Posted At: Sunday, August 06, 2006 2:42 PM
Posted To: rec.aviation.ifr
Conversation: CAT IIIC minimums
Subject: CAT IIIC minimums

A question: the landing minimums section for ILS CAT-III approaches
may have separate lines for A, B, and C. In some cases the C line
has an "NA" for visibility, and on some other plates the whole C
line is missing. So, what's the difference? Does "NA" mean "not
authorized", i.e. CAT-IIIC cannot be used?

Thanks!


Andrey

Can you give us a particular plate or approach to reference please?

Sure. Hmm... what do we have here... NACO north-east... Okay, he
Newark Liberty, KEWR, ILS RWY 4R (CAT III) lists visibility
S-ILS 4R for CAT IIIC as NA.
New York JFK, KJFK, ILS RWY 4R (CAT III) lists visibilities
S-ILS 4R for CAT IIIA and CAT IIIB, but no CAT IIIC line there.

Andrey


Jim Carter wrote:

-----Original Message-----
From: Andrey Serbinenko ]
Posted At: Sunday, August 06, 2006 2:42 PM
Posted To: rec.aviation.ifr
Conversation: CAT IIIC minimums
Subject: CAT IIIC minimums

A question: the landing minimums section for ILS CAT-III approaches
may have separate lines for A, B, and C. In some cases the C line
has an "NA" for visibility, and on some other plates the whole C
line is missing. So, what's the difference? Does "NA" mean "not
authorized", i.e. CAT-IIIC cannot be used?

Thanks!


Andrey

Can you give us a particular plate or approach to reference please?

From FAA's 2004 Instrument Procedures Handbook, chapter 5:
[...]
The weather conditions encountered in CAT III opera-
tions range from an area where visual references are
adequate for manual rollout in CAT IIIa, to an area
where visual references are inadequate even for taxi
operations in CAT IIIc. To date, no U.S. operator has
received approval for CAT IIIc in OpsSpecs.
[...]

But I heard that airlines are not only authorized, but required
to do an auto-land every so often. Am I missing something here?

Andrey


Jim Carter wrote:

-----Original Message-----
From: Andrey Serbinenko ]
Posted At: Sunday, August 06, 2006 2:42 PM
Posted To: rec.aviation.ifr
Conversation: CAT IIIC minimums
Subject: CAT IIIC minimums

A question: the landing minimums section for ILS CAT-III approaches
may have separate lines for A, B, and C. In some cases the C line
has an "NA" for visibility, and on some other plates the whole C
line is missing. So, what's the difference? Does "NA" mean "not
authorized", i.e. CAT-IIIC cannot be used?

Thanks!


Andrey

Can you give us a particular plate or approach to reference please?

-----Original Message-----

From: Andrey Serbinenko ]

Posted At: Sunday, August 06, 2006 10:36 PM

Posted To: rec.aviation.ifr

Conversation: CAT IIIC minimums

Subject: CAT IIIC minimums



..



Can you give us a particular plate or approach to reference please?





Okay, I have an answer and a reference (highlights are mine).



The lowest authorized ILS minimums, with all required ground and
airborne systems components operative, are



.. Category I - Decision Height (DH) 200 feet and Runway Visual Range
(RVR) 2,400 feet (with touchdown zone and centerline lighting, RVR 1800
feet),

.. Category II - DH 100 feet and RVR 1,200 feet,

.. Category IIIa - No DH or DH below 100 feet and RVR not less than 700
feet,

.. Category IIIb - No DH or DH below 50 feet and RVR less than 700 feet
but not less than 150 feet, and

.. Category IIIc - No DH and no RVR limitation.



NOTE: Special authorization and equipment are required for Category II
and III.



I found the above on page 5-49 of the Instrument Procedures Handbook at
http://www.faa.gov/library/manuals/a...cedures_handbo
ok/



So contrary to what others have suggested, the NA does not mean "not
authorized"; rather, it means "not applicable". There is "No DH and no
RVR limitation" for the CAT IIIc approach. Category IIIc conditions has
visibility insufficient for taxi operations according to the text on
page 5-48.



There is no CAT IIIc approach into JFK for runway 4R which is why it is
not listed on the plate.



There is a CAT IIIc approach into Newark; the NA is under the visibility
requirement.

You don't need CAT IIIc for autoland. Cat IIIa is sufficient. I'm
sure one of the airline drivers will chime in - ceiling/visibility
ignored for a moment, can't you autoland off a normal CAT I ILS if you
so desire? It's the same LOC/GS as the CAT III beam, right? They
just flight and obstacle check to a greater tolerance for the CAT III
authorization?


On Mon, 07 Aug 2006 04:37:55 +0000, Andrey Serbinenko
wrote:

From FAA's 2004 Instrument Procedures Handbook, chapter 5:
[...]
The weather conditions encountered in CAT III opera-
tions range from an area where visual references are
adequate for manual rollout in CAT IIIa, to an area
where visual references are inadequate even for taxi
operations in CAT IIIc. To date, no U.S. operator has
received approval for CAT IIIc in OpsSpecs.
[...]

But I heard that airlines are not only authorized, but required
to do an auto-land every so often. Am I missing something here?

Andrey


Jim Carter wrote:

-----Original Message-----
From: Andrey Serbinenko ]
Posted At: Sunday, August 06, 2006 2:42 PM
Posted To: rec.aviation.ifr
Conversation: CAT IIIC minimums
Subject: CAT IIIC minimums

A question: the landing minimums section for ILS CAT-III approaches
may have separate lines for A, B, and C. In some cases the C line
has an "NA" for visibility, and on some other plates the whole C
line is missing. So, what's the difference? Does "NA" mean "not
authorized", i.e. CAT-IIIC cannot be used?

Thanks!


Andrey

Can you give us a particular plate or approach to reference please?

Andrey Serbinenko wrote
But I heard that airlines are not only authorized, but required
to do an auto-land every so often. Am I missing something here?

'Autoland' and 'Approach CAT' are two separate subjects. It is true
that 'autoland' is a requirement for the conduct of an approach and
landing if the wx conditions are below CATII minimums, but autoland
can also be used in VFR conditions.

The reason for the requirement to conduct autolandings every so often
(we had that requirement at the old PanAm) is to insure that the
equipment remains in calibration. If the autolandings were not logged,
the equipment had to be removed from the a/c and bench calibrated at
scheduled intervals.

Many of our PanAm B-727s had autoland capability with only a CATII
approach capability.

Bob Moore
ATP B-707 B-727
PanAm (retired)

"Jim Carter" wrote in message
news:001c01c6b9e5$41b26ee0$4001a8c0@omnibook6100.. .
The lowest authorized ILS minimums, with all required ground and airborne
systems components operative, are
. Category I - Decision Height (DH) 200 feet and Runway Visual Range (RVR)
2,400 feet (with touchdown zone and centerline lighting, RVR 1800 feet),
. Category II - DH 100 feet and RVR 1,200 feet,
. Category IIIa - No DH or DH below 100 feet and RVR not less than 700
feet,
. Category IIIb - No DH or DH below 50 feet and RVR less than 700 feet but
not less than 150 feet, and
. Category IIIc - No DH and no RVR limitation.

I found the above on page 5-49 of the Instrument Procedures Handbook at
http://www.faa.gov/library/manuals/a...ures_handbook/

So contrary to what others have suggested, the NA does not mean "not
authorized";
rather, it means "not applicable".

No, NA means "not authorized". See
http://www.naco.faa.gov/content/naco..._IAP_Intro.pdf , p.
53. (Also, Jeppesen's Instrument/Commercial Manual, Appendix B, lists NA as
an abbreviation for "not authorized".)

The material you cited above is entirely consistent with the "not
authorized" meaning.

There is no CAT IIIc approach into JFK for runway 4R

Sorry, can you say how you arrived at that conclusion?

which is why it is not listed on the plate.

Couldn't it be unlisted because there are no DA or RVR limitations to list?

--Gary