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?

-----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.

"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

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

From: Gary Drescher ]

Posted At: Monday, August 07, 2006 8:13 AM

Posted To: rec.aviation.ifr

Conversation: CAT IIIC minimums

Subject: CAT IIIC minimums



"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

....

I found ... on page 5-49 of the Instrument Procedures Handbook at




http://www.faa.gov/library/manuals/a...ocedures_handb
oo

k/



....



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.





Gary,

I pulled up the pdf file you supplied as reference and had adobe
search for the "not authorized" phrase. There is only one instance found
under the Alternate Minimums paragraph on page 53: "If NA appears,
alternate minimums are not authorized due to unmonitored facility or
absence of weather reporting service." I did not reference Jeppesen
because they are not the authority for this information.



Could this be a case of NA meaning one thing for CAT IIIc and
something else for other purposes? It probably would have made more
sense if the visibility requirement was shown as not required or
inapplicable.



How could an approach be authorized if the visibility requirement
is "not authorized"?





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



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





There is no CAT IIIc minima listed on the plate even though there is CAT
IIIa and b.





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



No, then it would be an unpublished approach wouldn't it? The definition
of CAT IIIc is zero/zero (more explicit language is found in my original
reference). The approach would be listed on the JFK plate if it was
approved and published. The EWS plate lists all three approach minima.

Jim Carter wrote:





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

Where do you get that idea? From an incorrectly printed Jepp chart perhaps?

Check FAR 97.3, and I quote:

(n) "NA" means not authorized.

-----Original Message-----
From: Sam Spade ]
Posted At: Monday, August 07, 2006 8:27 AM
Posted To: rec.aviation.ifr
Conversation: CAT IIIC minimums
Subject: CAT IIIC minimums

Jim Carter wrote:


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

Where do you get that idea? From an incorrectly printed Jepp chart
perhaps?

Check FAR 97.3, and I quote:

(n) "NA" means not authorized.

Please notice the quote I pasted from the TERPS manual. Also, please
read the notes on the pages I originally referenced. They state that
there is no applicable RVR (visibility) requirement for CAT IIIc. They
also state that CAT IIIc is operation with visibility unsuitable for
taxi.

How could an approach be authorized yet have the visibility requirements
part of it be not authorized? When you take that NACO plate into
consideration in light of the TERPS manual, not applicable is a
reasonable conclusion.