CKonikoff wrote:

Sorry, but I missed the original posting. I believe that at GPT there is no
V522, only V552. Maybe they charted something wrong and the NOTAM was to
change the error, V522, to the correct airway, V552.

DC 5/0505 GPT FI/T GULFPORT-BILOXI INTL, GULFPORT, MS.
ILS OR LOC RWY 14, AMDT 14...
CHANGE PLANVIEW NOTE: PROCEDURE NA FOR ARRIVALS
AT CAESA VIA V552 WESTBOUND VICE V522 WESTBOUND.

IF and only IF I was wanting to do a full procedure approach coming from
any other direction then westbound, would a procedure turn be authorized
based on the above FDC? If not, what is this FDC about?

They made a mistake on the airway number. What the NOTAM clarifies is that you
cannot do the procedure at all arriving on V552 from the east, because it
exceeds the 120-degree course change limitation of TERPs Paragraph 220. CAESA is
on V552, so it is not possible to do the procedure turn arriving on that route.
Arriving on V-552 from the west results in less than a 120-degree course change
at CAESA, and because "NoPT" is authorized after CAESA, it's straight-in from
that direction on V-552.

It's only been in the past three years or so that they have started adding these
course change limitation notes to IAPs, although the requirement has always
existed in TERPS (subparagraph "b" below):

220. FEEDER ROUTES. When the IAF is part of the enroute structure there may be
no need to designate additional routes for aircraft to proceed to the IAF. In
some cases, however, it is necessary to designate feeder routes from the enroute
structure to the IAF. Only those feeder routes which provide an operational
advantage shall be established and published. These should coincide with the
local air traffic flow. The length of the feeder route shall not exceed the
operational service volume of the facilities which provide navigational guidance
unless additional frequency protection is provided. Enroute airway obstacle
clearance criteria shall apply to feeder routes. The minimum altitude
established on feeder routes shall not be less than the altitude established at
the IAF.
a. Construction of a feeder route connecting to a course reversal segment. The
area considered for obstacle evaluation is oriented along the feeder route at a
width appropriate to the type of route (VOR or NDB). The area terminates at the
course reversal fix, and is defined by a line perpendicular to the feeder course
through the course reversal fix.
b. The angle of intersection between the feeder route course and the next
straight segment (feeder/initial) course shall not exceed 120°.
c. Descent Gradient. The OPTIMUM descent gradient in the feeder route is 250
feet per mile. Where a higher descent gradient is necessary, the MAXIMUM
permissible gradient is 500 feet per mile. The OPTIMUM descent gradient for high
altitude penetrations is 800 feet per mile. Where a higher descent gradient is
necessary, the MAXIMUM permissible is 1,000 feet per mile.