Aeronautical Information Manual (AIM), page 347

Index   346 -- Page 347 -- 348

12/10/15                                                                                                          AIM

either case, the pilot should proceed direct to the IAF         authorize a pilot to descend to a lower TAA altitude.
or to the IF/IAF associated with the sector that the            If a pilot desires a lower altitude without an approach
aircraft will enter the TAA and join the approach               clearance, request the lower TAA altitude from ATC.
course from that point and if required by that sector           Pilots not sure of the clearance should confirm their
(i.e., sector is not labeled "NoPT), complete the               clearance with ATC or request a specific clearance.
HILPT course reversal.                                          Pilots entering the TAA with two-way radio commu-
NOTE-                                                           nications failure (14 CFR Section 91.185, IFR
If approaching with a TO bearing that is on a sector bound-     Operations: Two-way Radio Communications Fail-
ary, the pilot is expected to proceed in accordance with a      ure), must maintain the highest altitude prescribed by
"NoPT" routing unless otherwise instructed by ATC.              Section 91.185(c)(2) until arriving at the appropriate
     5. Altitudes published within the TAA replace
the MSA altitude. However, unlike MSA altitudes the
                                                                       (b) Once cleared for the approach, pilots may
TAA altitudes are operationally usable altitudes.
                                                                descend in the TAA sector to the minimum altitude
These altitudes provide at least 1,000 feet of obstacle
                                                                depicted within the defined area/subdivision, unless
clearance, more in mountainous areas. It is important
                                                                instructed otherwise by air traffic control. Pilots
that the pilot knows which area of the TAA the aircraft
                                                                should plan their descent within the TAA to permit a
will enter in order to comply with the minimum alti-
                                                                normal descent from the IF/IAF to the FAF. In
tude requirements. The pilot can determine which
                                                                FIG 5-4-4, pilots within the left or right-base areas
area of the TAA the aircraft will enter by determining
                                                                are expected to maintain a minimum altitude of 6,000
the magnetic bearing of the aircraft TO the fix labeled
                                                                feet until within 17 NM of the associated IAF. After
IF/IAF. The bearing should then be compared to the
                                                                crossing the 17 NM arc, descent is authorized to the
published lateral boundary bearings that define the
                                                                lower charted altitudes. Pilots approaching from the
TAA areas. Do not use magnetic bearing to the
                                                                northwest are expected to maintain a minimum alti-
right-base or left-base IAFs to determine position.
                                                                tude of 6,000 feet, and when within 22 NM of the
       (a) An ATC clearance direct to an IAF or to              IF/IAF, descend to a minimum altitude of 2,000 feet
the IF/IAF without an approach clearance does not               MSL until crossing the IF/IAF.
                                                         FIG 5-4-4
                                                 Sectored TAA Areas

Arrival Procedures                                                                                             5-4-11

Page 347 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   346 -- Page 347 -- 348