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Instrument Flying Handbook
The National Airspace System
Terminal Arrival Area (TAA)

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Instrument Flying


Table of Contents

Chapter 1. Human Factors
Chapter 2. Aerodynamic Factors
Chapter 3. Flight Instruments
Chapter 4. Section I
Airplane Attitude Instrument
Using Analog Instrumentation
Chapter 4. Section II
Airplane Attitude Instrument
Using an Electronic Flight

Chapter 5. Section I
Airplane Basic
Flight Maneuvers
Using Analog Instrumentation
Chapter 5. Section II
Airplane Basic
Flight Maneuvers
Using an Electronic Flight

Chapter 6. Helicopter
Attitude Instrument Flying

Chapter 7. Navigation Systems
Chapter 8. The National
Airspace System

Chapter 9. The Air Traffic
Control System

Chapter 10. IFR Flight
Chapter 11. Emergency

Some NACG charts contain a reference or distance circle
with a specified radius (10 NM is most common). Normally,
approach features within the plan view are shown to scale;
however, only the data within the reference circle is always
drawn to scale,

Concentric dashed circles, or concentric rings around the
distance circle, are used when the information necessary to
the procedure will not fit to scale within the limits of the plan
view area. They serve as a means to systematically arrange
this information in its relative position outside and beyond
the reference circle. These concentric rings are labeled en
route facilities and feeder facilities.

The primary airport depicted in the plan view is drawn with
enough detail to show the runway orientation and final
approach course alignment. Airports other than the primary
approach airport are not normally depicted in the NACG
plan view.

Known spot elevations are indicated on the plan view with a
dot in MSL altitude. The largest dot and number combination
indicates the highest elevation. An inverted "V" with a dot
in the center depicts an obstacle. The highest obstacle is
indicated with a bolder, larger version of the same symbol,
[Figure 8-11]

The MSA circle appears in the plan view, except in approaches
for which the Terminal Arrival Area (TAA) format is used or
appropriate NAVAIDs (e.g., VOR or NDB)
are unavailable, The NSA is provided for emergency purposes
only and guarantees 1,000 feet obstruction clearance in the
sector indicated with reference to the bearings in the
circle. For conventional navigation systems.
the MSA is normally based on the primary omnidirectional
facility (NAVAID) on which the IAP is predicated, The MSA
depiction on the approach chart contains the facility identifier
of the NAVAID used to determine the MSA altitudes. For
RNAV approaches, the MSA is based on the runway waypoint
for straight-in approaches, or the airport waypoint for circling
approaches. For GPS approaches, the MSA center header will
be the missed approach waypoint. The MSL altitudes appear
in boxes within the circle, which is typically a 25 NM radius
unless otherwise indicated. The MSA circle header refers to
the letter identifier of the NAVAID or waypoint that describes
the center of the circle.

NAVAIDs necessary for the completion of the instrument
procedure include the facility name, letter identifier, and
Morse code sequence. They may also furnish the frequency,
Morse code, and channel. A heavy-lined NAVAID box depicts
the primary NAVAID used for the approach. An "I" in front
of the NAVAID identifier (in figure 8-11, 'I-AVL") listed in
the NAVAID box indicates a localizer. The requirement for
an ADF, DME, or RADAR in the approach is noted in the
plan view.

Intersections, fixes, radials, and course lines describe route
and approach sequencing information. The main procedure
or final approach course is a thick, solid line. A
DME arc, which is part of the main procedure course, is
also represented as a thick, solid line. A feeder
route is depicted with a medium line and provides
heading, altitude, and distance information. (All three
components must be designated on the chart to provide a
navigable course.) Radials, such as lead radials, are shown
by thin lines. The missed approach track is drawn
using a thin hash marked line with a directional arrow.
A visual flight path segment
appears as a thick dashed line with a directional arrow.
IAFs are charted IAF when associated with
a NAVAID or when freestanding.

The missed approach holding pattern track is represented with
a thin-dashed line. When collocated, the missed approach
holding pattern and procedure turn holding pattern are
indicated as a solid, black line. Arrival holding patterns are
depicted as thin, solid lines.

Terminal Arrival Area (TAA)

The design objective of the TAA procedure is to provide
a transition method for arriving aircraft with GPS/RNAV
equipment. TAAs will also eliminate or reduce the need
for feeder routes, departure extensions, and procedure
turns or course reversal. The TAA is controlled airspace
established in conjunction with the standard or modified
RNAV approach configurations.

The standard TAA has three areas: straight-in, left base, and
right base. The arc boundaries of the three areas of the TAA
are published portions of the approach and allow aircraft to
transition from the en route structure direct to the nearest
IAF. When crossing the boundary of each of these areas or
when released by ATC within the area, the pilot is expected
to proceed direct to the appropriate waypoint IAF for the
approach area being flown. A pilot has the option in all areas
of proceeding directly to the holding pattern.

The TAA has a "T" structure that normally provides a NoPT
for aircraft using the approach. [Figure 8-12] The TAA
provides the pilot and air traffic controller with an efficient
method for routing traffic from the en route to the terminal
structure. The basic "T' contained in the TAA normally
aligns the procedure on runway centerline, with the missed
approach point: (MAP) located at the threshold, the FAF 5
NM from the threshold, and the intermediate fix (IF) 5 NM
from the FAF.