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Terminal Arrival Area (TAA) (Part One)

in The National Airspace System

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.

Figure 8-12. Basic “T” Design of Terminal Arrival Area (TAA) and Legend.

Figure 8-12. Basic “T” Design of Terminal Arrival Area (TAA) and Legend. [click image to enlarge]

Figure 8-12. Basic “T” Design of Terminal Arrival Area (TAA) and Legend.

Figure 8-12. (cont…) Basic “T” Design of Terminal Arrival Area (TAA) and Legend. [click image to enlarge]

In order to accommodate descent from a high en route altitude to the initial segment altitude, a hold in lieu of a procedure turn provides the aircraft with an extended distance for the necessary descent gradient. The holding pattern constructed for this purpose is always established on the center IAF waypoint. Other modifications may be required for parallel runways, or special operational requirements. When published, the RNAV chart will depict the TAA through the use of icons representing each TAA associated with the RNAV procedure. These icons are depicted in the plan view of the approach, generally arranged on the chart in accordance with their position relative to the aircraft’s arrival from the en route structure.

Course Reversal Elements in Plan View and Profile View

Course reversals included in an IAP are depicted in one of three different ways: a 45°/180° procedure turn, a holding pattern in lieu of procedure turn, or a teardrop procedure. The maneuvers are required when it is necessary to reverse direction to establish the aircraft inbound on an intermediate or final approach course. Components of the required procedure are depicted in the plan view and the profile view. The maneuver must be completed within the distance and at the minimum altitude specified in the profile view. Pilots should coordinate with the appropriate ATC facility relating to course reversal during the IAP.

Procedure Turns

A procedure turn barbed arrow (see below) indicates the direction or side of the outbound course on which the procedure turn is made. [Figure 8-13] Headings are provided for course reversal using the 45° procedure turn. However, the point at which the turn may be commenced, and the type and rate of turn is left to the discretion of the pilot. Some of the options are the 45° procedure turn, the racetrack pattern, the teardrop procedure turn, or the 80°/260° course reversal. The absence of the procedure turn barbed arrow in the plan view indicates that a procedure turn is not authorized for that procedure. A maximum procedure turn speed of not greater than 200 knots indicated airspeed (KIAS) should be observed when turning outbound over the IAF and throughout the procedure turn maneuver to ensure staying within the obstruction clearance area. The normal procedure turn distance is 10 NM. This may be reduced to a minimum of 5 NM where only Category A or helicopter aircraft are operated, or increased to as much as 15 NM to accommodate high performance aircraft. Descent below the procedure turn altitude begins after the aircraft is established on the inbound course.

Figure 8-13. 45° Procedure Turn.

Figure 8-13. 45° Procedure Turn.

The procedure turn is not required when the symbol “NoPT” appears, when radar vectoring to the final approach is provided, when conducting a timed approach, or when the procedure turn is not authorized. Pilots should contact the appropriate ATC facility when in doubt if a procedure turn is required.


Holding in Lieu of Procedure Turn

A holding pattern in lieu of a procedure turn may be specified for course reversal in some procedures. [Figure 8-14] In such cases, the holding pattern is established over an intermediate fix or a final approach fix (FAF). The holding pattern distance or time specified in the profile view must be observed. Maximum holding airspeed limitations as set forth for all holding patterns apply. The holding pattern maneuver is completed when the aircraft is established on the inbound course after executing the appropriate entry. If cleared for the approach prior to returning to the holding fix and the aircraft is at the prescribed altitude, additional circuits of the holding pattern are neither necessary nor expected by ATC. If pilots elect to make additional circuits to lose excessive altitude or to become better established on course, it is their responsibility to advise ATC upon receipt of their approach clearance. When holding in lieu of a procedure turn, the holding pattern must be followed, except when RADAR VECTORING to the final approach course is provided or when NoPT is shown on the approach course.

Figure 8-14. Holding in Lieu of Procedure Turn.

Figure 8-14. Holding in Lieu of Procedure Turn.

Teardrop Procedure

When a teardrop procedure turn is depicted and a course reversal is required, unless otherwise authorized by ATC, this type of procedure must be executed. [Figure 8-15] The teardrop procedure consists of departure from an IAF on the published outbound course followed by a turn toward and intercepting the inbound course at or prior to the intermediate fix or point. Its purpose is to permit an aircraft to reverse direction and lose considerable altitude within reasonably limited airspace. Where no fix is available to mark the beginning of the intermediate segment, it shall be assumed to commence at a point 10 NM prior to the FAF. When the facility is located on the airport, an aircraft is considered to be on final approach upon completion of the penetration turn. However, the final approach segment begins on the final approach course 10 NM from the facility.

Figure 8-15. Teardrop Procedure.

Figure 8-15. Teardrop Procedure.

The Profile View

The profile view is a depiction of the procedure from the side and illustrates the vertical approach path altitudes, headings, distances, and fixes. [Figures 8-10, 8-11, and 8-12] The view includes the minimum altitude and the maximum distance for the procedure turn, altitudes over prescribed fixes, distances between fixes, and the missed approach procedure. The profile view aids in the pilot’s interpretation of the IAP. The profile view is not drawn to scale. [Figures 8-10, 8-11, 8-12, and 8-16]

Figure 8-10. Instrument Approach Chart.

Figure 8-10. Instrument Approach Chart. [click image to enlarge]

Figure 8-11. IAP Plan View and Symbol Legends.

Figure 8-11. IAP Plan View and Symbol Legends. [click image to enlarge]

Figure 8-11. IAP Plan View and Symbol Legends.

Figure 8-11. (cont…) IAP Plan View and Symbol Legends. [click image to enlarge]

Figure 8-12. Basic “T” Design of Terminal Arrival Area (TAA) and Legend.

Figure 8-12. Basic “T” Design of Terminal Arrival Area (TAA) and Legend. [click image to enlarge]

Figure 8-12. Basic “T” Design of Terminal Arrival Area (TAA) and Legend.

Figure 8-12. (cont…) Basic “T” Design of Terminal Arrival Area (TAA) and Legend. [click image to enlarge]

The precision approach glide slope (GS) intercept altitude is a minimum altitude for GS interception after completion of the procedure turn, illustrated by an altitude number and “zigzag” line. It applies to precision approaches, and except where otherwise prescribed, also applies as a minimum altitude for crossing the FAF when the GS is inoperative or not used. Precision approach profiles also depict the GS angle of descent, threshold-crossing height (TCH), and GS altitude at the outer marker (OM).

Figure 8-16. More IAP Profi le View Features.

Figure 8-16. More IAP Profile View Features. [click image to enlarge]

Figure 8-16. More IAP Profile View Features.

Figure 8-16. (cont…) More IAP Profile View Features. [click image to enlarge]

For nonprecision approaches, a final descent is initiated and the final segment begins at either the FAF or the final approach point (FAP). The FAF is identified by use of the Maltese cross symbol in the profile view. [Figure 8-11] When no FAF is depicted, the final approach point is the point at which the aircraft is established inbound on the final approach course. [Figure 8-16]

Stepdown fixes in nonprecision procedures are provided between the FAF and the airport for authorizing a lower minimum descent altitude (MDA) after passing an obstruction. Stepdown fixes can be identified by NAVAID, NAVAID fix, waypoint or radar, and are depicted by a hash marked line. Normally, there is only one stepdown fix between the FAF and the MAP, but there can be several. If the stepdown fix cannot be identified for any reason, the minimum altitude at the stepdown fix becomes the MDA for the approach. However, circling minimums apply if they are higher than the stepdown fix minimum altitude, and a circling approach is required.


The visual descent point (VDP) is a defined point on the final approach course of a nonprecision straight-in approach procedure. A normal descent from the MDA to the runway touchdown point may be commenced, provided visual reference is established. The VDP is identified on the profile view of the approach chart by the symbol “V.” [Figure 8-12]

The MAP varies depending upon the approach flown. For the ILS, the MAP is at the decision altitude/decision height (DA/DH). For nonprecision procedures, the pilot determines the MAP by timing from FAF when the approach aid is away from the airport, by a fix or NAVAID when the navigation facility is located on the field, or by waypoints as defined by GPS or VOR/DME RNAV. The pilot may execute the MAP early, but pilots should, unless otherwise cleared by ATC, fly the IAP as specified on the approach plate to the MAP at or above the MDA or DA/DH before executing a turning maneuver.

A complete description of the missed approach procedure appears in the pilot briefing section. [Figure 8-16] Icons indicating what is to be accomplished at the MAP are located in the profile view. When initiating a missed approach, the pilot will be directed to climb straight ahead (e.g., “Climb to 2,000”) or commence a turning climb to a specified altitude (e.g., “Climbing right turn to 2,000”). In some cases, the procedure will direct the pilot to climb straight ahead to an initial altitude, then turn or enter a climbing turn to the holding altitude (e.g., “Climb to 900, then climbing right turn to 2,500 direct ABC VOR and hold”).

When the missed approach procedure specifies holding at a facility or fix, the pilot proceeds according to the missed approach track and pattern depicted on the plan view. An alternate missed approach procedure may also be issued by ATC. The textual description will also specify the NAVAID(s) or radials that identify the holding fix.

The profile view also depicts minimum, maximum, recommended, and mandatory block altitudes used in approaches. The minimum altitude is depicted with the altitude underscored. On final approach, aircraft are required to maintain an altitude at or above the depicted altitude until reaching the subsequent fix. The maximum altitude will be depicted with the altitude overscored, and aircraft must remain at or below the depicted altitude. Mandatory altitudes will be depicted with the altitude both underscored and overscored, and altitude is to be maintained at the depicted value. Recommended altitudes are advisory altitudes and are neither over- nor underscored. When an over- or underscore spans two numbers, a mandatory block altitude is indicated, and aircraft are required to maintain altitude within the range of the two numbers. [Figures 8-11 and 8-12]

Figure 8-17. Vertical Descent Angle (VDA).

Figure 8-17. Vertical Descent Angle (VDA).

The Vertical Descent Angle (VDA) found on nonprecision approach charts provides the pilot with information required to establish a stabilized approach descent from the FAF or stepdown fix to the threshold crossing height (TCH). [Figure 8-17] Pilots can use the published angle and estimated or actual ground speed to find a target rate of descent using the rate of descent table in the back of the TPP.

 

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