Planning the Descent and Approach
ATC arrival procedures and flight deck workload are affected
by weather conditions, traffic density, aircraft equipment,
and radar availability.
When landing at an airport with approach control services and
where two or more IAPs are published, information on the
type of approach to expect is provided in advance of arrival
or vectors are provided to a visual approach. This information
is broadcast either on automated terminal information
service (ATIS) or by a controller. It is not furnished when
the visibility is 3 miles or more and the ceiling is at or above
the highest initial approach altitude established for any low
altitude IAP for the airport.
The purpose of this information is to help the pilot plan arrival
actions; however, it is not an ATC clearance or commitment
and is subject to change. Fluctuating weather, shifting
winds, blocked runway, etc., are conditions that may result
in changes to the approach information previously received.
It is important for a pilot to advise ATC immediately if he
or she is unable to execute the approach or prefers another
type of approach.
If the destination is an airport without an operating control
tower and has automated weather data with broadcast
capability, the pilot should monitor the automated surface
observing system/automated weather observing system
(ASOS/AWOS) frequency to ascertain the current weather for
the airport. ATC should be advised that weather information
has been received and what the pilot’s intentions are.
When the approach to be executed has been determined, the
pilot should plan for and request a descent to the appropriate
altitude prior to the initial approach fix (IAF) or transition
route depicted on the IAP. When flying the transition route,
a pilot should maintain the last assigned altitude until ATC
gives the instructions “cleared for the approach.” Lower
altitudes can be requested to bring the transition route
altitude closer to the required altitude at the initial approach
fix. When ATC uses the phrase “at pilot’s discretion” in the
altitude information of a clearance, the pilot has the option
to start a descent at any rate and may level off temporarily
at any intermediate altitude. However, once an altitude has
been vacated, return to that altitude is not authorized without
a clearance. When ATC has not used the term “at pilot’s
discretion” nor imposed any descent restrictions, initiate
descent promptly upon acknowledgment of the clearance.
Descend at an optimum rate (consistent with the operating
characteristics of the aircraft) to 1,000 feet above the assigned
altitude. Then attempt to descend at a rate of between 500 and
1,500 fpm until the assigned altitude is reached. If at anytime
a) When vacating any previously assigned altitude
or flight level for a newly assigned altitude or
flight level
b) When an altitude change is made if operating on
a clearance specifying VFR-on-top
c) When unable to climb/descend at a rate of at least
500 feet per minute (fpm)
d) When an approach has been missed (Request
clearance for specific action (to alternative
airport, another approach, etc.))
e) Change in average true airspeed (at cruising
altitude) when it varies by 5 percent or 10 knots
(whichever is greater) from that filed in the flight
plan
f) The time and altitude upon reaching a holding fix
or point to which cleared
g) When leaving any assigned holding fix or point
NOTE: The reports in (f) and (g) may be omitted
by pilots of aircraft involved in instrument
training at military terminal area facilities when
radar service is being provided.
h) Any loss in controlled airspace of VOR,
TACAN, ADF, low frequency navigation
receiver capability, global positioning system
(GPS) anomalies while using installed IFR-
certified GPS/Global Navigation Satellite
Systems (GNSS) receivers, complete or partial
loss of ILS receiver capability, or impairment of
air/ground communications capability. Reports
should include aircraft identification, equipment
affected, degree to which the capability to operate
under IFR in the ATC system is impaired, and
the nature and extent of assistance desired from
ATC.
i) Any information relating to the safety of flight.
2. When not in radar contact:
a) When leaving the final approach fix inbound on
final approach (nonprecision approach), or when
leaving the outer marker or fix used in lieu of the
outer marker inbound on final approach (precision
approach).
b) A corrected estimate at any time it becomes
apparent that an estimate as previously submitted
is in error in excess of 3 minutes.
Any pilot who encounters weather conditions that have not
been forecast, or hazardous conditions which have been
forecast, is expected to forward a report of such weather to
ATC.
Figure 10-3. Standard terminal arrival route (STAR).
SC-4, 16 DEC 2010 to 13 JAN 2011
SC-4, 16 DEC 2010 to 13 JAN 2011
Figure 10-3. Standard terminal arrival route (STAR).
a pilot is unable to maintain a descent rate of at least 500 fpm,
advise ATC. Also advise ATC if it is necessary to level off
at an intermediate altitude during descent. An exception to
this is when leveling off at 10,000 feet mean sea level (MSL)
on descent or 2,500 feet above airport elevation (prior to
entering a Class B, Class C, or Class D surface area) when
required for speed reduction.
Standard Terminal Arrival Routes (STARs)
Standard Terminal Arrival Routes (STARs) (as described
in Chapter 1) have been established to simplify clearance
delivery procedures for arriving aircraft at certain areas
having high density traffic. A STAR serves a purpose
parallel to that of a DP for departing traffic. [Figure 10-3]
Abeam
Figure 10-4. Standard holding pattern - no winid. Figure 10-4. Standard holding pattern—no wind.
The following points regarding STARs are important to
remember:
1. All STARs are contained in the Terminal Procedures
Publication (TPP), along with the IAP charts for the
destination airport. The AIM also describes STAR
procedures.
2. If the destination is a location for which STARs
have been published, a pilot may be issued a
clearance containing a STAR whenever ATC deems
it appropriate. To accept the clearance, a pilot must
possess at least the approved textual description.
3. It is the pilot’s responsibility to either accept or refuse
an issued STAR. If a STAR will not or cannot be used,
advise ATC by placing “NO STAR” in the remarks
section of the filed flight plan or by advising ATC.
4. If a STAR is accepted in a clearance, compliance is
mandatory.
Substitutes for Inoperative or Unusable
Components
The basic ground components of an ILS are the localizer,
glideslope, outer marker, middle marker, and inner marker
(when installed). A compass locator or precision radar may
be substituted for the outer or middle marker. Distance
measuring equipment (DME), VOR, or nondirectional
beacon (NDB) fixes authorized in the standard IAP or
surveillance radar may be substituted for the outer marker.
Additionally, IFR-certified GPS equipment, operated in
accordance with Advisory Circular (AC) 90-94, Guidelines
for Using Global Positioning System Equipment for IFR
En Route and Terminal Operations and for Nonprecision
Instrument Approaches in the United States National
Airspace System, may be substituted for ADF and DME
equipment, except when flying NDB IAP. Specifically, GPS
can be substituted for ADF and DME equipment when:
1. Flying a DME arc;
2. Navigating TO/FROM an NDB;
3. Determining the aircraft position over an NDB;
4. Determining the aircraft position over a fix made up
of a crossing NDB bearing;
5. Holding over an NDB;
6. Determining aircraft position over a DME fix.
Holding Procedures
Depending upon traffic and weather conditions, holding may
be required. Holding is a predetermined maneuver that keeps
aircraft within a specified airspace while awaiting further
clearance from ATC. A standard holding pattern uses right
turns, and a nonstandard holding pattern uses left turns. The
ATC clearance always specifies left turns when a nonstandard
pattern is to be flown.
Standard Holding Pattern (No Wind)
In a standard holding pattern with no winds [Figure 10-4], the
aircraft follows the specified course inbound to the holding
fix, turns 180° to the right, flies a parallel straight course
outbound for 1 minute, turns 180° to the right, and flies the
inbound course to the fix.
Standard Holding Pattern (With Wind)
A standard symmetrical holding pattern cannot be flown
when winds exist. In those situations, the pilot is expected to:
1. Compensate for the effect of a known wind except
when turning.
2. Adjust outbound timing to achieve a 1-minute (1 1⁄2
minutes above 14,000 feet) inbound leg.
Figure 10-5 illustrates the holding track followed with a left
crosswind. The effect of wind is counteracted by applying
drift corrections to the inbound and outbound legs and by
applying time allowances to the outbound leg.
Holding Instructions
If an aircraft arrives at a clearance limit before receiving
clearance beyond the fix, ATC expects the pilot to maintain
the last assigned altitude and begin holding in accordance
with the charted holding pattern. If no holding pattern is
charted and holding instructions have not been issued, enter
a standard holding pattern on the course on which the aircraft
approached the fix and request further clearance as soon as
possible. Normally, when no delay is anticipated, ATC issues
holding instructions at least 5 minutes before the estimated
arrival at the fix. Where a holding pattern is not charted, the
ATC clearance specifies the following:
1. Direction of holding from the fix in terms of the eight
cardinal compass points (N, NE, E, SE, etc.)
Figure 10-5. Drift correction in holding pattern.
2. Holding fix (the fix may be omitted if included at the
beginning of the transmission as the clearance limit)
3. Radial, course, bearing, airway, or route on which the
aircraft is to hold.
4. Leg length in miles if DME or RNAV is to be used
(leg length is specified in minutes on pilot request or
if the controller considers it necessary).
5. Direction of turn, if left turns are to be made, because
the pilot requests or the controller considers it
necessary.
6. Time to expect-further-clearance (EFC) and any
pertinent additional delay information.
ATC instructions are also issued whenever:
1. It is determined that a delay will exceed 1 hour.
2. A revised EFC is necessary.
3. In a terminal area having a number of NAVAIDs
and approach procedures, a clearance limit may not
indicate clearly which approach procedures will
be used. On initial contact, or as soon as possible
thereafter, approach control advises the pilot of the
type of approach to expect.
4. Ceiling and/or visibility is reported as being at or
below the highest “circling minimums” established
for the airport concerned. ATC transmits a report of
current weather conditions and subsequent changes,
as necessary.
5. An aircraft is holding while awaiting approach
clearance, and the pilot advises ATC that reported
weather conditions are below minimums applicable
to the operation. In this event, ATC issues suitable
instructions to aircraft desiring either to continue
holding while awaiting weather improvement or
proceed to another airport.
Standard Entry Procedures
The entry procedures given in the AIM evolved from
extensive experimentation under a wide range of operational
conditions. The standardized procedures should be followed
to ensure that an aircraft remains within the boundaries of
the prescribed holding airspace.
When a speed reduction is required, start the reduction when
3 minutes or less from the holding fix. Cross the holding fix
initially at or below the maximum holding airspeed (MHA).
The purpose of the speed reduction is to prevent overshooting
the holding airspace limits, especially at locations where
adjacent holding patterns are close together.
All aircraft may hold at the following altitudes and maximum
holding airspeeds:
Altitude Mean Sea Level (MSL) Airspeed (KIAS)
Up to 6,000 feet 200
6,001 – 14,000 feet 230
14,001 feet and above 265
The following are exceptions to the maximum holding
airspeeds:
1. Holding patterns from 6,001 to 14,000 feet may
be restricted to a maximum airspeed of 210 knots
indicated airspeed (KIAS). This nonstandard pattern
is depicted by an icon.
2. Holding patterns may be restricted to a maximum
airspeed of 175 KIAS. This nonstandard pattern is
depicted by an icon. Holding patterns restricted to
175 KIAS are generally found on IAPs applicable to
category A and B aircraft only.
3. Holding patterns at Air Force airfields only—310
KIAS maximum, unless otherwise depicted.
4. Holding patterns at Navy airfields only—230 KIAS
maximum, unless otherwise depicted.
5. The pilot of an aircraft unable to comply with
maximum airspeed restrictions should notify ATC.
Figure 10-6. Holding pattern entry procedures.
Figure 10-6. Holding pattern entry procedures. 240°
330°
240°
330°
045° 315° 0°
Figure 10-7. Holding -outbound timing Figure 10-7. Holding—outbound timing.
While other entry procedures may enable the aircraft to
enter the holding pattern and remain within protected
airspace, the parallel, teardrop, and direct entries are the
procedures for entry and holding recommended by the
FAA. Additionally, paragraph 5-3-7 in the AIM should be
reviewed. [Figure 10-6]
1. Parallel Procedure. When approaching the holding fix
from anywhere in sector (a), fly to the fix. Afterwards,
turn to a heading to parallel the holding course
outbound. Fly outbound for 1 minute, turn in the
direction of the holding pattern through more than
180°, and return to the holding fix or intercept the
holding course inbound.
2. Teardrop Procedure. When approaching the holding
fix from anywhere in sector (b), the teardrop entry
procedure would be to fly to the fix, turn outbound to
a heading for a 30° teardrop entry within the pattern
(on the holding side) for a period of 1 minute, then
turn in the direction of the holding pattern to intercept
the inbound holding course.
3. Direct Entry Procedure. When approaching the
holding fix from anywhere in sector (c), the direct
entry procedure would be to fly directly to the fix and
turn to follow the holding pattern.
A pilot should make all turns during entry and while holding at:
1. 3° per second, or
2. 30° bank angle, or
3. A bank angle provided by a flight director system.
Time Factors
The holding pattern entry time reported to ATC is the initial
time of arrival over the fix. Upon entering a holding pattern, the
initial outbound leg is flown for 1 minute at or below 14,000
feet MSL, and for 11⁄2 minutes above 14,000 feet MSL. Timing
for subsequent outbound legs should be adjusted as necessary
to achieve proper inbound leg time. The pilot should begin
outbound timing over or abeam the fix, whichever occurs later.
If the abeam position cannot be determined, start timing when
the turn to outbound is completed. [Figure 10-7]
Time leaving the holding fix must be known to ATC before
succeeding aircraft can be cleared to the vacated airspace.
Leave the holding fix:
1. When ATC issues either further clearance en route or
approach clearance;
2. As prescribed in 14 CFR part 91 (for IFR operations;
two-way radio communications failure, and
responsibility and authority of the pilot-in-command);
or
3. After the IFR flight plan has been cancelled, if the
aircraft is holding in VFR conditions.
DME Holding
The same entry and holding procedures apply to DME
holding, but distances (nautical miles) are used instead of
time values. The length of the outbound leg is specified by
the controller, and the end of this leg is determined by the
DME readout.
Approaches
Compliance With Published Standard Instrument
Approach Procedures
Compliance with the approach procedures shown on the
approach charts provides necessary navigation guidance
information for alignment with the final approach courses,
as well as obstruction clearance. Under certain conditions,
a course reversal maneuver or procedure turn may be
necessary. However, this procedure is not authorized when:
1. The symbol “NoPT” appears on the approach course
on the plan view of the approach chart.
2. Radar vectoring is provided to the final approach
course.
3. A holding pattern is published in lieu of a procedure
turn.
4. Executing a timed approach from a holding fix.
5. Otherwise directed by ATC.
Instrument Approaches to Civil Airports
Unless otherwise authorized, when an instrument letdown to
an airport is necessary, the pilot should use a standard IAP
prescribed for that airport. IAPs are depicted on IAP charts
and are found in the TPP.
ATC approach procedures depend upon the facilities available
at the terminal area, the type of instrument approach executed,
and the existing weather conditions. The ATC facilities,
NAVAIDs, and associated frequencies appropriate to each
standard instrument approach are given on the approach
chart. Individual charts are published for standard approach
procedures associated with the following types of facilities:
1. Nondirectional beacon (NDB)
2. Very-high frequency omnirange (VOR)
3. Very-high frequency omnirange with distance
measuring equipment (VORTAC or VOR/DME)
4. Localizer (LOC)
5. Instrument landing system (ILS)
6. Localizer-type directional aid (LDA)
7. Simplified directional facility (SDF)
8. Area navigation (RNAV)
9. Global positioning system (GPS)
An IAP can be flown in one of two ways: as a full approach
or with the assistance of radar vectors. When the IAP is flown
as a full approach, pilots conduct their own navigation using
the routes and altitudes depicted on the instrument approach
chart. A full approach allows the pilot to transition from
the en route phase, to the instrument approach, and then to
a landing with minimal assistance from ATC. This type of
procedure may be requested by the pilot but is most often
used in areas without radar coverage. A full approach also
provides the pilot with a means of completing an instrument
approach in the event of a communications failure.
When an approach is flown with the assistance of radar
vectors, ATC provides guidance in the form of headings and
altitudes, which position the aircraft to intercept the final
approach. From this point, the pilot resumes navigation,
intercepts the final approach course, and completes the
approach using the IAP chart. This is often a more expedient
method of flying the approach, as opposed to the full
approach, and allows ATC to sequence arriving traffic. A
pilot operating in radar contact can generally expect the
assistance of radar vectors to the final approach course.
Approach to Airport Without an Operating Control
Tower
Figure 10-8 shows an approach procedure at an airport
without an operating control tower. When approaching
such a facility, the pilot should monitor the AWOS/ASOS
if available for the latest weather conditions. When direct
communication between the pilot and controller is no
longer required, the ARTCC or approach controller issues a
clearance for an instrument approach and advises “change to
advisory frequency approved.” When the aircraft arrives on
a “cruise” clearance, ATC does not issue further clearance
for approach and landing.
If an approach clearance is required, ATC authorizes the pilots
to execute his or her choice of standard instrument approach
(if more than one is published for the airport) with the
Figure 10-8. Approach: an approach procedure at an airport without an operating control tower.
SE-4, 16 DEC 2010 to 13 JAN 2011
SE-4, 16 DEC 2010 to 13 JAN 2011
Figure 10-8. Monroeville, Alabama (MVC) VOR or GPS Rwy 3 Approach: An approach procedure at an airport without an operating
control tower.