APPROACH CLEARANCE
The approach clearance provides guidance to a position
from where you can execute the approach, and it also
clears you to fly that approach. If only one approach procedure
exists, or if ATC authorizes you to execute the
approach procedure of your choice, the clearance may
be worded as simply as “… cleared for approach.” If
ATC wants to restrict you to a specific approach, the
controller names the approach in the clearance—for
example, “…cleared ILS Runway 35 Right approach.”
When the landing will be made on a runway that is not
aligned with the approach being flown, the controller
may issue a circling approach clearance, such as
“…cleared for VOR Runway 17 approach, circle to land
Runway 23.”
When cleared for an approach prior to reaching a holding
fix, ATC expects the pilot to continue to the holding
fix, along the feeder route associated with the fix, and
then to the IAF. If a feeder route to an IAF begins at a
fix located along the route of flight prior to reaching
the holding fix, and clearance for an approach is
issued, the pilot should commence the approach via the
published feeder route. The pilot is expected to commence
the approach in a similar manner at the IAF, if
the IAF is located along the route to the holding fix.
ATC also may clear an aircraft directly to the IAF by
using language such as “direct” or “proceed direct.”
Controllers normally identify an approach by its published
name, even if some component of the approach
aid (such as the glide slope of an ILS) is inoperative or
unreliable. The controller uses the name of the
approach as published but advises the aircraft when
issuing the approach clearance that the component is
unusable.
PRESENT POSITION DIRECT
In addition to using National Aeronautical Charting
Office (NACO) high and low altitude en route charts as
resources for your arrival, NACO area charts can be
helpful as a planning aid for situational awareness.
Many pilots find the area chart helpful in locating a
depicted fix after ATC clears them to proceed to a fix
and hold, especially at unfamiliar airports.
Looking at Figures 4-6, and 4-7 on page 4-8, assume
you are V295 northbound en route to Palm Beach
International Airport. You are en route on the airway
when the controller clears you present position direct to
the outer marker compass locator and for the instrument
landing system (ILS) approach. There is no transition
authorized or charted between your present position and
the approach facility. There is no minimum altitude published
for the route you are about to travel.
In Figure 4-6, you are just north of HEATT Intersection
at 5,000 feet when the approach controller states,
“Citation 9724J, 2 miles from HEATT, cleared present
position direct RUBIN, cleared for the Palm Beach ILS
Runway 9L Approach, contact Palm Beach Tower on
119.1 established inbound.” With no minimum altitude
published from that point to the RUBIN beacon, you
should maintain the last assigned altitude until you reach
the IAF (that’s the fix, not the facility). Then, in Figure
4-7 on page 4-8, after passing the beacon outbound,
commence your descent to 2,000 feet for the course
reversal.
The ILS procedure relies heavily on the controller’s
recognition of the restriction upon you to maintain
your last assigned altitude until “established” on a published
segment of the approach. Refer to Appendix B,
“Staying Within Protected Airspace,” for a comprehensive
discussion of “established.” Prior to issuing a
clearance for the approach, the controller usually
assigns the pilot an altitude compatible with glide slope
intercept.
RADAR VECTORS TO FINAL APPROACH COURSE
Arriving aircraft usually are vectored to intercept the
final approach course, except with vectors for a visual
approach, at least 2 NM outside the approach gate unless
one of the following exists:
1. When the reported ceiling is at least 500 feet above
the minimum vectoring altitude or minimum IFR
altitude and the visibility is at least 3 NM (report
may be a pilot report if no weather is reported
for the airport), aircraft may be vectored to intercept
the final approach course closer than 2 NM
outside the approach gate but no closer than the
approach gate.
2. If specifically requested by a pilot, ATC may
vector aircraft to intercept the final approach
course inside the approach gate but no closer than
the FAF.
For a precision approach, aircraft are vectored at an altitude
that is not above the glide slope/glidepath or below
the minimum glide slope intercept altitude specified on
the approach procedure chart. For a nonprecision
approach, aircraft are vectored at an altitude that allows
descent in accordance with the published procedure.
When a vector will take the aircraft across the final
approach course, pilots are informed by ATC and the
reason for the action is stated. In the event that ATC is
not able to inform the aircraft, the pilot is not expected
to turn inbound on the final approach course unless an
approach clearance has been issued. An example of
ATC phraseology in this case is, “…expect vectors
across final for spacing.”
The following ATC arrival instructions are issued to
an IFR aircraft before it reaches the approach gate:
1. Position relative to a fix on the final approach
course. If none is portrayed on the controller’s
radar display or if none is prescribed in the instrument
approach procedure, ATC issues position
information relative to the airport or relative to
the navigation aid that provides final approach
guidance.
2. Vector to intercept the final approach course if
required.
3. Approach clearance except when conducting a
radar approach. ATC issues the approach clearance
only after the aircraft is established on a segment
of a published route or instrument approach procedure,
or in the following examples as depicted in
Figure 4-8 on page 4-9.
Aircraft 1 was vectored to the final approach course but
clearance was withheld. It is now at 4,000 feet and
established on a segment of the instrument approach
procedure. “Seven miles from X-RAY. Cleared ILS runway
three six approach.”
Aircraft 2 is being vectored
to a published
segment of the final
approach course, 4 NM
from LIMA at 2,000 feet.
The minimum vectoring
altitude for this area is
2,000 feet. “Four miles
from LIMA. Turn right
heading three four zero.
Maintain two thousand
until established on the
localizer. Cleared ILS
runway three six
approach.”
There are many times
when it is desirable to
position an aircraft onto
the final approach course
prior to a published,
charted segment of an
instrument approach procedure
(IAP). Sometimes
IAPs have no initial segment
and require vectors.
“RADAR REQUIRED”
will be charted in the
planview. Sometimes a
route will intersect an
extended final approach
course making a long
intercept desirable.
When ATC issues a vector
or clearance to the
final approach course
beyond the published
segment, controllers
assign an altitude to
maintain until the aircraft
is established on a segment
of a published route
or IAP. This ensures that
both the pilot and controller
know precisely
what altitude is to be
flown and precisely
where descent to appropriate
minimum altitudes
or step-down altitudes can begin.
Most aircraft are vectored onto a localizer or final
approach course between an intermediate fix and the
approach gate. These aircraft normally are told to maintain
an altitude until established on a segment of the
approach.
When an aircraft is assigned a route that will establish the
aircraft on a published segment of an approach, the controller
must issue an altitude to maintain until the aircraft
is established on a published segment of the approach.
Aircraft 4 is established on the final approach course
beyond the approach segments, 8 NM from Alpha at
6,000 feet. The minimum vectoring altitude for this area is 4,000 feet. “Eight miles from Alpha. Cross Alpha at
or above four thousand. Cleared ILS runway three six
approach.”
If an aircraft is not established on a segment of a published
approach and is not conducting a radar approach,
ATC will assign an altitude to maintain until the aircraft
is established on a segment of a published route
or instrument approach procedure, as depicted in
Figure 4-9.
The aircraft is being vectored to a published segment of
the ILS final approach course, 3 NM from Alpha at 4,000 feet. The minimum vectoring altitude for this area
is 4,000 feet. “Three miles from Alpha. Turn left heading
two one zero. Maintain four thousand until established
on the localizer. Cleared ILS runway one eight
approach.”
The ATC assigned altitude ensures IFR obstruction
clearance from the point at which the approach clearance
is issued until established on a segment of a
published route or instrument approach procedure.
ATC tries to make frequency changes prior to passing
the FAF, although when radar is used to establish the
FAF, ATC informs the pilot to contact the tower on the
local control frequency after being advised that the aircraft
is over the fix. For example, “Three miles from
final approach fix. Turn left heading zero one zero.
Maintain two thousand until established on the localizer.
Cleared ILS runway three six approach. I will
advise when over the fix.”
“Over final approach fix. Contact tower one one eight
point one.”
Where a terminal arrival area (TAA) has been established
to support RNAV approaches, as depicted in Figure 4-10, ATC informs the aircraft of its position
relative to the appropriate IAF and issues the approach
clearance, as shown in the following examples:
Aircraft 1 is in the straight-in area of the TAA. “Seven
miles from CENTR, Cleared RNAV Runway One Eight
Approach.’’
Aircraft 2 is in the left base area of the TAA. “Fifteen
miles from LEFTT, Cleared RNAV Runway One Eight
Approach.’’
Aircraft 3 is in the right base area of the TAA. “Four
miles from WRITE, Cleared RNAV Runway One Eight
Approach.”
IFR en route descent procedures should include a
review of minimum, maximum, mandatory, and recommended
altitudes that normally precede the fix or
NAVAID facility to which they apply. The initial descent
gradient for a low altitude instrument approach procedure
does not exceed 500 feet per NM (approximately 5
degrees), and for a high altitude approach, the maximum allowable initial gradient is 1,000 feet per NM
(approximately 10 degrees).
Remember during arrivals, when cleared for an instrument
approach, maintain the last assigned altitude until
you are established on a published segment of the
approach, or on a segment of a published route. If no
altitude is assigned with the approach clearance and you
are already on a published segment, you can descend to
its minimum altitude.
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