AIM

8/15/19

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27

Arrival Procedures

miles from the fix. ATC must issue a straight-in
approach clearance when clearing an aircraft direct to
an IAF/IF with a procedure turn or hold

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in

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lieu of a

procedure turn, and ATC does not want the aircraft to
execute the course reversal.

NOTE

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Refer to 14 CFR 91.175 (i).

7.

RNAV aircraft may be issued a clearance

direct to the FAF that is also charted as an IAF, in
which case the pilot is expected to execute the
depicted procedure turn or hold-in-lieu of procedure
turn.  ATC will not issue a straight-in approach
clearance.  If the pilot desires a straight-in approach,
they must request vectors to the final approach course
outside of the FAF or fly a published “NoPT” route. 
When visual approaches are in use, ATC may clear an
aircraft direct to the FAF.

NOTE

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1.

In anticipation of a clearance by ATC to any fix pub-

lished on an instrument approach procedure, pilots of
RNAV aircraft are advised to select an appropriate IAF or
feeder fix when loading an instrument approach procedure
into the RNAV system.

2.

Selection of “Vectors-to-Final” or “Vectors” option for

an instrument approach may prevent approach fixes
located outside of the FAF from being loaded into an RNAV
system. Therefore, the selection of these options is
discouraged due to increased workload for pilots to
reprogram the navigation system.

f.

An RF leg is defined as a constant radius circular

path around a defined turn center that starts and
terminates at a fix. An RF leg may be published as
part of a procedure. Since not all aircraft have the
capability to fly these leg types, pilots are responsible
for knowing if they can conduct an RNAV approach
with an RF leg. Requirements for RF legs will be
indicated on the approach chart in the notes section or
at the applicable initial approach fix. Controllers will
clear RNAV-equipped aircraft for instrument ap-
proach procedures containing RF legs:

1.

Via published transitions, or

2.

In accordance with paragraph e6 above, and

3.

ATC will not clear aircraft direct to any

waypoint beginning or within an RF leg, and will not
assign fix/waypoint crossing speeds in excess of
charted speed restrictions.

EXAMPLE

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Controllers will not clear aircraft direct to THIRD because

that waypoint begins the RF leg, and aircraft cannot be
vectored or cleared to TURNN or vectored to intercept the
approach segment at any point between THIRD and
FORTH because this is the RF leg. (See FIG 5

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4

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15.)

g.

When necessary to cancel a previously issued

approach clearance, the controller will advise the
pilot “Cancel Approach Clearance” followed by any
additional instructions when applicable.

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7. Instrument Approach Procedures

a.

Aircraft approach category means a grouping of

aircraft based on a speed of V

REF

,

 if specified, or if

V

REF

 is not specified, 1.3 V

SO

 at the maximum

certified landing weight. V

REF

,

  V

SO

,

 and the

maximum certified landing weight are those values as
established for the aircraft by the certification
authority of the country of registry. A pilot must use
the minima corresponding to the category determined
during certification or higher. Helicopters may use
Category A minima. If it is necessary to operate at a
speed in excess of the upper limit of the speed range
for an aircraft’s category, the minimums for the
higher category must be used. For example, an
airplane which fits into Category B, but is circling to
land at a speed of 145 knots, must use the approach
Category D minimums. As an additional example, a
Category A airplane (or helicopter) which is
operating at 130 knots on a straight

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in approach must

use the approach Category C minimums. See the
following category limits:

1.

Category A: Speed less than 91 knots.

2.

Category B: Speed 91 knots or more but less

than 121 knots.

3.

Category C: Speed 121 knots or more but

less than 141 knots.

4.

Category D: Speed 141 knots or more but

less than 166 knots.

5.

Category E: Speed 166 knots or more.

NOTE

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V

REF

 in the above definition refers to the speed used in

establishing the approved landing distance under the
airworthiness regulations constituting the type certifica-
tion basis of the airplane, regardless of whether that speed
for a particular airplane is 1.3

V

SO,

 1.23

V

SR,

 or some

higher speed required for airplane controllability. This
speed, at the maximum certificated landing weight,
determines the lowest applicable approach category for
all approaches regardless of actual landing weight.

b.

When operating on an unpublished route or

while being radar vectored, the pilot, when an