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segment to the runway or missed approach point,
whichever occurs last. Side-step obstacle protection
is provided by increasing the width of the final
approach obstacle clearance area. Circling approach
protected areas are defined by the tangential
connection of arcs drawn from each runway end. The
arc radii distance differs by aircraft approach
category. Because of obstacles near the airport, a
portion of the circling area may be restricted by a
procedural note: e.g., “Circling NA E of
RWY 17−35.” Obstacle clearance is provided at the
published minimums for the pilot that makes a
straight-in approach, side-steps, circles, or executes
the missed approach. Missed approach obstacle
clearance requirements may dictate the published
minimums for the approach. (See FIG 5−4−20.)
AIM 2/17/05
5−4−42 Arrival Procedures
FIG 5−4−20
Final Approach Obstacle Clearance
CIRCLING APPROACH AREA RADII
CIRCLING APPROACH AREA
RADI (r) DEFINING SIZE
OF AREAS, VARY WITH THE
APPROACH CATEGORY
r
r
r
r
r
ABCDE
1.3
1.5
1.7
2.3
4.5
Approach Category Radius (Miles)
c. Straight-in Minimums are shown on the IAP
when the final approach course is within 30 degrees
of the runway alignment (15 degrees for GPS IAPs)
and a normal descent can be made from the IFR
altitude shown on the IAP to the runway surface.
When either the normal rate of descent or the runway
alignment factor of 30 degrees (15 degrees for GPS
IAPs) is exceeded, a straight-in minimum is not
published and a circling minimum applies. The fact
that a straight-in minimum is not published does not
preclude pilots from landing straight-in if they have
the active runway in sight and have sufficient time to
make a normal approach for landing. Under such
conditions and when ATC has cleared them for
landing on that runway, pilots are not expected to
circle even though only circling minimums are
published. If they desire to circle, they should advise
ATC.
d. Side-Step Maneuver Minimums. Landing
minimums for a side-step maneuver to the adjacent
runway will normally be higher than the minimums
to the primary runway.
e. Published Approach Minimums. Approach
minimums are published for different aircraft
categories and consist of a minimum altitude (DA,
DH, MDA) and required visibility. These minimums
are determined by applying the appropriate TERPS
criteria. When a fix is incorporated in a nonprecision
final segment, two sets of minimums may be
published: one for the pilot that is able to identify the
fix, and a second for the pilot that cannot. Two sets of
minimums may also be published when a second
altimeter source is used in the procedure. When a
nonprecision procedure incorporates both a stepdown
fix in the final segment and a second altimeter
source, two sets of minimums are published to
account for the stepdown fix and a note addresses
minimums for the second altimeter source.
2/17/05 AIM
Arrival Procedures 5−4−43
f. Circling Minimums. In some busy terminal
areas, ATC may not allow circling and circling
minimums will not be published. Published circling
minimums provide obstacle clearance when pilots
remain within the appropriate area of protection.
Pilots should remain at or above the circling altitude
until the aircraft is continuously in a position from
which a descent to a landing on the intended runway
can be made at a normal rate of descent using normal
maneuvers. Circling may require maneuvers at low
altitude, at low airspeed, and in marginal weather
conditions. Pilots must use sound judgment, have an
indepth knowledge of their capabilities, and fully
understand the aircraft performance to determine the
exact circling maneuver since weather, unique airport
design, and the aircraft position, altitude, and
airspeed must all be considered. The following basic
rules apply:
1. Maneuver the shortest path to the base or
downwind leg, as appropriate, considering existing
weather conditions. There is no restriction from
passing over the airport or other runways.
2. It should be recognized that circling
maneuvers may be made while VFR or other flying
is in progress at the airport. Standard left turns or
specific instruction from the controller for maneuvering
must be considered when circling to land.
3. At airports without a control tower, it may be
desirable to fly over the airport to observe wind and
turn indicators and other traffic which may be on the
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