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AIM

10/12/17

5−4−55

Arrival Procedures

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 step-

down 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.

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minimums will not be published.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 maneuver-

ing 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

runway or flying in the vicinity of the airport.

REFERENCE−

AC 90−66A, Recommended Standards Traffic patterns for Aeronautical

Operations at Airports without Operating Control Towers.

4. The missed approach point (MAP) varies

depending upon the approach flown. For vertically

guided approaches, the MAP is at the decision

altitude/decision height. Non−vertically guided and

circling procedures share the same MAP and the pilot

determines this MAP by timing from the final

approach fix, by a fix, a NAVAID, or a waypoint.

Circling from a GLS, an ILS without a localizer line

of minima or an RNAV (GPS) approach without an

LNAV line of minima is prohibited.

g. Instrument Approach at a Military Field.

When instrument approaches are conducted by civil

aircraft at military airports, they must be conducted in

accordance with the procedures and minimums

approved by the military agency having jurisdiction

over the airport.

3/29/18

AIM