3/21/24 

AIM 

b. 

The purpose of this information is to aid the pilot in planning arrival actions; however, it is not an ATC 

clearance or commitment and is subject to change. Pilots should bear in mind that fluctuating weather, shifting 

winds, blocked runway, etc., are conditions which may result in changes to approach information previously 

received. It is important that pilots advise ATC immediately they are unable to execute the approach ATC advised 

will be used, or if they prefer another type of approach. 

c. 

Aircraft destined to uncontrolled airports, which have automated weather data with broadcast capability, 

should monitor the ASOS/AWOS frequency to ascertain the current weather for the airport. The pilot must advise 

ATC when he/she has received the broadcast weather and state his/her intentions. 

NOTE

−

 

1. 

ASOS/AWOS should be set to provide one

−

minute broadcast weather updates at uncontrolled airports that are without 

weather broadcast capability by a human observer. 

2. 

Controllers will consider the long line disseminated weather from an automated weather system at an uncontrolled 

airport as trend and planning information only and will rely on the pilot for current weather information for the airport. If 
the pilot is unable to receive the current broadcast weather, the last long line disseminated weather will be issued to the pilot. 
When receiving IFR services, the pilot/aircraft operator is responsible for determining if weather/visibility is adequate for 
approach/landing. 

d. 

When making an IFR approach to an airport not served by a tower or FSS, after ATC advises “CHANGE 

TO ADVISORY FREQUENCY APPROVED” you should broadcast your intentions, including the type of 

approach being executed, your position, and when over the final approach fix inbound (nonprecision approach) 

or when over the outer marker or fix used in lieu of the outer marker inbound (precision approach). Continue 

to monitor the appropriate frequency (UNICOM, etc.) for reports from other pilots. 

5

−

4

−

5.  Instrument Approach Procedure (IAP) Charts 

a. 

14 CFR Section 91.175(a), Instrument approaches to civil airports, requires the use of SIAPs prescribed 

for the airport in 14 CFR Part 97 unless otherwise authorized by the Administrator (including ATC). If there are 

military procedures published at a civil airport, aircraft operating under 14 CFR Part 91 must use the civil 

procedure(s). Civil procedures are defined with “FAA” in parenthesis; e.g., (FAA), at the top, center of the 

procedure chart. DoD procedures are defined using the abbreviation of the applicable military service in 

parenthesis; e.g., (USAF), (USN), (USA). 14 CFR Section 91.175(g), Military airports, requires civil pilots 

flying into or out of military airports to comply with the IAPs and takeoff and landing minimums prescribed by 

the authority having jurisdiction at those airports. Unless an emergency exists, civil aircraft operating at military 

airports normally require advance authorization, commonly referred to as “Prior Permission Required” or 

“PPR.” Information on obtaining a PPR for a particular military airport can be found in the Chart Supplement. 

NOTE

−

 

Civil aircraft may conduct practice VFR approaches using DoD instrument approach procedures when approved by the air 

traffic controller. 

1. 

IAPs (standard and special, civil and military) are based on joint civil and military criteria contained in 

the U.S. Standard for TERPS. The design of IAPs based on criteria contained in TERPS, takes into account the 

interrelationship between airports, facilities, and the surrounding environment, terrain, obstacles, noise 

sensitivity, etc. Appropriate altitudes, courses, headings, distances, and other limitations are specified and, once 

approved, the procedures are published and distributed by government and commercial cartographers as 

instrument approach charts. 

2. 

Not all IAPs are published in chart form. Radar IAPs are established where requirements and facilities 

exist but they are printed in tabular form in appropriate U.S. Government Flight Information Publications. 

3. 

The navigation equipment required to join and fly an instrument approach procedure is indicated by the 

title of the procedure and notes on the chart. 

(a) 

Straight

−

in IAPs are identified by the navigational system providing the final approach guidance and 

the runway to which the approach is aligned (e.g., VOR RWY 13). Circling only approaches are identified by 

Arrival Procedures 

5

−

4

−

5