Aeronautical Information Manual (AIM), page 337

Index   336 -- Page 337 -- 338


Section 4. Arrival Procedures

5-4-1. Standard Terminal Arrival (STAR)

a. A STAR is an ATC coded IFR arrival route

established for application to arriving IFR aircraft

destined for certain airports. STARs simplify clear-

ance delivery procedures, and also facilitate

transition between en route and instrument approach

1. STAR procedures may have mandatory
speeds and/or crossing altitudes published. Other
STARs may have planning information depicted to
inform pilots what clearances or restrictions to
"expect." "Expect" altitudes/speeds are not consid-
ered STAR procedures crossing restrictions unless
verbally issued by ATC. Published speed restrictions
are independent of altitude restrictions and are
mandatory unless modified by ATC. Pilots should
plan to cross waypoints with a published speed
restriction, at the published speed, and should not
exceed this speed past the associated waypoint unless
authorized by ATC or a published note to do so.

The "expect" altitudes/speeds are published so that pilots
may have the information for planning purposes. These
altitudes/speeds must not be used in the event of lost
communications unless ATC has specifically advised the
pilot to expect these altitudes/speeds as part of a further

14 CFR Section 91.185(c)(2)(iii).

2. Pilots navigating on STAR procedures must
maintain last assigned altitude until receiving
authorization to descend so as to comply with all
published/issued restrictions. This authorization may
contain the phraseology "DESCEND VIA." If
vectored or cleared to deviate off of a STAR, pilots
must consider the STAR canceled, unless the
controller adds "expect to resume STAR;" pilots
should then be prepared to rejoin the STAR at a
subsequent fix or procedure leg. If a descent
clearance has been received that included a crossing
restriction, pilots should expect the controller to issue
an altitude to maintain.

(a) Clearance to "descend via" authorizes
pilots to:

(1) Descend at pilot's discretion to meet
published restrictions and laterally navigate on a

(2) When cleared to a waypoint depicted on

a STAR, to descend from a previously assigned alti-

tude at pilot's discretion to the altitude depicted at that


(3) Once established on the depicted ar-
rival, to descend and to meet all published or assigned
altitude and/or speed restrictions.
1. When otherwise cleared along a route or procedure that
contains published speed restrictions, the pilot must com-
ply with those speed restrictions independent of any
descend via clearance.
2. ATC anticipates pilots will begin adjusting speed the
minimum distance necessary prior to a published speed re-
striction so as to cross the waypoint/fix at the published
speed. Once at the published speed, ATC expects pilots will
maintain the published speed until additional adjustment
is required to comply with further published or ATC as-
signed speed restrictions or as required to ensure
compliance with 14 CFR Section 91.117.
3. The "descend via" is used in conjunction with STARs to
reduce phraseology by not requiring the controller to re-
state the altitude at the next waypoint/fix to which the pilot
has been cleared.

4. Air traffic will assign an altitude to cross the waypoint/
fix, if no altitude is depicted at the waypoint/fix, for aircraft
on a direct routing to a STAR. Air traffic must ensure
obstacle clearance when issuing a "descend via" instruc-

tion to the pilot.
5. Minimum en route altitudes (MEA) are not considered
restrictions; however, pilots must remain above all MEAs,
unless receiving an ATC instruction to descend below the
1. Lateral/routing clearance only.
"Cleared Tyler One arrival."
In Example 1, pilots are cleared to fly the lateral path of the
procedure. Compliance with any published speed restric-
tions is required. No descent is authorized.
2. Routing with assigned altitude.
"Cleared Tyler One arrival, descend and maintain
flight level two four zero."
"Cleared Tyler One arrival, descend at pilot's discre-
tion, maintain flight level two four zero."

Arrival Procedures 5-4-1

Page 337 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   336 -- Page 337 -- 338