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AIM

10/12/17

4

−4−9

ATC Clearances and Aircraft Separation

speed, ATC expects pilots will maintain the published
speed until additional adjustment is required to comply
with further published or ATC assigned speed restrictions
or as required to ensure compliance with 14 CFR
Section 91.117.

EXAMPLE

(An aircraft is flying a SID/STAR with published speed
restrictions. ATC issues a speed adjustment and instructs
the aircraft where the adjustment ends): “Maintain two two
zero knots until BALTR then resume published speed.”

NOTE

The ATC assigned speed assignment of two two zero knots
would apply until BALTR. The aircraft would then comply
with the published speed restrictions.

4.

Advise the pilot to “delete speed restrictions”

when either ATC assigned or published speed
restrictions on a charted procedure are no longer
required.

EXAMPLE

(An aircraft is flying a SID with published speed
restrictions designed to prevent aircraft overtake on
departure. ATC determines there is no conflicting traffic
and deletes the speed restriction): “Delete speed
restrictions.”

NOTE

When deleting published restrictions, ATC must ensure
obstacle clearance until aircraft are established on a route
where no published restrictions apply. This does not relieve
the pilot of those speed restrictions which are applicable to
14 CFR Section 91.117.

5.

Instruct the pilot to “climb via” or “descend

via.” A climb via or descend via clearance cancels any
previously issued speed restrictions and, once
established on the depicted departure or arrival, to
climb or descend, and to meet all published or
assigned altitude and/or speed restrictions.

EXAMPLE

1. (An aircraft is flying a SID with published speed
restrictions. ATC has issued a speed restriction of 250 knots
for spacing. ATC determines that spacing between aircraft
is adequate and desires the aircraft to comply with
published restrictions): “United 436, Climb via SID.”

2. (An aircraft is established on a STAR. ATC must slow an
aircraft for the purposes of spacing and assigns it a speed
of 280 knots. When spacing is adequate, ATC deletes the
speed restriction and desires that the aircraft comply with
all published restrictions on the STAR): “Gulfstream two
three papa echo, descend via the TYLER One arrival.”

NOTE

1. In example 1, when ATC issues a “Climb via SID”
clearance, it deletes any previously issued speed and/or

altitude restrictions. The pilot should then vertically
navigate to comply with all speed and/or altitude
restrictions published on the SID.

2. In example 2, when ATC issues a “Descend via <STAR
name> arrival,” ATC has canceled any previously issued
speed and/or altitude restrictions. The pilot should
vertically navigate to comply with all speed and/or altitude
restrictions published on the STAR.

CAUTION

When descending on a STAR, pilots should not speed up
excessively beyond the previously issued speed. Otherwise,
adequate spacing between aircraft descending on the STAR
that was established by ATC with the previous restriction
may be lost.

g.

Approach clearances supersede any prior speed

adjustment assignments, and pilots are expected to
make their own speed adjustments as necessary to
complete the approach. However, under certain
circumstances, it may be necessary for ATC to issue
further speed adjustments after approach clearance is
issued to maintain separation between successive
arrivals. Under such circumstances, previously
issued speed adjustments will be restated if that speed
is to be maintained or additional speed adjustments
are requested. Speed adjustments should not be
assigned inside the final approach fix on final or a
point 5 miles from the runway, whichever is closer to
the runway.

h.

The pilots retain the prerogative of rejecting the

application of speed adjustment by ATC if the
minimum safe airspeed for any particular operation is
greater than the speed adjustment.

NOTE

In such cases, pilots are expected to advise ATC of the
speed that will be used.

i.

Pilots are reminded that they are responsible for

rejecting the application of speed adjustment by ATC
if, in their opinion, it will cause them to exceed the
maximum indicated airspeed prescribed by 14 CFR
Section 91.117(a), (c) and (d). IN SUCH CASES,
THE PILOT IS EXPECTED TO SO INFORM ATC.
Pilots operating at or above 10,000 feet MSL who are
issued speed adjustments which exceed 250 knots
IAS and are subsequently cleared below 10,000 feet
MSL are expected to comply with 14 CFR
Section 91.117(a).

j.

Speed restrictions of 250 knots do not apply to

U.S. registered aircraft operating beyond 12 nautical
miles from the coastline within the U.S. Flight