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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