Learn ATC / Approach control

Approach speed control: which aircraft do you slow first?

August 1, 2026 · FAA arrival sequencing · JO 7110.65BB 5-7-1 through 5-7-4

TL;DR — BUILD THE GAP BEFORE FINAL

Decide where the spacing must exist, then make the smallest useful speed change early enough to work. In an in-trail compression, reduce the trailing aircraft first or increase the leader first. Restate an assigned speed with the approach clearance if it must continue, and do not assign one inside the FAF on final or five miles from the runway—whichever point is closer to the runway.

Speed control is not about making every datablock show the same number. It is a spacing tool. A good instruction creates the interval at a chosen point while still leaving the crew enough distance to configure and fly a stable approach. A late reduction may look decisive on the scope but achieve almost nothing before the aircraft reaches final.

Start with the interval, not the speed

FAA JO 7110.65 5-7-1 tells controllers to determine the required interval and the point where it must be achieved. Only then should a speed be selected. Aircraft do not change speed instantly: altitude, configuration and current speed all affect how much distance the change needs.

In an in-trail sequence that is compressing, the FAA gives two first choices:

Reduce the trailing aircraft first, so it stops gaining on the leader.
Increase the leading aircraft first, if it can accept the higher speed.

That does not mean “always slow number two.” If the leader is already near its practical approach speed, increasing it may be unrealistic. If the trailer is still clean and far from the runway, a modest early reduction may be the cleaner solution. The traffic picture and aircraft capabilities decide which option is useful.

The important question is not “who is faster?” but “will the required interval exist at the final, runway or wake-separation point?”

Use specific, readable phraseology

Current JO 7110.65BB expresses assigned airspeeds as indicated airspeed. Below FL240, controllers use five-knot increments. A pilot complying with an assigned or published speed is expected to remain within plus or minus 10 knots.

Controller intent	Phraseology example
Assign one value	“Delta three twenty one, reduce speed to one seven zero.”
Preserve flexibility above a floor	“Maintain one eight zero knots or greater.”
Cap the speed	“Do not exceed one eight zero knots.”
Use the fastest practical value	“Maintain maximum forward speed.”
Use the slowest practical value	“Maintain slowest practical speed.”
Change by an amount	“Reduce speed twenty knots.”

A specific value is easier to predict than “best forward speed,” but the practical phrases are useful while a broad sequence is still forming. As the picture tightens, replace them with a value when exact spacing requires one.

Know the recommended arrival minima

JO 7110.65 5-7-3 provides recommended minimum assignments. Lower speeds can be used when there is an operational advantage, and the pilot must advise if unable. These are controller speed-control minima—not a substitute for aircraft limitations, charted restrictions or the pilot's safe approach speed.

Arrival below 10,000 ft	More than 20 flying miles	Within 20 flying miles
Turbojet	Normally not below 210 kt	Normally not below 170 kt
Propeller / turboprop	Normally not below 200 kt	Normally not below 150 kt

Flying miles are not straight-line miles. An aircraft on a long downwind may be geographically close to the airport while still having more than 20 miles left along its expected flight path.

Do not carry the restriction too far

ATC must not assign a speed adjustment to an aircraft in a holding pattern, nor inside the final approach fix on final or a point five miles from the runway, whichever is closer to the runway. The rule is a cutoff for assigning speed—not a target point for finally solving the sequence.

By that stage, the aircraft needs room to configure and fly the approach. Build the interval on downwind, base or the earlier part of the arrival. On final, monitor what the earlier plan produced instead of alternating speed reductions and increases.

An approach clearance cancels the old assignment

An approach clearance cancels previously assigned speeds. If the assigned speed is still required after the approach clearance, restate it in the same transmission or issue a new adjustment when permitted:

APPROACH — SPEED MUST CONTINUE “Delta three twenty one, maintain one seven zero knots until SAYAE. Four miles from SAYAE, turn left heading three zero zero. Maintain three thousand until established. Cleared ILS runway two seven approach.”

If the speed is not restated, the pilot is expected to adjust as necessary to complete the approach. This is a common readback trap: a speed issued two minutes ago may still be visible in the controller's plan but no longer be part of the clearance.

Published speed and assigned speed are different layers

STARs may already contain published speed restrictions. When ATC adds an unpublished speed, make clear where it starts or ends. Use the matching termination phrase:

“Resume normal speed” ends an ATC-assigned speed where no underlying published restriction applies.
“Resume published speed” ends the unpublished assignment and returns the aircraft to subsequent charted speed restrictions.
“Comply with speed restrictions” requires the charted restrictions on the procedure.
“Delete speed restrictions” removes assigned and published restrictions, but never removes regulatory limits such as 14 CFR 91.117.

APPROACH — RETURN TO THE STAR “American four eighty two, maintain two two zero knots until BALTR, then resume published speed.”

Speed and descent need an order

Turbojets can struggle to descend and slow simultaneously. When both actions matter, say which one comes first. The word “then” makes the priority explicit:

SLOW FIRST “Southwest eight fifty, reduce speed to two one zero, then descend and maintain six thousand.”

DESCEND FIRST “Southwest eight fifty, descend and maintain six thousand, then reduce speed to two one zero.”

Choose the order that protects the plan. If spacing is already collapsing, speed may come first. If altitude is the immediate constraint and the interval is stable, descent may come first. Avoid issuing both without an order and leaving the pilot to guess which result ATC needs first.

Readbacks and “unable” are operational information

Check the callsign, exact speed, any “or greater” or “do not exceed” qualifier, and the fix where the restriction ends. If the pilot says “unable” or reports a higher minimum safe speed, rebuild the sequence; the pilot retains the prerogative to reject an excessive or operationally unsuitable adjustment.

PILOT CANNOT ACCEPT Pilot: “Delta three twenty one, unable one five zero, minimum one seven zero.”
ATC: “Delta three twenty one, maintain one seven zero knots.”

The correction is not always another speed. A vector, a longer downwind, a different landing order or a go-around may be the safer way to recover the interval.

Common controller mistakes

Waiting for the targets to touch. A speed change needs time and distance to affect spacing.
Slowing the leader while the trailer stays fast. That increases compression unless there is another part of the plan.
Changing the same aircraft repeatedly. Alternating reductions and increases creates workload and an unstable profile.
Forgetting that the approach clearance canceled the old speed. Restate the speed if it must continue.
Assigning speed too deep on final. The FAA cutoff is a limit, not a planning technique.
Using “resume normal speed” on a STAR with published restrictions. Choose the termination phrase that matches the underlying procedure.
Treating “unable” as bad compliance. It is new information about what the aircraft can safely do; issue a workable alternative.

A five-minute Approach drill

Start the free guided Radar shift or an APP/DEP session at KSAN.
Find the fastest trailing arrival before the gap becomes critical.
Assign one specific speed and watch whether the spacing trend stabilizes.
Issue the approach clearance and deliberately restate—or release—the speed.
Complete the Tower handoff, then review Sequencing and Efficiency in the debrief.

Primary references: FAA Order JO 7110.65BB, Chapter 5 Section 7 (application, methods, minima and termination), Aeronautical Information Manual 4-4-12 (pilot use of speed adjustments), and the FAA Pilot/Controller Glossary (speed adjustment). The current online order is effective July 9, 2026. Always use current publications, charts and facility directives.

Practise speed control on a live scope

The free Radar session puts multiple arrivals on the KSAN scope. Assign speeds, watch the spacing develop, clear the approach and complete the Tower handoff with spoken pilot readbacks.

START RADAR TRAINING