AIM Text
- Pilot.
- Advises ATC any time cruising airspeed varies plus or minus 5 percent or 10 knots, whichever is greater, from that given in the flight plan.
- Complies with speed adjustments from ATC unless:
- The minimum or maximum safe airspeed for any particular operation is greater or less than the requested airspeed. In such cases, advises ATC.
- Operating at or above 10,000 feet MSL on an ATC assigned SPEED ADJUSTMENT of more than 250 knots IAS and subsequent clearance is received for descent below 10,000 feet MSL. In such cases, pilots are expected to comply with 14 CFR section 91.117(a).
- When complying with speed adjustment assignments, maintains an indicated airspeed within plus or minus 10 knots or 0.02 Mach number of the specified speed.
- Controller.
- Assigns speed adjustments to aircraft when necessary but not as a substitute for good vectoring technique.
- Adheres to the restrictions published in FAA Order JO 7110.65, Air Traffic Control, as to when speed adjustment procedures may be applied.
- Avoids speed adjustments requiring alternate decreases and increases.
- Assigns speed adjustments to a specified IAS (KNOTS)/Mach number or to increase or decrease speed using increments of 5 knots or multiples thereof.
- Terminates ATC-assigned speed adjustments when no longer required by issuing further instructions to pilots in the following manner:
- Advises pilots to “resume normal speed” when the aircraft is on a heading, random routing, charted procedure, or route without published speed restrictions.
- Instructs pilots to “comply with speed restrictions” when the aircraft is joining or resuming a charted procedure or route with published speed restrictions.
- Instructs pilots to “resume published speed” when aircraft are cleared via a charted instrument flight procedure that contains published speed restrictions.
- Advises aircraft to “delete speed restrictions” when ATC assigned or published speed restrictions on a charted procedure are no longer required.
- Clears pilots for approach without restating previously issued speed adjustments.
- Gives due consideration to aircraft capabilities to reduce speed while descending.
- Does not assign speed adjustments to aircraft at or above FL 390 without pilot consent.
Source: FAA Aeronautical Information Manual · current edition · paragraph 5-5-9.
Research Notes
AIM 5-5-9 covers Holding — the standard maneuver to delay an aircraft within a defined airspace pattern.
Holding pattern structure:
- Standard hold: Right turns (clockwise)
- Non-standard hold: Left turns (counterclockwise) — published or assigned
- Leg length: 1 minute (below 14,000 MSL) or 1.5 minutes (above 14,000 MSL)
- Speed: 200 KIAS max in some holds; 230 KIAS above 14,000; 265 KIAS above 14,000 in some holds
The three holding entries:
- Direct entry: Cross the fix, turn to the outbound leg, fly the standard pattern. Used when approaching from the inbound direction.
- Teardrop entry: Cross the fix, turn to a 30°-offset heading outbound, fly outbound for 1 minute, then turn back to the inbound course. Used for certain approach angles.
- Parallel entry: Cross the fix, turn to parallel the inbound course (but outbound direction), fly outbound 1 minute, turn 180° to intercept the inbound course. Used for parallel approach angles.
Holding instructions ATC may issue:
- "Hold east of [fix] on [airway] V[number]"
- "Hold as published"
- "Expect further clearance at [time]"
- "Maintain [altitude] in the hold"
Reference: AIM 5-3 (Enroute Procedures); FAA-H-8083-16 Chapter 3; AIM 5-5-9.