AIM Text
- ATC may assign departure restrictions, clearance void times, hold for release, and release times, when necessary, to separate departures from other traffic or to restrict or regulate the departure flow. Departures from an airport without an operating control tower must be issued either a departure release (along with a release time and/or void time if applicable), or a hold for release.
- Clearance Void Times.A pilot may receive a clearance, when operating from an airport without a control tower, which contains a provision for the clearance to be void if not airborne by a specific time. A pilot who does not depart prior to the clearance void time must advise ATC as soon as possible of their intentions. ATC will normally advise the pilot of the time allotted to notify ATC that the aircraft did not depart prior to the clearance void time. This time cannot exceed 30 minutes. Failure of an aircraft to contact ATC within 30 minutes after the clearance void time will result in the aircraft being considered overdue and search and rescue procedures initiated.
- Hold for Release.ATC may issue “hold for release” instructions in a clearance to delay an aircraft's departure for traffic management reasons (i.e., weather, traffic volume, etc.). When ATC states in the clearance, “hold for release,” the pilot may not depart utilizing that IFR clearance until a release time or additional instructions are issued by ATC. In addition, ATC will include departure delay information in conjunction with “hold for release” instructions. The ATC instruction, “hold for release,” applies to the IFR clearance and does not prevent the pilot from departing under VFR. However, prior to takeoff the pilot should cancel the IFR flight plan and operate the transponder/ADS-B on the appropriate VFR code. An IFR clearance may not be available after departure.
- Release Times.A “release time” is a departure restriction issued to a pilot by ATC, specifying the earliest time an aircraft may depart. ATC will use “release times” in conjunction with traffic management procedures and/or to separate a departing aircraft from other traffic.
- Expect Departure Clearance Time (EDCT). The EDCT is the runway release time assigned to an aircraft included in traffic management programs. Aircraft are expected to depart no earlier than 5 minutes before, and no later than 5 minutes after the EDCT.
- If practical, pilots departing uncontrolled airports should obtain IFR clearances prior to becoming airborne when two‐way communications with the controlling ATC facility is available.
Source: FAA Aeronautical Information Manual · current edition · paragraph 5-2-7.
Research Notes
AIM 5-2-7 covers Abbreviated IFR Departure Clearance (Cleared as Filed) — the shortened format ATC uses when the clearance matches the filed flight plan.
The shortened format: "[Aircraft], cleared as filed, climb and maintain [altitude], expect [altitude] [time] after departure, contact Departure on [frequency], squawk [code]."
What 'as filed' means: The entire route from departure airport to destination is exactly what you filed. ATC will only state amendments ("cleared as filed except direct ZULU after BARMR").
What the pilot needs to verify: Their copy of the filed route matches what they have in the FMS/charts. If the controller says "cleared as filed" but the pilot loaded a different route into the GPS, they'll be off-track immediately.