6.departure-procedures-dp. Departure Procedures (DPs)
Departure Procedures (DPs) are preplanned instrument flight rule (IFR) procedures published in graphic and/or textual form that provide obstruction clearance from the terminal area to the appropriate en route structure. They are the IFR pilot's primary tool for transitioning safely from the airport environment to the en route phase of flight, and ATC expects pilots to fly them as published unless an alternate clearance is issued.
DPs exist for two principal reasons: to provide obstacle clearance for departing aircraft and to simplify clearance delivery by allowing controllers to issue a single procedure name rather than reading a long string of headings, altitudes, and fixes. The FAA categorizes DPs into two types:
- Obstacle Departure Procedures (ODPs) — Designed solely to provide obstruction clearance. Printed textually (and sometimes graphically) in the front of each Terminal Procedures Publication (TPP) volume. ODPs may be flown without ATC clearance unless an alternate departure procedure (SID, radar vector, or specific routing) has been assigned. Pilots are not required to accept an ODP, but if terrain or obstacles are a factor and no other procedure is assigned, flying the ODP is the recommended course of action.
- Standard Instrument Departures (SIDs) — ATC-requested procedures designed to expedite clearance delivery and traffic flow. SIDs are always issued by ATC and must be accepted by the pilot before being flown. If a pilot does not wish to use a SID, the phrase "No SIDs" should be entered in the remarks section of the IFR flight plan.
DPs are further subdivided into Pilot Navigation (Pilot Nav) DPs and Vector DPs. A Pilot Nav DP requires the pilot to navigate along the depicted route using onboard equipment (VOR, GPS, RNAV). A Vector DP relies on ATC radar vectors to a route or fix; the chart will show an "ATC" symbol or notation indicating that vectors will be provided.
Standard climb gradient. Unless a higher gradient is published, the FAA's standard climb gradient on a DP is 200 feet per nautical mile (ft/NM) to the published minimum IFR altitude. To convert ft/NM to a feet-per-minute climb rate:
Climb rate (ft/min) = (ground speed in knots ÷ 60) × required ft/NM
Example: At 120 knots ground speed with a required gradient of 350 ft/NM, the required climb rate is (120 ÷ 60) × 350 = 700 ft/min. The TPP includes a Rate of Climb Table in the front matter to help convert gradient to vertical speed quickly.
Diverse Vector Areas (DVAs). Where an airport has no published ODP or SID and terrain or obstacles preclude omnidirectional departures, ATC may establish a DVA, which permits radar vectors below the minimum vectoring altitude (MVA) immediately after departure. DVAs may also impose a non-standard climb gradient — pilots will be advised in the clearance.
Required pilot actions before departure. Per AIM 5-2-9 and good IFR practice, before accepting a DP the pilot must:
- Possess at least the textual description of the procedure.
- Determine whether the aircraft can meet any non-standard climb gradient specified.
- Verify that all required navigation equipment (e.g., DME, GPS, ADF) listed in the procedure notes is operational. Some DPs require GPS or RNAV 1; others have equipment notes such as "RADAR REQUIRED" or "DME REQUIRED."
- Brief the procedure: initial heading, climb-to altitude, expected altitude, transitions, lost communications procedure, and any climb-gradient or speed restrictions.
Climb gradient examples. A DP may read: "Climb runway heading to 1,500, then climbing left turn direct ABC VOR. Cross ABC at or above 5,000. Minimum climb 280 ft/NM to 4,000." The pilot must (1) maintain runway heading until 1,500 ft MSL, (2) achieve at least 280 ft/NM until passing 4,000, and (3) cross ABC at 5,000 or higher.
Lost communications on a DP. If two-way radio communications are lost while flying a DP, the pilot continues per the route and altitude assignments contained in the DP, transitioning to the lost-comm procedures of 14 CFR 91.185 (route: AVE-F; altitude: MEA).
Non-Part 95 obstacle assessment. ODPs are designed assuming the aircraft crosses the departure end of runway (DER) at or above 35 feet AGL, climbs straight on runway heading until reaching 400 feet AGL before any turns, and maintains the required climb gradient. Failure to meet these assumptions invalidates the procedure's obstacle protection.
In summary, DPs reduce pilot workload, standardize ATC communication, and — most importantly — keep aircraft clear of terrain and obstacles during the high-workload departure phase. Treat every IFR departure as a procedure to be briefed, even at familiar airports.