Standard Instrument Departure Procedures



Figure 1: Rate of Climb Table
Rate of Climb Table

Introduction:

  • Standard Instrument Departure Procedures (SIDs) are preplanned air traffic control (ATC) instrument flight rule (IFR) procedures which provide obstruction clearance from the terminal area to the appropriate en route structure
    • These procedures ensure a safe and expeditious climb out from an airport and to provide separation between aircraft to ensure safe transition
  • Issued primarily to provide obstruction clearance but secondary to reduce controller workload and support noise abatement programs
  • ATC clearance must be received prior to flying a SID
  • Pilots operating under 14 CFR Part 91 are strongly encouraged to file and fly a DP at night, during marginal Visual Meteorological Conditions (VMC) and Instrument Meteorological Conditions (IMC), when one is available
  • Booklets are available from AeroNav

Restrictions/Limitations:

  • Departure Procedures assume the pilot will cross the departure end of the runway at least 35' above the runway and climbing to 400' above the departure end elevation before making initial turn and then maintaining a standard 200' per NM conforming to the departure altitude limits
    • It is important that you are aware if your aircraft can perform to the restrictions on the DP
    • To calculate climb rate required (feet per minute) to meet or exceed the climb gradient (feet per nautical mile) you can either calculate it manually or use the chart on the back of the terminal approach plate publication
    • Take your ground speed in nautical miles per hour, divide by 60 minutes per hour, and multiply by the climb gradient in feet per nautical mile
  • These procedures are subject to change via the Notice to Airmen system which must always be checked as part of pre-flight
  • Primarily issued to provide guaranteed obstacle clearance, secondary to increase efficiency and reduce communications
  • Responsibility to avoid obstacles rests on the pilot
  • If the pilot does not possess a DP or does not wish to use one (due to gradient, equipment required, or other reason), he/she is expected to advise ATC
    • This may be accomplished by stating "NO DP" in the remarks section of the flight plan or by verbally advising ATC, but will likely result in a delay or deviation for departure
    • Pilots operating under Part 91, whether IFR rated or not, are strongly encouraged to use the ODP system and SIDs in marginal VFR conditions and at night when operating VFR
  • Locations with airport traffic control service, when necessary, specifies direction to take off, turn, or initial heading
  • Locations without airport traffic control service, but within class E surface area, when necessary to specify direction of takeoff, turn, or initial heading to be flown, obtains pilot concurrence that the procedure will allow the pilot to comply with local traffic patterns, terrain, and obstruction avoidance

Types of Terminal Instrument Procedures (TERPS):

  • There are multiple ways to define a safe area from the runway up to the airway/en-route structure
  • Two main types of printed departures:
    • Obstacle Departure Procedures (ODPs), printed either textually or graphically, and;
    • Standard Instrument Departures (SIDs), always printed graphically
  • All are initially based on the runway centerline, extended a minimum of 2 NM past the Departure end of the runway (DER) and provide for a climb to 400' above airport elevation or higher prior to any turn requirement
    1. The Diverse (RADAR) Departure:
      • Used where there is no published SID, or pilot desires to proceed directly to first point on route of flight
      • Says a pilot can climb to 400' above the runway and then turn in any direction (or turn as assigned by ATC) to climb and join the en-route structure
      • This departure capability, for the selected runway, is indicated by the absence of any other Obstacle Departure Procedure (ODP)
      • In-close obstacles may be published for a diverse runway or indicated by 300-1 visibility minimums
      • Enter the NAVAID or intersection that will establish you on your route as the first entry in the "ROUTE-OF-FLIGHT" section of the flight plan
      • Must have a note in the remarks section stating "request radar departure"
      • Remember you are only requesting flight advisory services from ATC, not vectors, but they can be provided if desired
    2. Obstacle DPs (ODPs):
      • ODPs may be flown without ATC clearance unless a specific other clearance was issued
      • If an obstacle penetrates what is called the 40:1 obstacle identification surface (OIS), then the procedure will either have:
        • A steeper climb gradient
        • Increased takeoff minima
        • Design or published a specific route
        • A combination of all
      • The 40:1 OIS begins at the departure end of the runway and slopes upward at 152' per NM until reaching minimum IFR altitude or entering the en-route structure
        • The area is limited to 25 NM in non-mountainous areas
        • The area is limited to 46 NM in mountainous areas
        • The pilot is then responsible for his own navigation on an assigned altitude or MEA/MOCA
      • Obstacle that cannot be cleared due to excessive climb gradient requirements will be depicted with a note about them
      • Textual Obstacle Departure Procedures (ODPs):
        • Designed to control departures to avoid obstacles or terrain in the terminal area
        • Only one procedure is published for a runway and the designer will try to maintain the default 200 feet per mile gradient or the lowest gradient possible
        • Many of these departures direct a pilot to a point from which diverse flight to the en-route structure can commence
        • Gradients, ceiling and visibility values, and close-in obstacles may also be published
        • The textual ODP will only be assigned when required for traffic separation purposes by ATC and reads, "Depart via the [airport name] [runway number] departure procedure"
        • If not issued, the Part 91, military and public service pilot doesn't have to fly the ODP, even in IMC conditions
        • Unless you have a good reason for creating your own departure, you'll want to stick to the ODP because it was built for a reason
        • The textual ODP existence is indicated by the (T) symbol on NACO plates and appears on the airport page of Jeppesen plates
        • Listed by city and airport in the IFR Takeoff Minimums and DPs section of the TPP
      • Graphic Obstacle Departures (ODPs):
        • Promulgated when the textual ODP would be too long or confusing
        • Graphic ODPs titles include "OBSTACLE"
        • The graphic ODPs may be issued by name in an IFR clearance
    3. The Standard Instrument Departure (SID):
      • Graphics created when traffic density warrants a high level of coordination to reduce pilot and controller workload
      • The SID maybe issued by name in an IFR clearance or filed by the pilot
      • The SID may originate from a runway that also meets diverse criteria or possesses a textual ODP
      • In-close obstacles may also be annotated on SIDs
      • Designed to ease departures from a congested area or support noise abatement
      • Always printed graphically
      • Approved ATC departure route clearance required in the event of radio failure
      • A period (.) after a sentence means you will not proceed any further until you have accomplished this instruction
    4. The Diverse Vector Area (DVA):
      • Occurs at airports with high traffic density where terrain and obstacles allow flexibility in departure routings
      • The DVA may originate from the same runway that has a textual ODP or SID. A runway that meets diverse departure criteria is a 360° DVA for the controllers
      • DVAs can have climb gradients greater than 200'/nm, but that should be issued with the IFR clearance
      • Only the controller knows the existence of a DVA
      • So, if you are issued a heading that does not mimic an initial SID or ODP routing from the DER and terrain or obstacles are a worry, query ATC if there is a DVA for your departure
      • If no DVA exists, consider advising ATC you'll fly the ODP prior to assuming the issued heading

Departure Categories:

  • Pilot Nav:
    • Consists of pre-published routes that supply headings, altitudes, and reporting points for the transition from takeoff to the en-route structure
    • Required a minimum of controller time and sorts departing aircraft by initial route
      • Initial vectoring may be required
      • Leave departure (heavy line) route at assigned transition points
      • Departure transitions (lighter line) at assigned route
    • The DP must be discontinued to accommodate weather or traffic conditions
    • Amendments may be issued as required
    • Card is divided into a pictorial section and a text description
  • Vector:
    • Radar vectors will be provided to a series of points
      • Same as requesting radar departure
    • More flexible than a pilot nav SID for things like traffic weather or temporary restrictions
    • More common at civilian airfields
    • More labor-intensive for the controller and the pilot repeating all altitudes, headings, and altimeter settings
    • Altitude deviations do not alleviate the pilot's responsibility to fly the route
    • Card is divided into a pictorial section and a text description

Changes to Clearance:

  • If you accept a SID as part of your clearance, comply with all specified routings, altitudes, and specific restrictions
    • SIDs must be followed regardless of weather conditions, unless a deviation is approved by ATC
  • Consider SID canceled if aircraft is vectored or cleared off SID-specified course, unless ATC adds "expect to resume SID" or otherwise indicates the deviation is temporary
  • If ATS desires to reinstate a canceled SID, departure must state the portion of routing that applies and restate altitude restrictions
  • If an altitude to maintain is changed or restated, either prior to or after departure, you can climb immediately to that altitude unless ATC states that altitude restriction remains in effect
    • The SID path-over-the-ground must still be followed even though a climb to higher altitude has commenced
  • If canceled, departure control must indicate portion of SID that still applies and must restate altitude restrictions

Procedure:

  1. File the flight plan
  2. Place your clearance on request with FSS
  3. Copy and read back entire clearance from ATC
    • UHF: "[place] clearance delivery, [call sign], IFR to [destination], clearance on request"
  4. SQUAWK assigned code
    • UHF: "[place] clearance, [call sign], ready to copy"
    • UHF: "[place] ground, [call sign] at [parking spot] taxi with [ATIS information]"
  5. TUNE & ID: and ID the required NAVAIDs for the departure if able
  6. TOGGLE & TWIST: the appropriate course and check for VOR/TACAN switch in the appropriate position for departure
  7. Contact tower for takeoff and comply with any special instructions provided by tower
    • UHF: "[place] tower, [call sign], [place] takeoff"
  8. When directed switch to departure control and make the off report
    • UHF: "[place] departure, [call sign], off [place], passing [altitude] for [altitude]"
  9. Comply with radar vector departure or DP instructions as appropriate
    • Accelerate to cruise speed once you level off before you comply with the rest of the DP, unless there is something restricting you from doing so

NOTE:
The departure phase is considered complete after joining the air route structure at the completion of the DP or when ATC instructs you to "resume own navigation"

DP Chart legend
Takeoff Minimums and Obstacle Departure Procedure
Citrus Five Departure
Figure 1: Instrument Flying Handbook, Obstacle Departure Procedures (ODP) and Standard Instrument Departures (SIDs)

Development:

  • When an instrument approach is initially developed for an airport, the need for DPs is assessed. The procedure designer conducts an obstacle analysis to support departure operations. If an aircraft may turn in any direction from a runway within the limits of the assessment area (see paragraph 5-2-8b3) and remain clear of obstacles, that runway passes what is called a diverse departure assessment and no ODP will be published. A SID may be published if needed for air traffic control purposes. However, if an obstacle penetrates what is called the 40:1 obstacle identification surface, then the procedure designer chooses whether to:
    • Establish a steeper than normal climb gradient; or
    • Establish a steeper than normal climb gradient with an alternative that increases takeoff minima to allow the pilot to visually remain clear of the obstacle(s); or
    • Design and publish a specific departure route; or
    • A combination or all of the above
  • Criteria to provide obstruction clearance:
    • Unless specified otherwise, required obstacle clearance for all departures, including diverse, is based on the pilot crossing the departure end of the runway at least 35 feet above the departure end of runway elevation, climbing to 400 feet above the departure end of runway elevation before making the initial turn, and maintaining a minimum climb gradient of 200 feet per nautical mile (FPNM), unless required to level off by a crossing restriction, until the minimum IFR altitude. A greater climb gradient may be specified in the DP to clear obstacles or to achieve an ATC crossing restriction. If an initial turn higher than 400 feet above the departure end of runway elevation is specified in the DP, the turn should be commenced at the higher altitude. If a turn is specified at a fix, the turn must be made at that fix. Fixes may have minimum and/or maximum crossing altitudes that must be adhered to prior to passing the fix. In rare instances, obstacles that exist on the extended runway centerline may make an "early turn" more desirable than proceeding straight ahead. In these cases, the published departure instructions will include the language "turn left(right) as soon as practicable." These departures will also include a ceiling and visibility minimum of at least 300 and 1. Pilots encountering one of these DPs should preplan the climb out to gain altitude and begin the turn as quickly as possible within the bounds of safe operating practices and operating limitations. This type of departure procedure is being phased out
    • Note: "Practical" or "feasible" may exist in some existing departure text instead of "practicable"
    • ODPs and SIDs assume normal aircraft performance, and that all engines are operating. Development of contingency procedures, required to cover the case of an engine failure or other emergency in flight that may occur after liftoff, is the responsibility of the operator. (More detailed information on this subject is available in Advisory Circular AC 120-91, Airport Obstacle Analysis, and in the "Departure Procedures" section of chapter 2 in the Instrument Procedures Handbook, FAA-H-8261-1)
    • The 40:1 obstacle identification surface (OIS) begins at the departure end of runway (DER) and slopes upward at 152 FPNM until reaching the minimum IFR altitude or entering the en route structure. This assessment area is limited to 25 NM from the airport in nonmountainous areas and 46 NM in designated mountainous areas. Beyond this distance, the pilot is responsible for obstacle clearance if not operating on a published route, if below (having not reached) the MEA or MOCA of a published route, or an ATC assigned altitude. See FIG 5-2-1. (Ref 14 CFR 91.177 for further information on en route altitudes)
    • Note: ODPs are normally designed to terminate within these distance limitations, however, some ODPs will contain routes that may exceed 25/46 NM; these routes will ensure obstacle protection until reaching the end of the ODP
    • Obstacles that are located within 1 NM of the DER and penetrate the 40:1 OCS are referred to as "low, close-in obstacles." The standard required obstacle clearance (ROC) of 48 feet per NM to clear these obstacles would require a climb gradient greater than 200 feet per NM for a very short distance, only until the aircraft was 200 feet above the DER. To eliminate publishing an excessive climb gradient, the obstacle AGL/MSL height and location relative to the DER is noted in the "Take-off Minimums and (OBSTACLE) Departure Procedures" section of a given Terminal Procedures Publication (TPP) booklet. The purpose of this note is to identify the obstacle(s) and alert the pilot to the height and location of the obstacle(s) so they can be avoided. This can be accomplished in a variety of ways, e.g., the pilot may be able to see the obstruction and maneuver around the obstacle(s) if necessary; early liftoff/climb performance may allow the aircraft to cross well above the obstacle(s); or if the obstacle(s) cannot be visually acquired during departure, preflight planning should take into account what turns or other maneuver may be necessary immediately after takeoff to avoid the obstruction(s)
    • Climb gradients greater than 200 FPNM are specified when required to support procedure design constraints, obstacle clearance, and/or airspace restrictions. Compliance with a climb gradient for these purposes is mandatory when the procedure is part of the ATC clearance, unless increased takeoff minimums are provided and weather conditions allow compliance with these minimums. Additionally, ATC required crossing restrictions may also require climb gradients greater than 200 FPNM. These climb gradients may be amended or canceled at ATC's discretion. Multiple ATC climb gradients are permitted. An ATC climb gradient will not be used on an ODP
    • Example: "Cross ALPHA intersection at or below 4000; maintain 6000." The pilot climbs at least 200 FPNM to 6000. If 4000 is reached before ALPHA, the pilot levels off at 4000 until passing ALPHA; then immediately resumes at least 200 FPNM climb
    • Example: "TAKEOFF MINIMUMS: RWY 27, Standard with a minimum climb of 280' per NM to 2500, ATC climb of 310' per NM to 4000 ft." A climb of at least 280 FPNM is required to 2500 and is mandatory when the departure procedure is included in the ATC clearance. ATC requires a climb gradient of 310 FPNM to 4000, however, this ATC climb gradient may be amended or canceled
    • Climb gradients may be specified only to an altitude/fix, above which the normal gradient applies
    • Example: "Minimum climb 340 FPNM to ALPHA." The pilot climbs at least 340 FPNM to ALPHA, then at least 200 FPNM to MIA
    • Some DPs established solely for obstacle avoidance require a climb in visual conditions to cross the airport or an on-airport NAVAID in a specified direction, at or above a specified altitude. These procedures are called Visual Climb Over the Airport (VCOA)
    • Example: "Climb in visual conditions so as to cross the McElory Airport southbound, at or above 6000, then climb via Keemmling radial zero three three to Keemmling VORTAC"

Locating DP Procedures:

  • DPs will be listed by airport in the IFR Takeoff Minimums and (Obstacle) Departure Procedures Section, Section L, of the Terminal Procedures Publications (TPPs). If the DP is textual, it will be described in TPP Section L. SIDs and complex ODPs will be published graphically and named. The name will be listed by airport name and runway in Section L. Graphic ODPs will also have the term “(OBSTACLE)” printed in the charted procedure title, differentiating them from SIDs
    • An ODP that has been developed solely for obstacle avoidance will be indicated with the symbol "T" on appropriate Instrument Approach Procedure (IAP) charts and DP charts for that airport. The "T" symbol will continue to refer users to TPP Section C. In the case of a graphic ODP, the TPP Section C will only contain the name of the ODP. Since there may be both a textual and a graphic DP, Section C should still be checked for additional information. The non-standard takeoff minimums and minimum climb gradients found in TPP Section C also apply to charted DPs and radar vector departures unless different minimums are specified on the charted DP. Takeoff minimums and departure procedures apply to all runways unless otherwise specified. New graphic DPs will have all the information printed on the graphic depiction. As a general rule, ATC will only assign an ODP from a non-towered airport when compliance with the ODP is necessary for aircraft to aircraft separation. Pilots may use the ODP to help ensure separation from terrain and obstacles

Responsibilities:

  • Each pilot, prior to departing an airport on an IFR flight should:
    • Consider the type of terrain and other obstacles on or in the vicinity of the departure airport;
    • Determine whether an ODP is available;
    • Determine if obstacle avoidance can be maintained visually or if the ODP should be flown; and
    • Consider the effect of degraded climb performance and the actions to take in the event of an engine loss during the departure. Pilots should notify ATC as soon as possible of reduced climb capability in that circumstance
NOTE:
Guidance concerning contingency procedures that address an engine failure on takeoff after V1 speed on a large or turbine-powered transport category airplane may be found in AC 120-91, Airport Obstacle Analysis
  • Pilots should not exceed a published speed restriction associated with a SID waypoint until passing that waypoint
  • After an aircraft is established on an SID and subsequently vectored or cleared off of the SID or SID transition, pilots must consider the SID canceled, unless the controller adds "expect to resume SID." Aircraft may not be vectored off of an ODP until at or above the MVA/MIA, at which time the ODP is canceled
  • Aircraft instructed to resume a SID that contains ATC altitude restrictions, shall be issued/reissued all applicable restrictions or shall be advised to comply with those restrictions
  • If prior to or after takeoff an altitude restriction is issued by ATC, all previously issued "ATC" altitude restrictions are cancelled including those published on a SID
  • ATC crossing altitude restrictions published on SIDs are identified on the chart with "(ATC)" following the altitude restriction. This will indicate to the pilot and the controller that this restriction is for ATC purposes and may be deleted by ATC. When an ATC crossing altitude has been established prior to the beginning of a transition route, a minimum altitude for obstruction clearance or other design constraints will also be published at the same fix adjacent/below the "(ATC)" altitude. The absence of "(ATC)" at a "minimum altitude" indicates the restriction is there to support obstacle clearance, airspace restrictions, Navaid reception, and/or other reason(s) that mandate compliance. These altitudes CANNOT be lowered or cancelled by ATC. A standalone "(ATC)" altitude restriction may also be located on a transition route; however, it must never be lower than the published Minimum Enroute Altitude (MEA)
  • Altitude restrictions published on an ODP are necessary for obstacle clearance and/or design constraints. Compliance with these restrictions is mandatory and CANNOT be lowered or cancelled by ATC

  • Obstacle clearance responsibility also rests with the pilot when he/she chooses to climb in visual conditions in lieu of flying a DP and/or depart under increased takeoff minima rather than fly the climb gradient. Standard takeoff minima are one statute mile for aircraft having two engines or less and one-half statute mile for aircraft having more than two engines. Specified ceiling and visibility minima (VCOA or increased takeoff minima) will allow visual avoidance of obstacles until the pilot enters the standard obstacle protection area. Obstacle avoidance is not guaranteed if the pilot maneuvers farther from the airport than the specified visibility minimum prior to reaching the specified altitude. DPs may also contain what are called Low Close in Obstacles. These obstacles are less than 200 feet above the departure end of runway elevation and within one NM of the runway end, and do not require increased takeoff minimums. These obstacles are identified on the SID chart or in the Take-off Minimums and (Obstacle) Departure Procedures section of the U. S. Terminal Procedure booklet. These obstacles are especially critical to aircraft that do not lift off until close to the departure end of the runway or which climb at the minimum rate. Pilots should also consider drift following lift-off to ensure sufficient clearance from these obstacles. That segment of the procedure that requires the pilot to see and avoid obstacles ends when the aircraft crosses the specified point at the required altitude. In all cases continued obstacle clearance is based on having climbed a minimum of 200 feet per nautical mile to the specified point and then continuing to climb at least 200 foot per nautical mile during the departure until reaching the minimum enroute altitude, unless specified otherwise
  • ATC may assume responsibility for obstacle clearance by vectoring the aircraft prior to reaching the minimum vectoring altitude by using a Diverse Vector Area (DVA). The DVA has been assessed for departures which do not follow a specific ground track. ATC may also vector an aircraft off a previously assigned DP. In all cases, the 200 FPNM climb gradient is assumed and obstacle clearance is not provided by ATC until the controller begins to provide navigational guidance in the form of radar vectors
  • Note: When used by the controller during departure, the term "radar contact" should not be interpreted as relieving pilots of their responsibility to maintain appropriate terrain and obstruction clearance which may include flying the obstacle DP
  • Pilots must preplan to determine if the aircraft can meet the climb gradient (expressed in feet per nautical mile) required by the departure procedure, and be aware that flying at a higher than anticipated ground speed increases the climb rate requirement in feet per minute. Higher than standard climb gradients are specified by a note on the departure procedure chart for graphic DPs, or in the Take-Off Minimums and (Obstacle) Departure Procedures section of the U.S. Terminal Procedures booklet for textual ODPs. The required climb gradient, or higher, must be maintained to the specified altitude or fix, then the standard climb gradient of 200 ft/NM can be resumed. A table for the conversion of climb gradient (feet per nautical mile) to climb rate (feet per minute), at a given ground speed, is included on the inside of the back cover of the U.S. Terminal Procedures booklets

RNAV Departure Procedures:

  • All DPs, either textual or graphic may be designed using either conventional or RNAV criteria
    • RNAV procedures will have RNAV printed in the title
      • Example: SHEAD TWO DEPARTURE (RNAV)
    • ODPs provide obstruction clearance via the least onerous route from the terminal area to the appropriate en route structure
    • ODPs are recommended for obstruction clearance and may be flown without ATC clearance unless an alternate departure procedure (SID or radar vector) has been specifically assigned by ATC
    • Graphic ODPs will have (OBSTACLE) printed in the procedure title
      • Example: GEYSR THREE DEPARTURE (OBSTACLE)
      • Example: CROWN ONE DEPARTURE (RNAV) (OBSTACLE)
  • All public RNAV SIDs and graphic ODPs are RNAV 1
    • These procedures generally start with an initial RNAV or heading leg near the departure runway end
    • In addition, these procedures require system performance currently met by GPS or DME/DME/IRU RNAV systems that satisfy the criteria discussed in AC 90-100A, U.S. Terminal and En Route Area Navigation (RNAV) Operations
    • RNAV 1 procedures require the aircraft's total system error remain bounded by 1 NM for 95% of the total flight time

Reference:



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