Every phase of an instrument flight has a published route one can follow. They’re called Standard Instrument Departures.

To accommodate the number of airplanes in the sky, air traffic controllers need to have an organized system of routes that both they and the pilots know. The pilots carry charts and approach plates, and the controllers know those procedures by heart (but they also have copies for reference). 

For the departure phase, there is the SID, or the Standard Instrument Departure. 

Once enroute, preferred routes and airways take you to your destination. 

To get you from the airway to your destination airport, STARs (Standard Terminal Arrival Procedures) are the chart you need. 

And finally, IAPs (Instrument Approach Procedures) get you down to the runway in poor visibility. 

Let’s look more closely at the SID and why it’s so important for IFR departures. That is, after all, the best place to start.

What Is a Standard Instrument Departure (SID)?

A SID, or Standard Instrument Departure, is a standardized route for navigating aircraft from their departure runways onto nearby airways. It transitions the pilot from the terminal airport area to the enroute environment. 

The primary goal of a SID is to reduce the controller’s workload and to increase system efficiency. 

The idea is this: It’s easier for the departure controller to say, “Cleared for the ABC Departure,” than directing the pilot every step along the way. While not specifically designed for it, SIDs will guarantee the pilot of obstacle clearance as long as they are followed.

To accept a standard instrument departure, the pilot must have the most current copy of that SID in at least its text format.

SIDs are published in the TPP (Terminal Procedures Publication), also known as the approach plates, and are always in a graphic (chart) format. Of course, they’re also available from digital chart providers like ForeFlight and Jeppesen. 

Why Are Standard Instrument Departures Important?

Depending on the airports you operate out of, you can expect to get a SID on almost every flight. 

While it’s technically possible to not accept the SID, the controllers are used to using them and may continue to try to issue them. Chances are, flying SIDs will be a part of every IFR cross-country, even if you don’t use them at your home airport.

SIDs are not difficult to fly. They’re often as simple as “Fly radar vectors until V123, climb and maintain 5,000.” 

Sometimes, they have altitude restrictions and multiple steps along the way, depending on the complexity of the airspace and terrain.

For controllers, SIDs are just business as usual. Their traffic flows have been created based on the traffic arriving and departing from the surrounding airports, plus the heavily trafficked routes that transition the area.  

The busier the airport, the higher the likelihood that a standard procedure has been published and made into an official SID. 

In less busy areas, you may have noticed that the controllers issue similar clearances every time, even if there isn’t a SID. The controllers still use standardized routing, even if you don’t realize it. 

The controllers have a plan to keep the traffic flowing in an organized manner, no matter which runways are being used at the time. Even if you’re flying VFR and using flight following, you’ll often be vectored to follow some existing SIDs or departure routes.

Types of SIDs

SIDs come in three types: 

• Pilot navigation
• Radar vectors
• Combination of the two

Pilot Navigation SIDs mean that the pilot is responsible for their navigation during the SID. 

For example, the SID might say, “Fly runway heading to 3,000, then DIRECT XYZ VOR.” 

An RNAV SID allows the pilot to navigate directly to any fix. 

A Radar Vector SID means you must be in radar contact and receive vectors to fly it. Most Radar Vector SIDs read, “Fly runway heading to 3,000, then radar vectors to V-123 airway.”

It’s possible to have a hybrid SID with both pilot navigation and radar vectors. Radar vectors are often used to navigate the pilot up to a safe altitude and away from the terminal area, and then pilot navigation can be used to join the airways.

Other DPs (Departure Procedures)

Other products are available to IFR pilots departing airports. 

Standard Instrument Departures are the only ones that ATC will specifically tell you about, but you need to know about the others as well. 

ODPs are Obstacle Departure Procedures

These are text or graphic descriptions of how to depart a runway to avoid hitting anything. 

Remember, the weather might be low, and there are no legal minimums for takeoff under Part 91. ODPs are not published for every runway at every airport, but they are published if there’s stuff you could hit. 

ODPs or alternative takeoff minimums are used when obstacles penetrate a plane that extends from the runway end and climbs at 152 fpnm (feet per nautical mile). 

The AIM (Aeronautical Information Manual) tells pilots that it’s their responsibility to determine how to depart the runway environment safely. In many cases, it can simply be done visually. If that cannot be done, it’s up to the pilot to determine if they need to follow a published ODP.

ODPs are published in the Takeoff Minimums and Departure Procedures section of the TPP (Terminal Procedures Publication). ODPs may be followed without ATC guidance unless the pilot has accepted a SID or radar vectors.

What is the Difference between an ODP and a SID?

Both ODPs (Obstacle Departure Procedures) and SIDs (Standard Instrument Departures) are types of Departure Procedures. 

ODPs are used by the pilot to ensure clearance above obstacles when leaving an airport. They may be text or graphic in format. 

SIDs are air traffic control procedures issued to pilots that provide route guidance, transitioning them from the airport to the enroute environment. 

Standard Instrument Departure Examples

The first step to successfully flying a Standard Instrument Departure is to have reviewed it before flight. Even if you aren’t planning on filing it into your flight plan, if a SID is available for your departure airport, you should be ready to accept it. 

Always look for SIDs as part of your pre-flight planning and review the preferred routes. You’re more than likely to be issued them anyway.

Don’t forget to check your airport and runway for non-standard takeoff minimums and ODPs. Pilots must maintain a standard climb gradient for IFR flights: takeoff and cross the departure end of the runway at least 35 feet AGL, then climb at least 200 fpnm (feet per nautical mile). 

No turns should be made prior to 400 feet AGL. If a higher climb gradient is necessary for crossing restrictions, it will be noted on the ODP or SID. As part of your pre-flight planning, ensure that you will be able to meet these standards.

Flying any of these procedures is as simple as following the directions given.

Most have a chart view and a text description that follows the route step-by-step. Where applicable, the chart view includes the minimum sector altitudes and takeoff minimums. 

Departing from Addison, there are six possible standard SIDs and three RNAV SIDs. The Dallas Three Departure takes traffic from Addison Airport and vectors it to the Maverick VOR (TTT), then via one of four transitions to Belcher, Little Rock, Soldo, or Texarkana.

For example, on a flight bound for Little Rock, the flight may be cleared via the Dallas Three Departure, Little Rock transition.

From the charts, we can see that that means radar vectors to the appropriate route and maintain altitudes assigned by ATC. From over the TTT VOR, the route takes the 064 radial to ORTRO, then joins the LIT 253 radial to the LIT VOR.

So, in simpler terms, the flight should expect radar vectors and altitudes to join TTT R-064 outbound. 

You can view the Addison Dallas Three Departure plates here. 

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Further Reading

AIM, Chapter 5: Air Traffic Procedures, Section 2 

Instrument Flying Handbook 

Instrument Procedures Handbook, Chapter 1: Departure Procedures