Standard Instrument Departure Procedure (SID)
SIDs can help condense your flight plan in a nice neat package, reduce ATC workload, and make receiving your clearance from ATC much easier. However, if you ever decide you don’t want to use a SID, and don’t want ATC to file you using one, just place “NO SIDS” in the remarks section of your flight plan when you file it.
Here are a few things to remember before we jump into SIDs:
- You can always request a different route from ATC
- SIDs guarantee you obstacle clearance when you follow all of their stipulations
- Can be filed as the sole part of your route
- They are often two pages, so don’t miss the second one!
Parts of the SID
What we’re concerned with here is:
- Top Altitude (how high can we climb to before ATC needs to give us permission to climb higher)
- Departure Frequency
- Textual Instructions Departing a Particular Runway (Departure Route Description)
- Departure Obstacle Notes
- Requirement Notes (i.e. Radar, DME, etc.)
- Speed Restrictions
- What applies to who (what notes apply to what types of aircraft, Propeller, Turboprop, Turbojet)
- Verify this departure is for the AIRPORT you are departing from (the same departure procedure will apply to multiple airports, but variations will exist depending on what airport you are departing from. Be sure you are looking at the right airport so you have the proper notes)
When cleared to Climb Via in your departure clearance, this is how high you can go until the departure controller assigns you a higher altitude. If you are assigned either a higher or lower altitude on departure other than the TOP ALTITUDE, fly what you are assigned instead.
When assigned a SID, don’t be surprised when clearance doesn’t tell you a departure frequency, they just want to save time and talking and have you get it from the SID instead. (For most GA pilots, ATC will often include the departure frequency anyways just to be helpful, unless they are busy with other duties.)
Departure Route Description
This is the gold mine of the SID. It spells out in plain English exactly what they want you to do. I.E. Departing either runway 6 or 24 out of KARB, climb on the assigned heading from ATC, expect radar vectors to join the 106-degree radial from DXO, then fly on that radial to SPHERE, then on the ACO radial 329 to the ACO VOR. Maintain 3,000′ unless told otherwise by ATC, and expect ATC to give you your filed altitude 10 minutes after departure. This all comes in real handy when you have a radio failure shortly after takeoff in IMC, simply follow your Assigned route, and fly at 3,000′ until 10 minutes after departure, then climb to your filed altitude, or the minimum altitude for the route you are flying (whichever is higher).
Departure Obstacle Notes
Ya, I know, most people don’t read these ever. But if you could talk to the handful of guys who flew their perfectly good airplanes into the aforementioned obstacles most people ignore (unfortunately no one can talk to those guys now), they may tell you to take a minute or two and review them! It’s fairly straightforward, look at the runway you are departing, visualize where the obstacles are based on those notes.
So it’s really embarrassing when you file a SID flying your Cessna or Piper, and that SID was restricted to TURBOJETS ONLY. Sorry, you’re not part of the big fast jet club just yet, give it time, you’ll get there one day! Be sure to read any and all notes you can find tucked away and hidden in the corners of SIDs or STARs to ensure you are legal, and also to save yourself some embarrassment.
Yet another thing you will have to scour the plate for, be sure to look in every corner and crevice to find speed restrictions that will apply to you. Some you may not be able to comply with and will have to advise ATC prior to departure (your Cessna 172 probably won’t be able to climb at 280 knots above 10,000′, most likely, if you attempt it somehow, it will just plummet to the ground at 300+ knots).
Who the Departure is For
Self-explanatory, some SIDs are for Turbojets only or Turboprops only.
Verify the Airport on the SID Plate
The ACRON FIve Departure in the example above covers multiple airports. The instructions may differ slightly on how to fly the SID depending on what airport you are departing from. Be sure to verify the correct name of your departure airport in the top corner of the chart.
How Do You File a SID?
If you want to fly KARB to KCAK, you could simply file your route as “ACO5.ACO” This shows ATC you are filing the Acron Five departure, Acron Transition. Your Departure and Destination airport are taken care of in the flight plan (already listed as the departure point and end point), thus your route is simply ACO5.ACO You can then begin an approach right from the ACO VOR, and you have a clear route to fly in the event of a communications failure.