Departure Procedures (DPs)
In this TOPIC, we’ll cover Instrument Departure Procedures, and how not to be that guy in the picture above!
The Procedures we will talk about are:
- Standard Instrument Departures (SIDs)
- Obstacle Departure Procedures (ODPs)
- Diverse Vector Areas (DVAs)
- Visual Climb Over Airport (VCOA)
As you can see, we love acronyms in instrument flying just as much as in VFR flying!
Before we can talk about the Departure Procedures, there’s one more acronym we need to cover, TERPS Specialists (Terminal Instrument Procedures Specialists)
These are the guys that design, build, and test fly instrument procedures of all types. For our purposes, I’ll make it simple. What we care about is the specific criteria that make them post a DP or not.
When no obstacle penetrates the 40:1 slope (152′ per nm slope), then no DP will be published for that Airport. The TERPS guys look out either 25nm from the airport (non-mountainous terrain), or 46nm (mountainous terrain) from the airport to determine this (using that 40:1 or 152′ per nm slope).
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’s 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 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 filled 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.
Obstacle Departure Procedures (ODPs)
ODPs come in two forms, textual and graphic. When the textual ODP is considered to be “complex” (lots of turns or weird instructions), the FAA will also make it available in graphical form. It’s important to remember that although there is no regulation forcing you to fly a published ODP, it is very wise to do so as those are flight tested routes proven to be safe. Flying off on some random vector assigned by ATC is not a 100% guarantee of safety.
Where do you find them?
ODPs can be found in the “TAKEOFF MINIMUMS” section of the chart supplement.
Here, nestled in with the takeoff minimums (that do not apply to part 91 operations, but are a really good idea to follow, or even follow more strict minimums for departing IFR) and TAKEOFF OBSTACLE NOTES, you’ll find the applicable DEPARTURE PROCEDURES. Now not all runways at an airport may have such a procedure. If there is not an obstacle that penetrates the protective climb gradient, the FAA will not publish a procedure for that runway (remember that they are assuming you have at least a 200′ per nm climb ability. If your airplane can’t do that, all bets of protection are off).
For KVNC, departing runway 31 the ODP instructs you to climb on heading 305 degrees up to 1,500′ msl before making any turns. Looking upwind of runway 31 in Venice, we can see the idea behind this (the towers east of the extended centerline of runway 31).
Do ODPs really matter since they’re not regulatory? Well ATC is NOT responsible for your separation with terrain or other aircraft for that matter in Class G airspace, and not every clearance they give you will protect you even if you do have the 200′ per nm climb ability. The only way to be sure not to hit something is to fly a published procedure.
A pilot in a Cessna 210 with over 700 hours in that airplane departs IFR out of KMVL from RWY 19, with a clearance from ATC of Direct CAM VOR. He and his two passengers die shortly after takeoff when he impacts rising terrain south of the airport. He did not fly the ODP for RWY 19 out of KMVL, nor did he note it in his remarks section of the flight plan, showing any intent to comply with it. Click Here to Read the NTSB Report
Remember: You are fully responsible for the safety of your passengers, yourself, people on the ground, and your airplane. Make the safe choice, spend an extra 2 minutes flying around the terrain to get to a higher altitude before proceeding on course, whether it’s IFR, MVFR, or even just nighttime or an unfamiliar airport. Better to waste 3 minutes flying than the last 30 years of your life.
How to File an ODP
Filing a SID is easy, filing an ODP isn’t really an option in the ROUTE section, but you can put it in the remarks section, and inform ATC when picking up your clearance that you intend to fly the ODP, then on the route they clear you on. Make sure the ODP doesn’t disagree with the route they assign you. If there are any conflicts (i.e. your clearance includes instructions “CESSNA 8MA, ENTER CONTROLLED AIRSPACE HEADING 090”), then looking at departing RWY 31 from KVNC that would not work (you can’t fly heading 305 to comply with the ODP, because ATC wants you on a heading of 090 when you reach 700′ agl). In this case where the ODP disagrees with an ATC clearance, query the controller and consider using a different runway, getting approval to fly the ODP, or modifying the clearance (do this BEFORE you takeoff!).
So ya know how I said above that ODPs come in two forms, graphic and textual? Well good luck finding a Graphic ODP anywhere, even when the textual procedure is very complex. In fact, the lack of graphic ODPs is so great that NBAA actually wrote a formal complaint letter to the FAA about it back in September of 2006. Not much has been done on this front since that letter, other than more RNAV SIDs have been introduced into the IFR System. The trouble with RNAV SIDs is you need a legal GPS to fly them, so if you have only VORs (equipment “/U”), then you’re left out of all the fun. A good reason to get your airplane equipped with a certified GPS is the vast availability of RNAV SIDs popping up. They are both efficient, all come with a graphic representation, and guarantee you obstacle clearance!
When a graphic ODP does exist, you will see a note in the DEPARTURE PROCEDURE section that reads like this:
Click here to see an example of a Graphic ODP
Take a look here to the left at the textual ODP for KPUC in Utah. It’s fairly complex, yet there is no graphical depiction of it anywhere! Read and hope you understand what you are supposed to do.
Here’s an example of an RNAV SID, it’s a bit easier to follow reading both the text and seeing it visually depicted where you will depart the runway from.
Diverse Vector Area (DVA)
What in the heck is that!? Well let’s translate from FAA to English: It’s an area that’s been pre-cleared by an FAA survey crew to ensure you will have obstacle protection if you accept a radar vector on departure from ATC.
This means that as long as you comply with the restrictions in the DIVERSE VECTOR AREA section of the TAKEOFF MINIMUMS booklet, you will be guaranteed obstacle protection. As an example, let’s take a look at departing from runway 16 in Belingham, Washington.
When taking off from KBLI on runway 16, you have a couple options for avoiding terrain. One is the textual ODP, the other would simply be to take a vector to your assigned route from ATC. You can safely do this if you have the ability to maintain a minimum climb gradient of 360′ per nm up to 2,700′ msl (doubt you’ll be able to comply with that in a heavily loaded 172, or a piston twin after one engine fails).
The idea here is that after reaching 2,700′, the standard 200′ per nm climb will give you enough protection for whatever direction ATC sends you, but you need to get up to 2,700′ a little steeper than usual.
This can be a great tool to “double check” ATC and make sure that they are keeping you safe. Since Minimum Vectoring Altitudes are not published for pilots to read, and we never really know if a controller is having a “human” moment and making an error vectoring us into terrain, using a published procedure like a SID, ODP, or DVA will help you stay alive longer so you can continue donating your money to AVFUEL and ROUTE 66!
Visual Climb Over Airport (VCOA)
A Visual Climb Over Airport (VCOA) procedure is a departure option for an IFR aircraft, operating in visual meteorological conditions equal to or greater than the specified visibility and ceiling, to visually conduct climbing turns over the airport to the published “climb−to” altitude from which to proceed with the instrument portion of the departure. VCOA procedures are developed to avoid obstacles greater than 3 statute miles from the departure end of the runway as an alternative to complying with climb gradients greater than 200 feet per nautical mile.
Pilots are responsible to advise ATC as early as possible of the intent to fly the VCOA option prior to departure
Here are two examples of a VCOA procedure:
A couple things about VCOAs
- Obstacle clearance is only good for the visibility specified on the procedure, meaning if the required visibility is 3300-2, then you are only guaranteed obstacle protection for within 2 miles of the airport.
- You must advise ATC you plan to use the VCOA option before departing
- You still need the minimum 200′ per nm climb rate to get from the end of the VCOA to the en-route portion of your flight plan.
- VCOAs can be part of a Graphic or Textual ODP (the two options are shown above for two separate airports)
- To see an VCOA Procedure discussed in depth, click here
Example ATC Clearance:
“Climb in visual conditions so as to cross the McElory Airport southbound, at or above 6000, then climb via Keemmling radial (033) zero three three to Keemmling VORTAC.”
So what’s your favorite way to climb out IFR?
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