On Instruments: Coming and going

The kicker cropped up during a preflight session for a dual cross-country IFR flight. “Just put ‘no SIDs or STARs’ in the remarks section of the flight plan,” one of my instructors said. I didn’t know what to think. Was this an insider shortcut to avoid the hassle of flying these procedures? Or was it laziness—a way to skip teaching, and learning to fly, SIDs and STARs?

Well, that was then, when flying a challenging SID or STAR could mean a lot of quick-handed VOR-tuning—and having two VOR heads was the upscale way to create cross-radial fixes. Now, praise be, we have GPS for extremely accurate fix-to-fix navigation, and many of us are blessed with large multifunction displays that give us exquisite situational awareness. Throw in an auto-pilot and the airplane can fly the procedures by itself. But I still sense that many pilots may have subpar understandings of arrival and departure procedures. In the interest of a quick refresher, here’s a lightning-round review of SIDs and STARs.

Pilots flying to less-busy airports may not be issued a STAR, but practically all large or towered airports have published STARs, or RNAV STARs, and transitions for those airplanes equipped with flight management systems and GPS. If you’re flying a turbine-powered airplane you’re practically guaranteed to get a STAR clearance; less so for piston singles flying at lower altitudes. A single airport could have multiple STARs, and a single STAR may serve multiple runways or airports, so be sure to brief the STAR long before you approach the terminal area. They’re graphical illustrations of inbound flight paths, and have textual advice accompanying these charts. With GPS, loading the STAR is a breeze. Without it, staying ahead of a complicated STAR can be a two-person job.

The “climb via” and “descend via” clearances for SIDs and STARs are relatively new and may catch the unwary by surprise. If ATC gives you a “descend via” clearance, as in “descend via the DSERT Two arrival,” then you’re cleared to navigate both laterally and vertically, according to the STAR; ATC shouldn’t give you step-down altitudes on your way in. Just fly the procedure, descending on your own to the next altitude or fix along your route—making sure that you meet any crossing restrictions at each fix.

With plain-Jane STARs having no “descend via” wording, ATC keeps you separated from traffic as well as gives you altitudes to descend to, or maintain, so this means you follow each clearance as it comes. Many STARs—whether with descend-via clearances or not—end with vectors to a final approach course.

Departure procedures (DPs) that are SIDs are also charted, together with text descriptions. The drill here is to follow any “climb via” clearance by following the charted information, and/or adhere to ATC clearances during the procedure if not on a “climb via.”

Obstacle departure procedures (ODPs) are another type of SID. The FAA creates an ODP if high terrain or obstacles near an airport require a climb of 200 feet per nautical mile—or more—to provide safe clearance during IFR departures. It’s rare that ODPs are published in charted form. Instead, you have to look up their text descriptions in the Takeoff Minimums and (Obstacle) Departure Procedures of Section L of Terminal Procedures Publications. This section is in the front of the Standard Instrument Approach Procedures booklets as well as on the reverse side of Jeppesen approach charts. They also can be found by searching apps such as ForeFlight for airports, then selecting the dropdown menu for procedures.

Pilots should study the environment around the airport, because an ODP can be flown without an ATC clearance—unless an alternate DP or radar vectors are assigned by ATC. Technically, this means you don’t have to tell ATC that you’ll be performing an ODP—although good practice dictates that you keep them in the loop by mentioning it in the remarks section of your flight plan. It’s a good idea to fly an ODP at night, and whenever visibility is hampered by low clouds or precipitation.

Radar departures are another type of DP. Here, ATC simply issues you headings and altitudes after takeoff, until you’re told to resume your own navigation after joining the en route portion of your planned route. Diverse vector areas (DVAs), which provide safe vectoring below the local minimum vectoring altitude (MVA), may come into play when departing on radar vectors from certain airports. In a DVA, controllers will issue you initial climbs to specific altitudes that provide separation from obstructions.

In cases where your departure airport isn’t served by a tower, you can request a DP by using a clearance delivery remote communications outlet (RCO) frequency—if one is available. A telephone call to flight service also works. You’ll be given your clearance and a void time when it expires. Be in the air before the void time, or your clearance expires.

Now let’s say you’re at an airport that has instrument approaches but no tower, doesn’t have radar coverage, and has no published DPs of any type. Wherever there’s an approach, a survey of the surrounding terrain and obstacles was performed, so the absence of a DP is interpreted that none is necessary. After receiving your clearance, you can take off, maintain runway heading, and climb at a rate of 200 feet per nautical mile or better, then turn to your first en route fix and contact ATC.

Of course, a VFR departure is another tactic. This puts the burden of traffic, terrain, and cloud separation on the pilot—until ATC contact is established. Only then can the flight be continued under IFR. Yet another type of VFR departure is the visual climb over the airport (VCOA). In this situation the weather is VFR but the pilot files for a VCOA departure well before takeoff, then circles over the airport while climbing. Text instructions for the VCOA are published in the Terminal Procedures Publications, Standard Instrument Approach Procedures, and other sections of the sources mentioned above. The instructions give a “climb to” top altitude, at which point the flight can continue under IFR. In cases where an airplane can’t meet minimum IFR departure climb gradients, VCOA is a useful way of climbing higher than nearby obstacles before continuing the flight.

Are you asking for “no SIDs or STARs”? Think about what you’ve been missing. Maybe it’s time to include them in your preflight planning sessions.

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