Learn how to choose the correct SID and STAR by runway, route fix, transition, aircraft capability and ATC clearance, with common errors explained.
Choose a SID that starts from the expected departure runway and ends at, or transitions towards, your first en-route fix. Choose a STAR that begins near your last en-route fix and supports the expected arrival runway. In any flight simulator, confirm chart restrictions, aircraft capability, matching navdata and ATC clearance before flying either.
What must match when selecting a SID or STAR?
A suitable procedure must agree with the runway, en-route path, aircraft capability and published restrictions. The shortest procedure is not necessarily the correct one.
| Check | SID selection | STAR selection |
|---|---|---|
| Runway | Starts from the assigned or expected departure runway | Supports the expected arrival runway or feeds a compatible approach |
| Route connection | Ends at or transitions towards the first en-route fix | Begins at or transitions from the last en-route fix |
| Aircraft capability | Aircraft can meet navigation and climb requirements | Aircraft can meet navigation, altitude and speed requirements |
| Clearance | Matches the departure clearance | Matches the arrival assigned by ATC |
Some procedures have separate runway branches and named en-route transitions; others use one common path for several runways. A STAR may also finish at a point where radar vectors to the approach are expected, so it will not always connect directly to the runway.
How do I choose the correct SID and STAR?
- Identify the en-route endpoints. Find the first waypoint after the departure area and the last waypoint before the destination area. Do not count fixes that your planning tool inserted as part of a procedure.
- Determine the likely runways. Use an ATIS or ATC assignment when available. Without ATC, consider wind, airport flow, terrain and aircraft runway requirements rather than choosing by wind alone. Treat the destination runway as provisional because it can change during the flight.
- Filter SIDs by departure runway. From those remaining, choose the procedure or transition that joins the first en-route fix without backtracking, crossing the airport unnecessarily or creating an implausible turn.
- Filter STARs by route entry. Start with the STAR whose entry point or transition matches the direction from which the flight arrives. Then confirm that its runway branch, termination point and available approaches suit the expected landing runway. Our more detailed STAR-selection method covers arrivals with several plausible choices.
- Check every restriction. Read the chart for RNAV or other equipment requirements, minimum climb gradients, altitude windows, speed limits and notes restricting a procedure to particular runways or operations. If these symbols are unfamiliar, use our explanation of procedure charts and restrictions.
- Load and inspect the procedures. Select the runway, procedure and transition from the avionics procedure database instead of manually typing every procedure fix. Review the LEGS page and map for discontinuities, duplicate fixes, sharp reversals and missing restrictions; our procedure-loading walkthrough for simulator FMCs explains this check.
- Apply the clearance last. A flight plan is a request, not permission to fly a particular procedure. Replace the planned SID, STAR or transition if ATC assigns something different.
What if several procedures connect to the same route?
Use the procedure assigned by ATC; without ATC, prefer the one that fits the expected runway, joins the route cleanly and remains within the aircraft’s capabilities. Compare candidates in this order:
- Assigned or expected runway
- Correct route transition or terminal entry point
- Aircraft navigation and performance capability
- Published altitude, speed and operational restrictions
- Reasonable track length and direction
Do not select a SID or STAR from its name alone. Procedure names and revision numbers can change, and a familiar name may contain different runway branches or transitions in another navdata cycle.
Can ATC change the planned SID or STAR?
ATC can replace, amend or cancel a planned procedure because runway use and traffic flow may change. The clearance takes precedence over the filed flight plan, provided the aircraft can comply.
When reassigned, enter the new runway, procedure and transition, then inspect the modified route before executing it. If the aircraft cannot meet a climb gradient, navigation requirement or restriction, advise ATC rather than accepting the procedure. Our guide to handling SIDs and STARs with simulator ATC explains clearances, amendments and vectors in more depth.
Why does the FMC show a discontinuity or an odd turn?
An unexpected gap or turn usually means the wrong transition was selected, the procedure does not actually join the en-route route, or the planner and aircraft use different navdata. A runway change can also leave old approach or arrival legs in the flight plan.
- Route doubles back: choose the transition matching the adjacent en-route waypoint, then remove any duplicate waypoint.
- Procedure is missing: check whether the planner and aircraft navigation databases contain the same procedure revision. Do not manually imitate a procedure that the avionics cannot support without checking every leg and restriction.
- Discontinuity follows a vectors leg: it may be intentional. Do not close it automatically; wait for vectors or a direct-to clearance.
- STAR and approach overlap: reselect the arrival and approach, then inspect where the STAR terminates and the approach transition begins.
When should I omit a SID or STAR?
Leave the procedure out when none is published, ATC assigns vectors or a direct route, or the aircraft cannot legally or technically comply. A procedure should not be forced into a flight plan merely because the airport has one.
For an offline flight without ATC, we recommend choosing a plausible procedure from the available charts and treating the arrival runway as changeable. For online controlled flying, file the expected procedures but be ready to reprogramme the route after receiving the actual clearance.