Feeling confused about "Descend Via" clearances? Here are answers to your most common questions directly from the FAA...

1) What does a "DESCEND VIA" clearance mean?

Comply with the lateral path of the STAR. Comply with all published speed restrictions. Comply with all published altitude restrictions.

2) I am cleared to "DESCEND VIA" a STAR. What altitude am I cleared to?

The charted "Bottom Altitude" of the procedure, unless ATC assigns a different altitude.

3) How do I determine the "Bottom Altitude" of the STAR?

It is the last published altitude on the STAR or STAR Runway Transition that you are assigned.

4) If an instrument approach procedure connects to the STAR, are the instrument approach procedure altitudes part of the STAR?

NO. You must receive an appropriate approach clearance from ATC before descending below the bottom altitude of the STAR on a "Descend Via" clearance.

5) When a controller issues a "Descend Via" clearance, am I required to read it back?

YES. Reading back the descend via clearance, along with the name and number of the procedure (BWILL TWO), assures the controller you will comply with all restrictions and you are navigating on the correct procedure and version. This includes the runway transition, if assigned.

6) Are MEAs/MOCAs considered altitude restrictions for "Descend Via" purposes?

NO. MEAs and MOCAs are not considered altitude restrictions for the purposes of a "Descend Via" clearance. Only "At," "At or Above," and "At or Below" and "Window" restrictions published at a waypoint/fix are considered altitude restrictions for the purposes of a "Descend Via" clearance. A pilot should not descend to a segment MEA or MOCA when cleared to "Descend Via."

7) Should I begin an immediate descent when issued a "Descend Via" clearance?

You are permitted to descend at your discretion in order to meet the published restrictions. However, a premature descent could impact spacing with other arrivals and can reduce the potential fuel savings of flying the appropriate profile.

8) Can ATC issue a "Descend Via" clearance for a STAR that does not have published crossing restrictions? Some STARs do not have crossing restrictions but only MEAs and or MOCAs.

A "Descend Via" clearance will not be used on a STAR that does not have published altitude restrictions.

9) I am cleared to "descend via" a STAR, but the controller adds "EXCEPT MAINTAIN (Altitude)." What altitude am I cleared to and do I have to comply with published altitude restrictions during my descent?

You must comply with all published altitude and speed constraints until reaching the assigned altitude, unless explicitly cancelled by ATC.

10) I'm on a descend via clearance and the controller vectors me off the procedure. Do I continue to "descend via?"

NO. You are laterally and vertically off of the procedure. The controller will issue an altitude to maintain and provide a further "expect" clearance. Note: Request an altitude to maintain if the controller does not provide one.

11) What if there are "EXPECT" altitudes published on the STAR?

Expect altitudes are for planning purposes only, and you are not expected to comply with published "EXPECT" restrictions unless ATC has specifically instructed you to do so. ATC will not use "Descend Via" on STARs that contain only "EXPECT" restrictions.

However, if the STAR contains a mix of "EXPECT" restrictions and published mandatory restrictions, ATC may use "Descend Via" if the aircraft has passed the "EXPECT" restrictions or if they specifically assign a restriction for the "EXPECT" waypoint/fix with the "Descend Via" Clearance.

12) What if I am given a clearance to "Descend and Maintain" an altitude?

Unlike a "Descend Via" clearance, when cleared to "Descend and Maintain," you are expected to vacate your current altitude and commence an unrestricted descent to comply with the clearance.

For aircraft already descending via a STAR, published altitude restrictions are deleted unless reissued by ATC. Speed restrictions remain in effect unless the controller explicitly cancels or amends the speed restrictions.

13) What if I receive a "Cleared" or "Cleared Via" clearance; am I permitted to descend to meet any published altitudes?

NO. Only a "Descend Via" clearance gives you the vertical authorization. The other two examples are a "lateral" clearance. Note: Compliance with published speed restrictions are required, unless canceled or modified by ATC.

14) I just received a descend via clearance from En Route ATC (ARTCC) which included "Runway 26 transition." Is that also my landing runway?

NO. ARTCC's cannot assign a landing runway. However, many issue the "runway transition" with the "Descend Via" clearance. The approach (TRACON) controller will assign the actual or expected landing runway.

15) Will the assignment of a runway transition always include a runway number?

NO. You may receive a directional clearance such as "Landing North." Generally, chart notes would indicate the runway or runways that are associated with the "landing direction" runway transition. Again, the TRACON controller will assign the actual runway.

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