A descend via clearance is usually straightforward, but there are a few 'gotchas' you should be aware of...

Find The Lowest Crossing Altitude, And Don't Descend Below It

The question is: "What's the lowest altitude you can descend to when given a 'descend via' clearance?" You're given the following STAR chart to review (pictured below).

On the BEREE 1 Arrival into KDFW, the lowest published crossing restriction is a mandatory 11,000' crossing at DIETZ. The lowest crossing restriction is the lowest you can descend with a 'descend via' clearance, so in this example, you can't go lower than 11,000' without further instruction from ATC.

Notice there are two fixes after this, WHOOT and HEDMN. Between them, the Minimum En Route Altitude (MEA) is 4,000 feet and the Minimum Obstruction Clearance Altitude (MOCA) is 2,100 feet.

You cannot descend to these altitudes on a descend via clearance. If you haven't flown a lot of STARs yet (most instrument-rated pilots haven't), this is a common question that might trip you up. You must stop your descent at 11,000 feet at DIETZ and wait for a lower assigned altitude by ATC. An exception to this would be ATC clearing you to "descend via the XXXX Arrival, EXCEPT maintain XXXXX feet."

Understanding Runway Transitions

Here's where things get a little tricky. If you're flying the BEREE 1, it's hard to mess up your minimum altitude if you understand the difference between an MEA and a crossing restriction. But what happens when a STAR connects directly with a runway's instrument approach?

Take a look at Cleveland's BRWNZ 4 Arrival below. The last crossing restriction on the STAR for KCLE landing runways 24L/R is at LLROY: 5,000 feet and 210 knots.

Approach control might let you know to expect Runway 24L/R, but unless ATC clears you for the ILS to Runway 24L/R, you cannot descend below 5,000 feet. An "expect" runway assignment does not give you permission to descend either.

Has This Happened To You?

If you're ever in doubt about a clearance, ask ATC for clarification. Until you're cleared to a lower altitude, or cleared on an instrument approach, you cannot leave the last crossing restriction of a STAR following a descend via clearance.

What airports have arrivals that make this confusing? Have you ever flown a STAR straight into an instrument approach? Tell us in the comments below.