"Climb/Descend Via" FAA vs. ICAO Explained (Revised SEP2017)

RNAV SID/STARS have made it possible for ATC to reduce their required communication to operating aircraft. Reduced chatter on the radio is helpful BUT this raises the level of ATC clearance understanding and compliance inside our cockpits. ICAO has issued Amendment #7 to Document #4444, PANS-Air Traffic Management. This is effective 10NOV16, just a few days from now. Several significant changes are in this document. The “Descend/Climb Via…” part seems to be getting the most questions and concern. This is particularly so when USA pilots are comparing ICAO based air traffic control procedures to domestic USA procedures.

First the Familiar, FAA defined “Descend/Climb Via…”

The pilot reference for this procedure in the Aeronautical Information Manual, Paragraphs 5-2-8 and 5-4-1. Here’s the operable sentence from Paragraph 5-4-1: “…This authorization may contain the phraseology “DESCEND VIA.” If vectored or cleared to deviate off of a STAR, pilots must consider the STAR canceled, unless the controller adds, “expect to resume STAR”…” So this means that if you are in the USA and are given a vector off a SID/STAR after receiving a “Descend via or Climb via” pilots need to cancel compliance with all the rest of the required lateral, vertical and speed required by the SID/STAR.

That last bit about “Expect to resume the STAR” (or SID) is just a heads-up on what the controller is intending to do with your aircraft, it is not a clearance… yet. FAA air traffic control will use “Resume” phraseology with “Maintain” to rejoin a route and assign a new altitude where compliance with published altitude restrictions is not required. Once vectored back onto a SID/STAR waypoint and given a “Resume Descend/Climb via SID/STAR” only then does the rest of the procedure become required.

The FAA Defines the Differences in “Descend/Climb Via…”

In 2012 the FAA issued SAFO #12003. This directed pilots to be alert for phraseology differences when operating in Canadian Airspace (Think: ICAO procedures). The “CLIMB/DESCEND VIA…” phraseology indicates to pilots that compliance with the lateral, vertical and speed profile of the STAR is required.

Inside the USA/FAA: when vectored to a point off a “CLIMB/DESCEND VIA…” any published altitude, speed restrictions are cancelled unless reissued by ATC. The nuance here is that in the Canada/ICAO procedure, when vectored back onto the published SID/STAR... subsequent altitude, speed restrictions remain mandatory unless specifically cancelled by ATC. Jeppesen charting makes a note of this on Canadian STARS. Look for this verbiage as a reminder: "When a lower altitude is issued, pilots shall descend on the STAR profile to the ATC assigned altitude. Charted restrictions above the assigned altitude remain mandatory".


Specific Terminology is Important in “Descend/Climb Via…”

The problem for USA crews is when ICAO based ATC assigns an altitude, heading or speed following a “CLIMB/DESCEND VIA” that is not on the SID/STAR.

FAA controllers will use “Except… or “Except Maintain…” phraseology to modify published restrictions or assign a new altitude. ICAO controllers will use “Cancel Speed/Altitude Restriction at XYZ…” to specifically delete a speed/altitude restriction and name the points where these restrictions are deleted.

What Is the Same Across FAA and ICAO “Descend/Climb Via…”

The core phraseologies of “CLIMB VIA SID TO (level)” and” DESCEND VIA STAR TO (level)” require pilots to climb/descend to the cleared level in accordance with published lateral, vertical and speed restrictions.

Comply with published speed restrictions or ATC-issued speed control instructions as applicable unless specifically cancelled by ATC. ATC use of “CANCEL SPEED RESTRICTION” ICAO or “DELETE SPEED RESTRICTIONS” FAA applies only to the speed restrictions associated with the SID or STAR procedure. It does not cancel other speed restrictions such as 250KIAS/10,000MSL.

The requirement for a QNH altimeter setting to be included in the descent clearance when first cleared to an altitude below the transition level.

MEA’s are not considered restrictions. When vectored off a SID/STAR the controller is responsible for terrain clearance.

In unusual or unforeseen circumstances it may not be possible to apply the phraseology as intended. Should this happen, pilots and ATC personnel are still expected to use plain language, which must be as clear and concise as possible. 


Bottomline

  1. 1. Pilots need to be acutely aware of runway and SID/STAR transitions along with first waypoint coding on SID’s.
  2. 2. Published STAR lateral, vertical and speed requirements need to be compared to the local ATC clearance procedures.
  3. 3. Specific attention is required to the ATC usage of “Expect”, “Except…” and “Resume” terminology.

 

Where Can I Get More Information?

FAA

SAFO# 12003, Dated 5/26/16

AIM with Change #1, Dated 5/26/16, Paragraph 5-2-8, 5-4-1, 5-5-9

FAA Order 7110.65, Page 4-5-8, Paragraph 1

RNP Resource Guide, 4th Quarter 2016, Page #3 “Climb Via Video link”

Canada

TC Canada RAC, Paragraph 9.2.3

ICAO

For the document below, link here: http://www.icao.int/airnavigation/sidstar/Pages/CHANGES-TO-SID_STAR-PHRA-SEOLOGIES.aspx

State-letter-54_Amendment-7-to-PANS-ATM, PDF Pages 31-35

Sample Scenario Gouge

Communication Summary Leaflet