Interpretation 11

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  • Date of Interpretation Applicable 7110.65 section
    12/1/2015 4-5-7

    Background Information

    This is in response to a request for interpretation submitted by the Central Service Area, on behalf of Indianapolis Air Route Traffic Control Center (ZID), regarding JO 7110.65, paragraph 4-5-7, Altitude Information.


    At what point do published speed restrictions on Optimal Profile Descent (OPD) / Descend Via procedures become mandatory?


    ZID’s concern is that the language found in JO 7110.65 paragraph 4-5-7h is contradictory. The language in question is underlined:

    Issue altitude instructions as follows:
    h. Instructions to vertically navigate on a STAR/SID with published restrictions.
    NOTE –
    When cleared for STARs that contain published speed restrictions, the pilot must comply with those speed restrictions independent of any descend via clearance.
    Clearance to “descend via” authorizes pilots:

    1. To descend at pilots discretion to meet published restrictions and laterally navigate on a STAR. Pilots navigating on a STAR must maintain the last assigned altitude until receiving clearance to descend via. Once departing an altitude, the pilot may not return to that altitude without an ATC clearance.
    2. When cleared to a waypoint depicted on a STAR, to descend from a previously assigned altitude at pilot’s discretion to the altitude depicted for that waypoint. ATC assigned altitudes must ensure obstacle clearance.
    3. Once established on the depicted arrival, to descend and to meet all published or assigned altitude and/or speed restrictions. Where speed restrictions are published at the waypoint/fix, pilots will begin slowing to comply with the restrictions prior to reaching the waypoint/fix.
    ZID’s contends the language in the 3rd subparagraph of the Note, “Once established on the depicted arrival” implies that published speed restrictions on an OPD procedure are required only after the “descend via” clearance has been issued; hence the reference “Clearance to descend via authorizes pilots.

    After reviewing the referenced documents, the Air Traffic Procedures Group finds no contradiction in JO 7110.65, paragraph 4-5-7h. A clearance to descend is not a prerequisite for compliance to published speed restrictions on a Standard Terminal Arrival Procedure (STAR). Pilots navigating STARs that contain published speed restrictions are required to comply with those speed restrictions in the absence of, or regardless of the type of descent clearance. The three subparagraphs in the Note simply describe what is expected of a pilot after being cleared to descend via.

    Additionally, the Aeronautical Information Manual Chapter 5, section 4, paragraph a1 states: “Published speed restrictions are independent of altitude restrictions and are mandatory unless modified by ATC.”

    Therefore, the language in the three subparagraphs of the Note must not be considered as qualifying conditions or exceptions to the requirement of the Note in Paragraph 4-5-7h, which states: “When cleared for STARs that contain published speed restrictions, the pilot must comply with those speed restrictions independent of any descend via clearance.”
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