Skip to Content

We invite you to try out our new beta eCFR site at We’ve made big changes to make the eCFR easier to use. Be sure to leave feedback using the 'Feedback' button on the bottom right of each page!


Change in EST Usage in Notice to Airmen (NOTAM)

Document Details

Information about this document as published in the Federal Register.

Document Statistics
Document page views are updated periodically throughout the day and are cumulative counts for this document. Counts are subject to sampling, reprocessing and revision (up or down) throughout the day.
Published Document

This document has been published in the Federal Register. Use the PDF linked in the document sidebar for the official electronic format.

Start Preamble


Federal Aviation Administration (FAA), DOT.


Policy change.


This document provides clarity and guidance regarding the use of the contraction “EST”, which stands for “Estimated”, when appended to the end of validity time in a NOTAM. The FAA is taking this action to align NOTAM policy with International Civil Aviation Organization (ICAO) standards and recommended practices.


Effective date: December 15, 2015.

Start Further Info


Gary Bobik (202-267-6524; or Lynette Jamison (540-422-4761;

End Further Info End Preamble Start Supplemental Information



The Federal Aviation Administration (FAA) Flight Services is revising FAA Order JO 7930.2, Notices to Airmen (NOTAM), which is scheduled to become effective no later than December 15, 2015.

The following paragraphs will be incorporated into the next revision of FAA Order JO 7930.2.

Paragraph 4-2-1a-14, Start of Activity/End of Validity, is “a 10-digit date-time group (YYMMDDHHMM) used to indicate the time at which the NOT AM comes into force (the date/time a condition will exist or begin) and the time at which the NOTAM ceases to be in force and becomes invalid (the expected return to service, return to normal status time, or the time the activity will end).”

Paragraph 4-2-1a-14(a) further specifies, that if the NOTAM duration is expected to return to service prior to the End of Validity time, express the time by using a date- time group followed immediately by EST. The NOTAM Originator must cancel or replace any NOTAM that includes an EST before the NOTAM reaches its End of Validity time, as the NOTAM will now auto expire at the end of validity time, regardless of EST.

Start Signature

Issued in Washington, DC, on September 23, 2015.

Ernie Bilotto,

Manager, U.S. NOTAMs.

End Signature End Supplemental Information

[FR Doc. 2015-25192 Filed 10-2-15; 8:45 am]