For an example of the precision that was possible see: “B-52H Aircraft Mishap Report,
4 October 1968”
(Headquarters, Air Force Safety Center, Judge Advocate Mishap Records Division [AFSC/JAR], Kirtland AFB, NM). The TRANSCRIPTION OF RECORDED CONVERSATIONS begins when the B-52 (FOG 31) is approximately 600 miles east of Minot, under control of Minneapolis, and subsequently Great Falls Air Route Traffic Control Centers (ARTCC). It covers a period of time from 0256-0852Z before passing to Minot approach control. [Note: this document is in two parts in reverse order.]
The AIRCRAFT ACCIDENT TRANSCRIPTION-MINOT APPROACH CONTROL covers the period from 0842-0907Z. The communications span a period of 6 hours, the jargon is accurate, and time references are precise to increments of seconds.