Aircraft Operations Above 25,000 Feet MSL / Mach Numbers Greater Than .75
Operations above 25,000 feet MSL or Mach 0.75 — high-altitude physiology, pressurization, and high-speed aerodynamics.
About this document
AC 61-107, Aircraft Operations at Altitudes Above 25,000 Feet MSL or Mach Numbers Greater Than .75, provides guidance on the high-altitude and high-speed environment. It covers high-altitude physiology (hypoxia, decompression, use of oxygen and pressurization), the aerodynamics of high-speed flight (Mach effects, Mmo), and the training the FAA recommends before operating in this regime.
It supports the high-altitude endorsement and is relevant to Commercial and ATP knowledge.
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Take a free practice test →AC-61-107 is an official FAA publication in the public domain. We host a copy so you can read it in-browser; always confirm you are reading the current edition on faa.gov. The description above is an original summary and is a study aid, not a substitute for the document or the regulations.