https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_20-18B.pdf
Subject: Qualification Testing of Turbojet and Turbofan Engine Thrust Reversers
Date: July 7, 2015 AC No: 20-18B
Purpose. This advisory circular (AC) provides guidance for demonstrating compliance with Title 14 of the Code of Federal Regulations (14 CFR) 33.97, Thrust reversers, and for certifying a thrust reverser for use with a turbojet or turbofan engine. It does not address aircraft-level effects of the installation and use of a thrust reverser.
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