This document provides aircraft installation requirements for a Low Frequency Underwater Locator Beacon (LF-ULB) transmitting on a frequency of 8.8 kHz. ICAO Annex 6 Amendment 36, states that a LF-ULB shall be installed on all aircraft with a maximum certified take-off mass of over 27,000 kg, operating over water at particular distances to land suitable for making an emergency landing. ICAO Annex 6 Amendment 36 further states that an LF-ULB shall be installed by January 1, 2018.