This is an installation manual that introduces the installation method of GRS 77/GMU 44
This document provides step-by-step instructions for installing the Garmin GRS 77 and GMU 44 units in aircraft. It covers unpacking, electrical connections, mounting, and calibration procedures. Detailed wiring diagrams and installation drawings are included in the appendices. The guide also addresses aircraft-specific mounting requirements and interference testing for magnetometer calibration.
The manual includes hardware modification levels and service bulletins for different unit revisions, ensuring compatibility and reliability. It is intended for technicians and installers working with avionics systems, with specific sections for fixed-wing and helicopter installations.
| System SW Version | 3.00 for GRS 77, 3.50 for GRS 77H, 2.05 for GMU 44 |
|---|---|
| Hardware Mod Levels | Mod Levels listed for GRS 77 and GMU 44 with service bulletin numbers and purposes |
GRS 77 (011-00868-00 and 011-00868-10) has System SW Version 3.00, GRS 77H (011-00868-20) has 3.50, and GMU 44 (011-00870-00 and 011-00870-10) has 2.05.
It is an aviation attitude and heading reference system.
The revision date is March, 2010.
The GRS 77H unit part number is 011-00868-20.