GEA 71H

The GEA 71 is a micro-processor based input/output Line Replaceable Unit (LRU) used to monitor
sensor inputs and drive annunciator outputs for aircraft airframe and engine systems. The GEA 71
interfaces with various sensors on the aircraft and communicates airframe and engine information via
RS-485 digital interface to GIA 63(W) Integrated Avionics Units or IAUs. The GIAs then interface with
the GDU Primary Flight Display(s) (PFD) and Multi-Function Display (MFD). Typically, the MFD
shows engine instrumentation while the PFD normally shows airframe alerts provided by the GEA 71.
Engine/airframe instrumentation is also displayed on the PFD and/or MFD while the system is in
reversionary mode. The PFD and MFD displays serve as the user interface for the GEA 71. All
configuration settings are controlled via software settings accessed by the MFD and PFD displays.
The GEA 71 uses a configuration module temperature sensor and a thermocouple sensor housed in a
backshell assembly to monitor backshell junction temperatures. This capability is only needed in the
event thermocouple engine temperature sensors are used.