Electronic Standby Instrument Systems

The thinnest and widest remote-mounted standby for business and commercial aircraft

At only 1.5 inches deep, the L3 GH-3900RSU™ Electronic Standby Instrument System (ESIS) is the thinnest electronic standby instrument available for business, regional and commercial aircraft and helicopters. Highlighting the system’s design is a Remote Sensor Unit (RSU) which enables the 4.2-inch (diagonal) landscape display to be installed virtually anywhere on the panel. The GH-3900RSU ESIS is designed to meet the needs of Part 23 (Class III & IV), Part 25 aircraft and Part 27 and Part 29 helicopters.

Two pieces mean one flexible solution

The two-piece design of the GH-3900RSU gives aircraft designers and avionics installers the greatest possible flexibility when it comes to the display’s location. Because the RSU houses the rate/level sensors, air data transducers and optional accelerometers, the panel display needs to be only 1.5 inches deep.

User defined display configurations

The GH-3900RSU allows the avionics installer to easily define data I/O interface, Static Source Error Correction (SSEC) and Velocity Maximum Operation (VMO) values, along with customizing the display parameters to meet individual requirements.

DU-42 Display GH-3900RSU Remote Sensor Unit
Dimensions (L x W x H)* 1.50 in. x 5.25 in. x 3.00 in.
(38 mm x 133 mm x 76 mm)
8.32 in. x 3.19 in. x 3.35 in.
(211 mm x 81 mm x 85 mm)
Weight 1.5 lb. max (0.68 kg) 3.0 lb. max (1.36 kg)
Interfaces • ARINC 429 Inputs (3) and Output (1)
• USB Serial Bus (1)
• RS-232 Serial Bus (1)
• I2C Serial Bus (1)
• Analog Input (1)
• ARINC 429 Inputs (7) and Outputs (3)
• RS-422 Serial Bus (1)
• RS-232 Serial Bus (1)
• Discrete Inputs (6) and Outputs (2)
• Analog Inputs (2)
• Pneumatic Pressure Ports
Power +28 VDC, nominal +28 VDC, nominal
Certifications TSO-C2d, C3e, C4c, C6e, C8e, C10b, C34e, C35d, C36e, C40c, C46a, C66c, C95a, C106, C113a TSO-C2d, C3e, C4c, C6e, C8e, C10b, C46a, C95a, C106
Software/Firmware DO-178B Level B / DO-254 Level B DO-178B Level A / DO-254 Level A

*Excluding knob and connector

Product Support

Technical Support:
Email: FieldService.Avionics@L3T.com
Phone: +1 (616) 949-6600
AOG Hotline: +1 (800) 453-0228 or +1 (616) 949-6600
Ft. Lauderdale AOG: +1 (954) 629-8689

Repair and Overhaul Administration:
Email: service.avionics@L3T.com
Phone: +1 (800) 253-9525
Fax: +1 (616) 977-6895

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