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GH-3900RSU Electronic Standby Instrument System (ESIS)

Product overview

At only 1.5 inches deep, the L3Harris GH-3900RSU™ Electronic Standby Instrument System (ESIS) is the thinnest and widest 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 27/29 rotorcraft.

Key features

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 its location. Utilizing a two-part system design that separates the display from the sensor array, the 1.5-inch-deep unit can be installed almost anywhere behind the aircraft's panel, even in areas with limited space.

The GH-3900RSU, which houses rate/level sensors, air data transducers and optional accelerometers, delivers attitude, altitude, airspeed and navigation data to the high-resolution wide-screen DU-42 display, ensuring pilots will have the critical information they need in case of main instrument system failures. Heading data is also available using an ARINC 429 source or the L3Harris MAG-3000 magnetometer.


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.

Product specifications

DU-42 Display

1.50 in. x 5.25 in. x 3.00 in.
(38 mm x 133 mm x 76 mm)

*Excluding knob and connector

WEIGHT 1.5 lb. max (0.68 kg)
  • ARINC 429 Inputs (3) and Output (1)
  • USB Serial Bus (1)
  • RS-232 Serial Bus (1)
  • I2C Serial Bus (1)
  • Analog Input (1)
POWER +28 VDC, nominal
CERTIFICATIONS TSO-C2d, C3e, C4c, C6e, C8e, C10b, C34e, C35d, C36e, C40c, C46a, C66c, C95a, C106, C113a
SOFTWARE/HARDWARE DO-178B Level B / DO-254 Level B

8.32 in. x 3.19 in. x 3.35 in.
(211 mm x 81 mm x 85 mm)

*Excluding knob and connector

WEIGHT 3.0 lb. max (1.36 kg)
  • 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
CERTIFICATIONS TSO-C2d, C3e, C4c, C6e, C8e, C10b, C46a, C95a, C106
SOFTWARE/HARDWARE DO-178B Level A / DO-254 Level A


  • GH-3900RSU ESIS Datasheet


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