Trilogy™ Electronic Standby Instrument (ESI)

A digital revolution in standby instrumentation

Whether you fly a Part 23 fixed-wing aircraft or a Part 27/29 rotorcraft, the pathway to a complete glass package leads to the L3 Trilogy™ Electronic Standby Instrument (ESI).  The Trilogy ESI is a panel-mounted solid-state instrument that provides dependable backup for attitude, altitude and airspeed information. The Trilogy ESI replaces traditional electro-mechanical standby instruments and combines the information into a compact and easy-to-read 4-inch x 3-inch display.

Trilogy ESI Key Features:

  • Internal battery (ESI-2000 model) provides flight data for a minimum of one hour after power loss
  • Logically grouped flight data eliminates multiple instruments, making the transition to standby easier
  • Single instrument reduces weight and scan times vs. reading multiple instruments
  • Certified to Design Assurance Level A, the highest safety standard acknowledged by the FAA

Ideal solution for new aircraft, veteran fleet

The Trilogy ESI’s space-saving footprint, easy installation and complete digital design make it the ideal standby for both new aircraft as well as those outfitted with aging or traditional analog gauges. Heading is also available, when coupled with the optional magnetometer, which enables the system to display magnetic heading in a dedicated window.

Case-contained design

If you’re planning a panel upgrade, now is the perfect time to add a Trilogy ESI. Trilogy’s internal, long-lasting lithium-ion battery (ESI-2000 model) and case-contained design makes installation straightforward and affordable for almost any fixed-wing or helicopter platform.

Liquid Crystal Display, flicker-free LED backlight

The Trilogy ESI’s Active Matrix Liquid Crystal Display (AMLCD) has a nominal diagonal size of 3.7 inches with a flicker-free LED backlight. A bezel-mounted light sensor provides automatic dimming with manual adjustment controlled via the menu system. Four soft key buttons on the front of the bezel provide quick access to user-defined display settings, barometric adjustments and menu options. The Trilogy bezel is available in gray or black.

Size (W x H) Bezel: 4” x 3” (10.16cm x 7.62cm)
Chassis: 3-ATI Opening
6.17 in. deep (15.67 cm)
Weight ESI-1000: 2.22 lb. (1.01 kg) max ESI-2000: 2.56 lb. (1.16 kg) max
Power +28.0 VDC nominal, 10.0 watts max
+14.0 VDC (with external converter)
Environmental DO-160F
Hardware DO-254, Level A
Software DO-178B, Level A
Performance Altitude: -1,500 ft. to +55,000 ft.
Airspeed: 20 knots to 400 knots
Certification FAA and EASA TSO-C2d, TSO-C3e, TSO-C4c, TSO-C6e, TSO-C10b, TSO-C46a, TSO-C113, TSO-C179
Vibration Tested to fixed-wing and helicopter vibration levels per DO-160F

Product Support

Technical Support:
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:
Phone: +1 (800) 253-9525
Fax: +1 (616) 977-6895

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