Triumph Group picks Green Hills real-time operating system (RTOS) for safety-critical helicopter avionics

April 12, 2024
Triumph also has selected the INTEGRITY-178 tuMP multicore RTOS for the company's next generation of quad-core-processing engine-control units.

RADNOR, Pa. – Engine-control experts at Triumph Group Inc. in Radnor, Pa., needed real-time software for a wide variety of U.S. military helicopter avionics. They found their solution from Green Hills Software in Santa Barbara, Calif.

Radnor experts chose the Green Hills INTEGRITY-178 real-time operating system (RTOS) for the engine-control units in U.S. helicopters including the AH-64D Apache, CH-47D/F & MH-47D/F/G Chinook, UH-60L/M/V Black Hawk, HH-60 Pave Hawk, MH-60 Jayhawk, and SH-60 Sea Hawk.

Safety-critical engine-control units running INTEGRITY-178 have been developed to RTCA/DO-178B design assurance level A (DAL A) avionics safety-assurance standard.

Triumph also has selected the INTEGRITY-178 tuMP multicore RTOS for the company's next generation of engine-control units, which has applications running concurrently on all cores of a quad-core processor.

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Those Triumph engine-control units rely on the multicore partitioning provided by INTEGRITY-178 tuMP to the same level as for single-core processors.

Triumph selected the INTEGRITY-178 RTOS for the security and determinism of the company's DAL A partition scheduler, the quality of its certification artifacts for RTCA/DO-178B DAL A, and the high productivity of its MULTI integrated development environment (IDE).

"Based on the consistent, trouble-free performance of the INTEGRITY-178 operating system over the past 20 years, Triumph continues to turn to Green Hills Software to support our current and future products," says Lou Pannullo, Director of advanced technology at Triumph.

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"INTEGRITY-178 and INTEGRITY-178 tuMP have continued to advance the state-of-the-art with unique multicore technology to meet our increased processing needs and by offering proven DO-178C/ED-12C and CAST-32A multicore artifacts to DAL A for the latest processors," Pannullo says.

Triumph uses the INTEGRITY-178 RTOS on the company's lines of engine-control units. Some Triumph engine-control unit models are full authority digital engine controls (FADECs), which have complete control of the engine without pilot backup.

The Triumph EMC-100 FADEC provides sophisticated, low-cost, dual-channel engine control in one housing. The unit consists of two dissimilar mechanically separated channels operating independently but cooperating with each other.

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The second channel provides mission capability should a failure occur in the primary channel. The software is organized in a multi-partition architecture, with application-specific control system software running in isolated partitions on the INTEGRITY-178 RTOS.

The engine-control unit software is designed to RTCA/DO-178B DAL A, but the software architecture permits partitions that perform non-critical functions to be developed to lower levels. The INTEGRITY-178 high-assurance RTOS also is deployed in the Honeywell flight control electronics for the Boeing 787 Dreamliner.

For more information contact Green Hills Software online at, or Triumph Group at

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