Simmonds Precision Products Inc. – SPPI

Simmonds Precision Products Inc. (SPPI) brings more than 80 years of expertise in the design, development, and integration of advanced aerospace sensing and gauging systems. As part of TransDigm Group Inc., SPPI supports a wide range of applications, including fuel management and vehicle health monitoring across commercial, military, and space platforms.
SPPI delivers advanced fuel measurement and gauging solutions for nearly every type of aircraft and space vehicle—from helicopters and fixed-wing aircraft to business jets and large commercial transports. Its systems are widely used by leading aerospace manufacturers, including Airbus and Boeing, underscoring a strong track record of reliability and performance.
The company also has deep heritage in cryogenic fluid measurement, with its technologies supporting liquid hydrogen (LH2) and liquid oxygen (LO2) applications in major space programs such as Apollo/Saturn V, Titan III/IV, and Space Shuttle. In addition, SPPI continues to validate its solutions with alternative aviation fuels to ensure safety, reliability, and efficient fuel management in evolving energy environments.
Beyond fuel systems, SPPI provides advanced Health & Usage Monitoring Systems (HUMS) and Integrated Vehicle Health Management (IVHM) solutions for rotorcraft and other aerospace platforms. These systems monitor hundreds of aircraft parameters through a network of sensors and onboard processing, enabling real-time insight into system performance and condition. The result is improved operational readiness, enhanced safety, and reduced maintenance costs.
With extensive experience in developing flight-critical software and integrating with modern avionics architectures, SPPI remains a trusted partner in delivering safe, efficient, and high-performance aerospace solutions.

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Role in COCOLIH₂T

Simmonds Precision Products Inc. (SPPI) is leveraging decades of aerospace sensing and fuel gauging expertise across commercial, military, and space platforms to develop a safe, reliable, and high-accuracy fuel gauging solution for hydrogen aviation systems. Through its role in the COCOLIH2T initiative, SPPI brings deep domain knowledge, building on its own state-of-the-art technologies to advance innovative LH2 gauging solutions.

SPPI leads LH2 gauging technology development within the Subsystem Development Work Package. The team is actively designing and manufacturing LH2 gauging prototypes, performing validation testing in laboratory environments using liquid nitrogen (LN2), and liquid hydrogen (LH2) testing in collaboration with Netherlands Aerospace Centre (NLR). In parallel, SPPI is contributing to modeling efforts to accurately predict system performance under LH2 conditions.

SPPI also plays a key role in supporting Demonstrator 2 activities at NLR, ensuring successful integration and validation of the LH2 gauging system. Beyond its subsystem leadership, SPPI contributes to several program work packages, including System Requirements and KPIs, System Integration and Demonstration, and Fuel System Health and Dissemination—leveraging its extensive experience to support overall program success.

Participating members in the project