Northrop Grumman Delivers Next-Gen Resilient Navigation for US Jets

SANTA BARBARA, CA – April 28, 2026 – In a significant step toward modernizing the U.S. military's airborne capabilities, Northrop Grumman has delivered the first production unit of its LN-351 Embedded Global Positioning System/Inertial Navigation System-Modernization (EGI-M). This advanced system, slated for initial deployment on the F-22 Raptor and E-2D Advanced Hawkeye aircraft, is designed to ensure that America's most advanced warplanes can navigate with precision even when GPS signals are jammed, spoofed, or entirely unavailable.

At the heart of this resilient navigation solution is the INTEGRITY®-178 tuMP™ real-time operating system (RTOS) from Green Hills Software, a company renowned for its high-assurance embedded systems. The selection highlights a critical trend in modern defense: the increasing reliance on sophisticated, certified software to counter the growing threats of electronic warfare and maintain operational superiority in contested environments.

A New Era of Resilient Navigation

The EGI-M is more than just an incremental upgrade; it represents a fundamental shift in how military aircraft establish their position, navigate, and time their operations. The system's core strength lies in its ability to operate effectively in GPS-denied or constrained environments. It achieves this by tightly integrating an advanced inertial navigation system (INS), which uses fiber-optic gyros and accelerometers to track motion, with a next-generation M-Code capable GPS receiver.

M-Code, or Military-Code, is a powerful, encrypted GPS signal broadcast from the latest generation of GPS III satellites. It is significantly more resistant to jamming and spoofing than the legacy signals used by both military and civilian receivers. This capability is crucial, as adversaries have demonstrated a growing proficiency in disrupting standard GPS, a vulnerability that could cripple operations reliant on precise navigation and timing.

When GPS signals are unreliable, the EGI-M’s high-precision INS takes over, providing a highly accurate navigation solution that allows pilots to continue their mission and accurately deploy weapons. This fusion of technologies ensures that platforms like the stealthy F-22 can penetrate contested airspace with confidence, while the E-2D Hawkeye can maintain its crucial role as an airborne early warning and command-and-control hub. The system's design provides four independent navigation solutions, giving aircrews unparalleled assurance in the integrity of their positioning data.

The Unseen Engine: High-Assurance Software

While the hardware is impressive, the reliability and security of the EGI-M depend on its software foundation. Northrop Grumman’s choice of the INTEGRITY-178 tuMP RTOS running on a quad-core ARM Cortex-A53 processor was driven by the system's stringent safety and security requirements. In the world of avionics, software failure is not an option, and Green Hills Software has built its reputation on meeting the highest levels of certification.

Key to its selection was the RTOS's unique combination of certifications. It is compliant with DO-178C Design Assurance Level A (DAL-A), the highest level of safety criticality for airborne software, which is essential for flight-critical systems. Simultaneously, it boasts a proven Multiple Independent Levels of Security (MILS) architecture and has achieved a Common Criteria EAL 6+ 'High Robustness' security certification—the highest level ever awarded to a software product. This dual focus ensures the system is not only safe from malfunction but also secure from cyber threats.

“Green Hills Software is proud to support Northrop Grumman on the EGI-M program for their safety and security requirements,” said Dan O’Dowd, founder and chief executive officer of Green Hills Software. “The INTEGRITY-178 tuMP RTOS has a unique combination of safety and security in a single MOSA product. Designed from the beginning to be a multicore RTOS, INTEGRITY-178 tuMP is the only FACE conformant RTOS that has the ability to run a DAL-A partition across multiple cores and mitigate all sources of multicore interference per AC 20-193.”

The mention of multicore interference is critical. Modern processors use multiple cores to increase performance, but this creates a challenge for safety-critical systems: applications running on different cores can interfere with each other by competing for shared resources like memory. The FAA’s AC 20-193 advisory provides a path to mitigate this risk. INTEGRITY-178 tuMP was the first RTOS to be part of a successful multicore certification to these rigorous standards, ensuring that an application's performance remains deterministic and reliable, regardless of what other applications are doing on the processor.

Open Standards and Rapid Response

The EGI-M program also exemplifies a major strategic push by the Department of Defense (DoD) toward a Modular Open Systems Approach (MOSA). The system's architecture is designed to conform to the Future Airborne Capability Environment (FACE®) 3.0 Technical Standard, which promotes software interoperability and reusability across different military platforms.

This open architecture is a game-changer for defense procurement. In the past, avionics systems were often proprietary, “black box” solutions, making them expensive and slow to upgrade. A new threat might require a years-long, multi-million-dollar development contract with the original vendor to update the system’s software.

With a FACE-conformant architecture, the EGI-M provides a Common Application Space (CAS) that allows the DoD or third-party vendors to rapidly develop and integrate new applications—such as alternative navigation sources or advanced threat-detection algorithms—without deep involvement from Northrop Grumman. This accelerates the pace of innovation, increases competition, and dramatically reduces the cost and time required to respond to emerging battlefield challenges. By embracing open standards, the military can ensure its platforms remain technologically superior throughout their service life.

Strategic Impact on Contested Airspace

The delivery of the first production EGI-M unit marks a key milestone in a long-term, multi-billion-dollar effort to secure the U.S. military's access to trusted Positioning, Navigation, and Timing (PNT). The Pentagon has identified resilient PNT as a top priority, recognizing that the strategic advantage provided by GPS is under constant threat. The EGI-M is a direct answer to that challenge and is expected to be integrated into a wide range of aircraft beyond the F-22 and E-2D, including helicopters, cargo planes, and unmanned aerial vehicles.

This technology provides more than just a backup for GPS. It enables a more aggressive and flexible operational posture. Aircraft equipped with EGI-M can operate with greater confidence in heavily defended areas, sustain operations during prolonged electronic warfare attacks, and ensure the precision of long-range strikes. As nations continue to develop sophisticated anti-access/area denial (A2/AD) capabilities, this ability to navigate resiliently becomes a cornerstone of projecting air power.

The broader trend is a move toward a multi-layered PNT architecture, where GPS is one of many tools in the navigation toolbox. The EGI-M's open design is perfectly suited for this future, allowing for the future integration of celestial navigation, signals of opportunity, and other non-GPS sensors. This ensures that even if one source of positioning data is compromised, U.S. and allied forces will retain the ability to navigate accurately and maintain a decisive operational edge in an increasingly complex and contested global landscape.