Q-CTRL has reported the first open-water field demonstration of a quantum gravimetric navigation system capable of operating without global navigation satellite system (GNSS) signals. The company's Ironstone Opal platform was deployed aboard a 29-meter vessel in the Coral Sea, off the eastern coast of Australia, where it maintained bounded position accuracy within 1 nautical mile over an 83-kilometer trajectory. This performance, achieved without access to satellite navigation, represents a more than tenfold improvement over standard navigation-grade inertial backup systems under similar conditions.

Hybrid Quantum-Classical Sensing
The Ironstone Opal system integrates a hybrid sensor architecture, combining cold-atom interferometry with classical accelerometers. Cold-atom gravimeters exploit the quantum interference of ultracold atoms to measure local gravitational acceleration with high precision, while classical accelerometers provide continuous inertial data. In this field trial, the quantum sensor was installed in an unconditioned passenger cabin, operating without active environmental temperature control or heavy motion-stabilization platforms. The system's AI-driven software stabilized the quantum measurements under open-ocean wave conditions, enabling both gimbaled and rigid strapdown deployments to achieve comparable results.