A quantum sensor has guided a ship across the Coral Sea with GPS switched off, in what the maker calls the first open demonstration of GPS-free quantum gravimetric navigation.
Q-CTRL said its software-ruggedized gravimeter mapped Earth’s gravity field and positioned the vessel to within one nautical mile during trials off Australia’s east coast. The system reads tiny variations in gravity rather than radio signals, making it immune to jamming and spoofing, the company said.
The demonstration lands as GPS interference surges worldwide. More than 978,000 jamming events were recorded in the first quarter of 2026 alone, 98% of them in the Middle East, where the Strait of Hormuz conflict has become a flashpoint for electronic warfare affecting more than 1,100 vessels.
The maritime variant belongs to Q-CTRL’s Ironstone Opal family, a line of quantum-assured navigation gear that derives position from Earth’s geophysical signatures. The company pitches the technology for air, land and sea as a fallback when satellite signals are blocked or unreliable. In the Coral Sea trials the system ran autonomously from a passenger cabin with no special cooling or stabilization.
The push drew praise from a retired Marine Corps general and a University of Liverpool professor, who called gravity-based navigation the only passive alternative that is global in reach and impossible to spoof. Q-CTRL holds contracts with DARPA, the Defense Innovation Unit, the Australian Defence Department and the UK Royal Navy.
