Boeing completed the world's first recorded flight test of multiple quantum sensors in 2024, enabling an airplane in flight to navigate without GPS for four hours.
While quantum sensors for navigation have been researched in laboratory settings for years, the test was the first known operation of the sensors on an airplane during flight. That and subsequent flights produced real-time navigation data, which is necessary to field any application of the technology.
Quantum navigation systems typically do not experience the temporary service interruptions that can occur with current GPS or other navigation systems. The accuracy of quantum navigation systems could allow commercial aircraft to navigate without GPS during their entire flight.
Measuring Success
The team conducted the test using a six-axis quantum inertial measurement unit (IMU). The IMU was integrated into a full inertial navigation system and deployed in a Beechcraft 1900D for the flight test series. A quantum IMU is designed to be more accurate than conventional IMUs. The improved accuracy can lead to reductions in navigation errors from tens of kilometers at the end of a long flight to just tens of meters.
The St. Louis flight test conclusively showed that the quantum sensors were able to operate successfully during takeoffs, landings and multiple maneuvers.
“Boeing is leading the development of quantum technology that will help improve flight safety,” said Ken Li, Boeing senior technical researcher and principal investigator for quantum navigation.
Quantum qualifications
Boeing collaborated with California-based AOSense to design and build the quantum IMU.
“We designed our quantum IMU for robust operation in harsh environments, and we are pleased to confirm that during flight testing the sensor performed along all input axes, as we anticipated,” said AOSense President Brenton Young. AOSense has been developing quantum sensors since 2004.
How works
The IMU uses a quantum sensing technique called atomic interferometry to detect rotation and acceleration using atoms, providing precision and accuracy navigation without a GPS reference.
The IMU consists of three quantum inertial sensors, each of which measures single-axis accelerations and rotations of the aircraft. The IMU tracks the path the aircraft has taken from its starting position. Boeing engineers integrated the quantum inertial sensors with additional sensors and hardware to ensure reliable in-flight performance. The result is the first known quantum-enabled navigation system of its kind.
Fast to quantum
“The ability to operate safely in GPS-deprived environments is critical for both commercial and defense applications,” said Todd Citron, Boeing’s chief technology officer. “This flight test showcases Boeing’s innovative approach to leveraging quantum technologies for operationally relevant challenges.”
Rapid iteration and testing allowed the Boeing and AOSense team to advance the technology from three single-axis sensors operating in a lab environment to a quantum IMU operating in flight in a period of just 15 months. During this time, the team conducted multiple lab, ground vehicle and flight tests, each focused on identifying improvements to increase the sensor’s capability and reliability.
“These rapid advances indicate great promise for quantum sensors to be part of the next generation of navigation sensors,” said Jay Lowell, Boeing Principal Senior Technical Fellow and quantum technology research manager. “This flight test is a historic first step in that direction.”
Star tracker
The flights also tested Boeing’s All Source Positioning, Navigation and Timing (ASPNT) software. The software combines information from multiple GPS-denied navigation detection modalities, including vision-based navigation, terrain-referenced navigation, gravity anomaly-referenced navigation, magnetic anomaly-referenced navigation, a star tracker, and signal of opportunity (SOOP) at multiple technology readiness levels.
In addition to the quantum IMU, the flights tested two other sensors: AQNav, a full-stack quantum navigation system from SandboxAQ, and a daytime-capable star tracker that Boeing developed with HRL Laboratories. Pairing AQNav with the star tracker was essential to the development of magnetic anomaly-referenced navigation technology.
The star tracker provided precise attitude and position references to flight testing. The star tracker’s shortwave infrared (SWIR) technology is also a unique development. Compared to star trackers used in military systems 50 years ago, the Boeing-designed system is smaller, weighs less, uses a fraction of the power and achieves better performance.
Two telescopes, along with SWIR cameras, form the main part of the star tracker. The star tracker is mounted next to a custom window that is transparent to SWIR light, making the star tracker operable.
Magnetic measurement
AQNav uses the Earth’s magnetic field to compare real-time measurements to a pre-mapped magnetic field. This approach, combined with IMU data, significantly anchors IMU drift by limiting potential navigation errors through a process that correlates the aircraft’s trajectory with observed magnetic data.
AQNav helps ensure that navigation deviations remain within an operational margin. This results in a highly reliable and accurate alternative navigation system that effectively reduces the accumulation of errors over time, which is critical for flying in areas where GPS signals are not available. Designed to be uninterrupted, tamper-proof, 24-hour, all-weather and terrain-independent, AQNav is a ive technology that operates in the background without interaction.
“Rapid progress has been greatly accelerated thanks to Boeing’s collaborative approach and its exceptional integration capabilities with SandboxAQ,” said AQNav Senior Hardware Engineer Eddie Rodriguez. “This strong partnership, combined with our expertise in AI modeling, has enabled us to deliver an enhanced system and demonstrate its capabilities in just six months.”
What comes next
Boeing will conduct a series of laboratory tests to help understand how the IMU quantum navigation sensors perform under certain environmental conditions, such as temperature and vibration. These tests will provide data for Boeing and AOSense engineers to improve the performance, robustness and reliability of the quantum navigation system. IQ
By Mychaela Kekeris of Boeing
