Ring Laser Gyro Gives us a Half-Million Reasons to Cheer!

Honeywell’s Navigation Sensors team in Minneapolis passed a major milestone recently when we produced and shipped the 500,000th unit of the 1320 ring laser gyroscope (RLG).   It is a historic feat to create a half-million of a single type of navigation-grade ring laser gyro.  But around Honeywell, no one is surprised given the legacy of one of the most innovative and reliable navigation aids ever invented.

If you’ve flown on a commercial or business aircraft, chances are your pilot relied on data from RLGs to get you to your destination. You’ll also find RLG-based navigation, stabilization, and pointing systems on military aircraft, land vehicles, and unmanned underwater vehicles for oil and gas exploration.

RLGs have out-of-this-world uses, too, providing precise position data for the International Space Station and NASA missions to explore Mars.  RLGs are scattered throughout our solar system, and some even exiting as they travel to the reaches of our outer space.  RLGs have safely navigated spacecraft to rendezvous with comets to collect cosmic dust samples.

These and other applications demonstrate the versatility of this remarkable device, which weighs about a pound and fits in the palm of my hand. But don’t let its modest size fool you. Honeywell engineers pack a lot of performance in a small and very efficient package.

Ring laser gyros are much more accurate than mechanical gyroscopes once used for navigation. They typically “drift” about 0.0035 degrees per hour, which equates to about a mile of drift per hour of flight, or about 8 miles after a transatlantic flight. RLGs are incredibly reliable, require very little maintenance by operators, and have a proven track record in safety-critical applications. RLGs are very rugged with respect to vibration and shock.

Mechanical or “spinning mass” gyros have been used in navigation since the early days of powered flight, and Honeywell was a major innovator and producer of mechanical gyros. We track our legacy back to the pioneering work of Elmer and Lawrence Sperry.

But mechanical gyros have their limitations, and the inquiring minds at Honeywell began looking for new and better alternatives. By the Fifties and Sixties, Honeywell researchers started work on a bold new approach to navigation, and after years of hard work, they finally “saw the light.” (Pun intended.)

Honeywell innovators were able to design one of the first RLGs, which used two laser beams traveling in opposite directions over a ring-shaped path formed by three mirrors. By measuring the frequency difference between the two beams, the gyro determines angular velocity and, ultimately, the direction the system is moving—simple, elegant, and groundbreaking.  Over the decades, Honeywell has refined this simple principle and pushed performance to the limits that quantum mechanics has allowed.

We produced our first RLG for the U.S. Navy in 1966 and continued to develop and refine the design throughout the 1970s, landing a major contract to equip the Boeing 757/767 with gyro-based navigation systems in 1978. From there, as they say, the rest is history.

While the principles used in the RLG haven’t changed much over the last four decades, Honeywell has dedicated itself to the continuous improvement of the technology and its applications. Today’s RLGs are smaller, lighter, more reliable, and more accurate than ever. They’re a preferred means of navigation for a wide range of platforms. The GG1320 RLGs have recorded an astounding 8 billion flight hours, more than any other inertial sensor on the market today – and they’re adding to that total every day.

As a physicist, it was love at first sight for me when I was asked to join the advanced sensing technologies team in 2014. Today I have the opportunity to work with an amazing group of Honeywell engineers, technicians, operators, and suppliers who have worked together – not just to achieve this historic milestone, but to deliver the best available inertial technology to improve the safety and efficiency of flight.

Amidst all the challenges with COVID-19 that we’re facing today, we still want to recognize this significant milestone.  And while it is hard to host a celebration with everything going on, it is certainly our intention to celebrate with the entire team as soon as we’re able.  In the meantime, the factory continues to build more and more RLGs as part of our commitment to sustain and support critical infrastructure manufacturing. 

Here’s to the next 500,000.