Service and repair of the Breitling Cosmonaute
This vintage watch movement arrived in relatively good condition, but due to age the case and bezel were quite worn. The movement underwent a complete disassembly, ultrasonic cleaning, and oiling using high-quality synthetic watch lubricants, and was regulated, achieving a stable rate. However, the bezel teeth had suffered significant corrosion damage over the years. A mechanical repair was performed to stabilize the bezel, although it is no longer functional for rotation. Despite this limitation, the vintage watch restoration was a success and met the expectations of the owner.
If you would like to initiate the repair of your vintage timepiece, be sure to visit getting started. For additional information on watches we work on please visit these pages: Vintage Rolex repair, Vintage Breitling repair, Vintage Omega repair, and Vintage Heuer repair.















Origins
The Breitling Cosmonaute introduced in 1962. It was a variant of the Navitimer model. The Navitimer, introduced in 1952, was renowned for its functionality as a pilot’s watch, equipped with a slide rule bezel for performing crucial aviation calculations.
The Cosmonaute owes its development to Scott Carpenter, one of NASA’s original Mercury 7 astronauts. He requested Breitling to create a version of the Navitimer with a 24-hour dial instead of the standard 12-hour dial. He also requested a simplified slide rule to accommodate the needs of an astronaut, and wanted a wider bezel so it would easier to turn with large gloves on. Carpenter wore the Breitling Cosmonaute on May 24, 1962, during his mission aboard Aurora 7, making it one of the first wristwatches worn in space.
Evolution
Over the years, the Cosmonaute underwent several design and mechanical evolutions, though it retained its core identity as a watch designed for space exploration. Breitling has re-released the Cosmonaute in various limited-edition models, often celebrating the original design’s spacefaring heritage.
Design and Features
24-Hour Dial: The hallmark of the Cosmonaute is its 24-hour dial, where the hour hand completes one full rotation every 24 hours, unlike conventional watches which make two rotations every day.
Slide Rule Bezel: Like the Navitimer, the Cosmonaute retains the circular slide rule bezel, which allows the wearer to perform calculations related to aviation, such as fuel consumption, speed, distance, and unit conversions.
Chronograph Functionality: The watch is equipped with a chronograph function, allowing precise measurement of elapsed time. This model included a sweep seconds hand, a 30 min and a 12 hour timer.
The Movement
The early models of the Cosmonaute were powered by a manual-winding movement, such as the Venus 178. But this later variant uses the Heuer, Breitling, and Hamilton-Buren Cal 11 movement, one of the first automatic Chronograph movements that also includes a date function. See my post on the Breitling Navitimer for more information.