Vulcan Centaur returns to flight with upgraded boosters after nozzle failures

United Launch Alliance's Vulcan Centaur rocket is launching today for the first time in nine months, carrying 40 Amazon Leo internet satellites. This marks the rocket's fifth flight overall but comes after a period of intense scrutiny. The Vulcan experienced issues on two previous missions where solid rocket booster nozzles burned through and detached shortly after liftoff, though both flights ultimately succeeded.

The U.S. Space Force paused national security launches on Vulcan until the problem was addressed, prompting ULA to redesign the nozzle. Today's flight will use the improved booster design, serving as a crucial validation test. The successful return to flight is essential for ULA's future manifest and for building out Amazon's satellite internet constellation to eventually compete with SpaceX's Starlink.