Vulcan Centaur's launch delayed to Q4 2023 due to mishap."

"Vulcan Centaur's Cert-1 vehicle safe but requires adjustments."

"Hydrogen leak during testing caused explosion, delayed launch."

"Leak in the hydrogen tank due to weld failure."

"Reinforcing the dome design to rectify leak issues."

"Centaur 5 fix underway, Cert-1 flight in Q4 2023."

"Vulcan Centaur's BE-4 engine failure not a concern."