The U.S. Air Force has grounded all its B-1 bombers as of June 7, following issues with ejection seat components.

A U.S. Air Force B-1B Lancer, assigned to the 37th Expeditionary Bomb Squadron, deployed from Ellsworth Air Force Base, South Dakota, prepares to take off from Andersen AFB, Guam, Sept. 23, 2017. This mission was flown as part of the continuing demonstration of the ironclad U.S. commitment to the defense of its homeland and in support of its partners and allies. (U.S. Air Force photo/Staff Sgt. Joshua Smoot)
The Air Force Global Strike Command ordered the safety stand-down of the B-1B Lancer fleet as of June 7, the Air Force announced in a release.
Air Force Global Strike Command has ordered its B-1 bombers to stand down after finding ‘an issue with ejection seat components’ https://t.co/IfLN1kI3qq
— Business Insider (@businessinsider) June 8, 2018
“During the safety investigation process following an emergency landing of a B-1B in Midland, Texas, an issue with ejection seat components was discovered that necessitated the stand-down,” the Air Force said. “As issues are resolved, aircraft will return to flight.”
Air Force grounds B-1 bombers after ejection seat incident https://t.co/2aR8oCONrO pic.twitter.com/mR7BAW0L0J
— Washington Examiner (@dcexaminer) June 8, 2018
There is an ongoing Safety Investigation Board (SIB).

B-1B Lancer bombers flanked by USMC F-35 Lightning II and JASDF F-2 fighters execute a bilateral mission over the Pacific Ocean, demonstrating the United States’ ironclad commitment to our allies in the face of aggressive and unlawful North Korean missile tests. (Courtesy Photo by Japan Air Self Defense Force/Released, by Japan Air Self-Defense Forces)
“The SIB’s purpose is to prevent future mishaps or losses and is comprised of experts who investigate the incident and recommend corrective actions,” the Air Force said. “The safety of Airmen is the command’s top priority. The Air Force takes safety incidents seriously and works diligently to identify and correct potential causes.”