All eight crew members aboard a US Air Force B-52 Stratofortress bomber were killed when the aircraft crashed during takeoff at Edwards Air Force Base in California on Monday, Air Force officials said.
The plane crashed after having taken off from the base, located in California, at 11:20 a.m. local time.
Air Force officials said the bomber was conducting a routine test mission in support of a radar modernization program when it crashed immediately after leaving the ground.
The cause of the crash remains under investigation.
"Emergency crews immediately responded to the scene, and the situation is ongoing," the base wrote in a post on X/Twitter.
The crash occured at 11:20 a.m. local time, according to the base.
The eight-engined strategic bomber has been in service for over 70 years, with current engineering analyses indicating the aircraft's lifespan will extend past 2040, according to the US Air Force Strike Command's website.
Large, high-flying bomber
With a wingspan of 185 feet (56.4 meters), the B-52 can be equipped with the widest array of weapons in the US military's inventory, the website said.
According to the website, the aircraft is capable of flying at high subsonic speeds at altitudes up to 50,000 feet (15,166.6 meters) and can carry both nuclear and conventional ordinance.
In a conventional conflict, the B-52 can perform strategic attack, close-air support, air interdiction, offensive counter-air and maritime operations, the fact sheet said.
Monday's incident marked the first crash of a B-52 Stratofortress since the same type of bomber crashed on the island of Guam in May 2016, according to the Bureau of Aircraft Accidents Archive, a Geneva-based organization that collects global aviation accident data. All seven crew members aboard that aircraft survived.
Cause under investigation
Air Force Colonel James Hayes told reporters that the aircraft carried a mixed crew of military personnel, government civilians and contractors. Officials have not released the identities of the victims, saying families were still being notified.
"After reviewing footage of the crash, it was deemed to be unrecoverable and unsurvivable," Hayes said.
Because of damage to the runway, Edwards Air Force Base suspended flight operations through at least Tuesday, Hayes said.
Only the H model of the B-52 remains in the Air Force inventory and is assigned to the 5th Bomb Wing at Minot Air Force Base in North Dakota and the 2nd Bomb Wing at Barksdale Air Force Base in Louisiana, both under the Air Force Global Strike Command, and to the Reserve Command's 307th Bomb Wing at Barksdale, according to the military.
The aircraft involved in Monday's crash was assigned to the 412th Test Wing, which is based at Edwards Air Force Base.