The B-52 took to the skies Tuesday, but no other information about the test flight was available, John Haire, a spokesman for Edwards Air Force Base in California, said in an email.

MSN: Hypersonic aircraft taken out for a trial run on B-52 bomber

But Mr Aldrin disagreed with the view that astronauts should test capabilities for a long-duration flight on the Moon before attempting a journey to Mars.

BBC: Moon astronauts urge Mars mission

Like Amazon, the company is secretive, but last September it revealed that it had lost an unmanned prototype vehicle during a short-hop test flight.

ECONOMIST: Brain scan

Few details were released about the flight, made Saturday, but the test indicates China's ambitions to add a heavy freighter to its capabilities and match better against traditional air powers, Russia and the United States.

CNN: China's new super cargo jet takes to the skies