The first to suffer was NASA chief test pilot Joe Walker in his F-104N, as it rolled inverted across the back of the XB-70. The F-104’s T-tail ripped at the Valkyrie’s drooped right wingtip ...

Part Transformer, part Star Wars stormtrooper and with hands that look like they can crush beer cans, at 1.8 metres tall and weighing 120 kilograms, NASA’s Valkyrie robot is an intimidating figure.

NASA has built a 6ft 2in “superhero robot" that it named Valkyrie. Robots like this one may be the first to be sent to Mars before humans arrive on the Red Planet, says NASA's Nicolaus Radford.