built, but initially skeptics wondered if it would even work. i remember sitting in the grandstand here at the press site talking to my colleagues and saying it won t work. it s too complicated. this, this is a disaster in the making. reporter: on april 12, 1981, veteran astronaut john young and pilot bob clippen were ready to prove nasa s critics wrong. they were chosen to take the shuttle into space. clippen reflected on that date during our recent phone interview. how my name came out of the hat has never been quite clear to me, but i m really proud that it did. it was just pure excitement. didn t have time to be scared. reporter: with the world watching, they set off on a two-day test flight. i turned to john, and i said i think we might do it, and that s when my heart rate went up to about 130. his was a nice, calm 90. i m really surprised mine didn t go any faster. reporter: together they