I've been looking for this movie for years. I think it was made in the 70's or possibly even before that: The US govt only pretends to send a spaceship to the moon, or Mars, but in reality they stage the whole thing on Earth. In the meantime, the real crew of the spaceship gets dropped off somewhere in the desert where one by one they are hunted down and killed so they cannot reveal the deception.

Capricorn One (1978) (http://www.imdb.com/title/tt0077294/)

And it was an awesome movie, too.

I enjoyed watching that movie. Classic!