There is so much about "Space Cowboys" that is unrealistic and, if you think about it, silly. But, it manages to tell this story in an entertaining fashion. So, my advice is just turn off your brain and enjoy.
The story begins in 1958. Despite all their training towards orbital travel, NASA is created and the Air Force folks who were working towards space were told to stand down. This part of the story is true and some of the pilots from all different branches of the military went on to become NASA astronauts. But some didn't...and the story now jumps to the present (2000). Frank (Clint Eastwood) is still rather bitter he never got a chance to go to space when his project for the Air Force was canceled...but now, in his senior years, an opportunity arises. A Soviet satellite is falling out of orbit and somehow the only person on a planet of 7,000,000,000 people who can fix it is Frank!! He insists that he doesn't want to tell a young astronaut how to fix it but will go to space himself...provided NASA also allows his three friends who were ALSO with project Daedalus to join him on the flight.
What follows are lots of old geezer jokes and montages. Eventually, the four guys are shot into space with two young hot shots. Unfortunately there are two huge problems. The satellite is NOT a communications satellite AND one of the crew members might just endanger millions because he's a horse's butt.
So is any of this believable? Not really. But it is engaging and the special effects quite amazing for 2000. My only real quibbles are that James Garner's character is poorly written, as he acts nothing like a Baptist minister (how many Baptist ministers say the Rosary as well as quote Alan Shepard instead of making a simple prayer??) and a lot of what surprises everyone in the film seems telegraphed. But the good far outweighs the bad and the picture is never dull.
