By that same principle, there is a 50/50 chance that you even get off the ground (plane takes off/plane fails to take off). So your chances of crashing are actually only 1 in 4.
Then there's also your chances of getting to the airport on time in the first place, which is, let's say, 1 in 4. And that you'll find a parking space less than a mile away... oh, that's like 1 in 100. So, really, the odds that you will die in the plane crash are MUCH lower.