I'm just getting started so I'm sure bigger fails are in my future but: I was returning Bob, Jeb, and Bill from my first successful moon landing. Got back into orbit around Kerbin and started my reentry. I decided to get a screen shot from Bob's point of view during the reentry. WHY are the EVA and IVA buttons are RIGHT NEXT TO EACH OTHER? Yes, I accidentally sent Bob out of the hatch as the flames of reentry engulfed the capsule. It did not go well for him. At this point I just wanted to get Jeb and Bill home so they could mourn him properly. I got down to 1000 feet, popped the chute - and got a linkage failure between the chute and capsule. The chute tore away and the capsule smashed to Kerbin doing several hundred meters per second, killing Jeb and Bill instantly.