I just remembered (and wonder how I forgot in the first place). Back in 'bout '66 or so, I was the only one on duty one night at a little bitty Army Airfield when a U-1A (DeHavilland Otter) took off on a rare night mission. The aircraft broke ground, started to climb, then banked steeply to the left, nosed over, and crashed alongside of the runway. Aircraft burnt to a crisp, but the three on board got out, with the worst injury a broken ankle. Results of the post crash investigation? The pilot failed to remove a clip from the rudder prior to takeoff. So when the engine failed (don't think they ever figured out why), and the aircraft banked to the side, the pilot could not control it enough to set back down on the runway. Which makes me wonder if the pilot in this case missed some part of a checklist...