Sorry to hear of the crash David, it is a sobering reminder that even during pre flight checks it is easy to become so conditioned to going through the motions that sometimes we look but don't actually see. Many times I have caught myself checking all the surfaces to see if they are moving when I wiggle the sticks only to realize I just went through the motions but really didn't notice if they were correct or not. Most recently was a reaction 54 turned it on, did all my normal checks of all surfaces and figured good to go. It was during start up I realized my left aileron was hanging down the servo had died. I could move it to center by hand and it would deflect upwards just fine but if i deflected it downwards that is where it stayed. I suppose it could have failed during my start up and had been ok when I did my control surface check but I feel like I missed it during the first check. This is an airplane that had flown many many times so I got complacent. Fortunately it was caught on the ground.