As a long time veteran of aviation maintenance; and a federally licensed airframe and power plant mechanic, I have worked on and flown in a ton of aircraft. On this subject I feel particularly qualified to comment. Other than acrobatic flight (and some bad weather) I can't think of anything that disturbed me more than test flying aircraft that had just come out of heavy maintenance. Almost all of the maneuvers that we put the jets through were done at high altitude, allowing ample time for recovery. The pilots of the Asiana flight in San Francisco did not have that luxury. Commercial jet liners and planes in general do not maneuver well at low altitudes and air speed. I won't go into the physics of it, but not having the altitude to recover is a major factor. Unless someone steps forward with an explanation or there was some sort of mechanical failure, those pilots flew that aircraft into the ground. When the A 300 was introduced Airbus decided to show it off at the Paris Air Show. One of the maneuvers was a slow fly by somewhat mimicking a missed approach and the pilots were supposed to go around and retry the landing. The video is eerily like the Asiana crash-too low, too high a sink rate, too little airspeed and no time to recover. They pancaked in as would have the Asiana flight except they got the nose up in time to slam the tail in first. Unfortunately getting the nose up killed airspeed and put the aircraft in a stall as the wings lost airflow and lift. What is disturbing and unfortunate is that every endeavor is capable of failure due to human error. Even in a modern airliner replete with every computer you can imagine to assist the pilots. When I worked at American we had an airplane crash in Colombia because the wrong city/airport codes were inputted in the computer by the pilots. There were other factors (aren't there always?), but the pilots were found at fault. Unfortunately; whatever the cause, it does not make the loss of life and trauma any easier to accept. We all can learn a lesson from accidents like this by being a little more diligent when making decisions.