The subject of the Air France flight 447 accident a few years ago continues to fascinate me for a variety of reasons. They are primarily because I am private pilot combined with a strong interest in technology. AF447 crashed in 2009 due to entering poor weather conditions at high altitude and the pilots reacting incorrectly to the conditions and losing control of the aircraft. In that situation something happened that deviated from the routine and the result was a catastrophe. I had an odd personal analogy to that today with something as simple as a bike ride. I have had my bike on a trainer in the basement for a number of months and took it out for a ride today. I usually have it in my garage and getting it requires me to walk past my helmet and gloves which causes me to pick them up and put them on. In taking the bike out of my basement I went out of a basement door and not through the garage. I started the ride and in about 15 minutes thought that something was different than usual. I quickly realized that the difference was the I was not wearing my helmet and gloves. It has been at least 20 years since I last rode a bike not wearing a helmet and I was shocked that I did that today. The causes were the usual things that lead to a problem while flying and were being in a hurry (I needed to get the ride in around lunch time) and doing something different than usual (the basement exit). If before starting the ride I sat and evaluated if everything was ready to go I'm positive that I would have noticed the lack of my helmet. In flying, I try to always do one last mental check before starting the engine to decide everything (including me) is ready and able to fly. Being in a hurry is one of the worse things that a pilot can do because it can cause checklist step results to be misinterpreted or missed entirely resulting in a problem sooner or later. Airbus Captain Bill Palmer is in the process of writing a book recounting the events of the AF447 accident and performing an analysis of the causes and recommendations for preventing it from happening again. Capt Palmer has a website on the book at http://understandingaf447.com/ and I recommend looking at it if you are interested in the subject.